ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Member of the Applications Low voltage, high density systems with Intermediate Bus Architectures (IBA) Point-of-load regulators for high performance DSP, FPGA, ASIC, and microprocessor applications Desktops, servers, and portable computing Broadband, networking, optical, and communications systems Active memory bus terminators Benefits Integrates digital power conversion with intelligent power management Eliminates the need for external power management components Completely programmable via industry-standard I2C communication bus One part that covers all applications Reduces board space, system cost and complexity, and time to market Family Features RoHS lead free and lead-solder-exempt products are available Wide input voltage range: 3V-13.2V High continuous output current: 20A Wide programmable output voltage range: 0.5V-5.5V Active digital current share Single-wire serial communication bus for frequency synchronization, programming, and monitoring Optimal voltage positioning with programmable slope of the VI line Overcurrent, overvoltage, undervoltage, and overtemperature protections with programmable thresholds and types Programmable fixed switching frequency 0.5-1.0MHz Programmable turn-on and turn-off delays Programmable turn-on and turn-off voltage slew rates with tracking protection Programmable feedback loop compensation Power Good signal with programmable limits Programmable fault management Start up into the load pre-biased up to 100% Full rated current sink Real time voltage, current, and temperature measurements, monitoring, and reporting Small footprint SMT package: 8x32mm Low profile of 14mm Compatible with conventional pick-and-place equipment Wide operating temperature range UL60950 recognized, CSA C22.2 No. 60950-00 certified, and TUV EN60950-1:2001 certified Description Power-One's point-of-load converters are recommended for use with regulated bus converters in an Intermediate Bus Architecture (IBA). The ZY7120 is an intelligent, fully programmable step-down point-of-load DC-DC module integrating digital power conversion and intelligent power management. When used with ZM7000 Series Digital Power Managers, the ZY7120 completely eliminates the need for external components for sequencing, tracking, protection, monitoring, and reporting. All parameters of the ZY7120 are programmable via the industry-standard I2C communication bus and can be changed by a user at any time during product development and service. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 1 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Reference Documents: ZM7XXX Digital Power Manager. Data Sheet ZM7XXX Digital Power Manager. Programming Manual Z-One(R) Graphical User Interface ZM00056-KIT USB to I2C Adapter Kit. User Manual 1. Ordering Information ZY 71 Product family: Z-One Module Series: Intelligent POL Converter 20 x y Output voltage setpoint accuracy: L - 1.2% or 20mV, whichever is greater. H1 - 1.0% or 10mV, whichever is greater Output Current: 20A - RoHS compliance: No suffix - RoHS compliant with Pb 2 solder exemption G - RoHS compliant for all six substances zz Packaging Option3: T1 - 500pcs T&R T2 - 100pcs T&R T3 - 50pcs T&R Q1 - 1pc sample for evaluation only Dash ______________________________________ 1 Contact factory for availability. The solder exemption refers to all the restricted materials except lead in solder. These materials are Cadmium (Cd), Hexavalent chromium (Cr6+), Mercury (Hg), Polybrominated biphenyls (PBB), Polybrominated diphenylethers (PBDE), and Lead (Pb) used anywhere except in solder. 3 Packaging option is used only for ordering and not included in the part number printed on the POL converter label. 4 The evaluation board is available in only one configuration: ZM7300-KIT-HKS. 2 Example: ZY7120HG-T2: A 100-piece reel of RoHS compliant POL converters with the output voltage setpoint of 1.0% or 10mV, whichever is greater. Each POL converter is labeled ZY7120HG. 2. Absolute Maximum Ratings Stresses in excess of the absolute maximum ratings may cause performance degradation, adversely affect longterm reliability, and cause permanent damage to the converter. 3. Parameter Conditions/Description Min Max Units Operating Temperature Controller case temperature -40 105 C Input Voltage 250ms Transient 15 VDC Output Current (See Output Current Derating Curves) 20 ADC -20 Environmental and Mechanical Specifications Parameter Conditions/Description Min Nom Max Units C Ambient Temperature Range -40 85 Storage Temperature (Ts) -55 125 C 15 grams Weight MTBF Calculated Per Telcordia Technologies SR-332 Peak Reflow Temperature ZY7120 ZY7120G Lead Plating ZY7120 and ZY7120G Moisture Sensitivity Level ZY7120 ZY7120G ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com 6.14 MHrs 220 C 245 260 C 100% Matte Tin or 1.5m Ag over 1.5m Ni 2 3 Page 2 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 4. Electrical Specifications Specifications apply at the input voltage from 3V to 13.2V, output load from 0 to 20A, ambient temperature from 40C to 85C, 100F output capacitance, and default performance parameters settings unless otherwise noted. 4.1 Input Specifications Parameter Input voltage (VIN) 4.2 Conditions/Description At VIN<4.75V, VLDO pin needs to be connected to an external voltage source higher than 4.75V Min Nom 3 Max Units 13.2 VDC Input Current (at no load) VIN4.75V, VLDO pin connected to VIN 50 mADC Undervoltage Lockout (VLDO connected to VIN) Ramping Up Ramping Down 4.2 3.75 VDC VDC Undervoltage Lockout (VLDO connected to VAUX=5V) Ramping Up Ramping Down 3.0 2.5 VDC VDC External Low Voltage Supply Connect to VLDO pin when VIN<4.75V VLDO Input Current Current drawn from the external low voltage supply at VLDO=5V 4.75 13.2 50 VDC mADC Output Specifications Parameter Conditions/Description 1 Min Nom Max Units 5.5 VDC VDC Programmable Default (no programming) VIN=12V, IOUT=0.5*IOUT MAX, FSW=500kHz, room temperature 0.5 Output Current (IOUT) VIN MIN to VIN MAX -202 Line Regulation VIN MIN to VIN MAX 0.3 %VOUT Load Regulation 0 to IOUT MAX 0.2 %VOUT Dynamic Regulation Peak Deviation Settling Time Slew rate 1A/s, 50 -100% load step COUT=330F, FSW=1MHz to 10% of peak deviation 75 50 mV s Output Voltage Peak-to-Peak Ripple and Noise BW=20MHz Full Load VIN=5.0V, VOUT=0.5V VIN=5.0V, VOUT=2.5V VIN=13.2V, VOUT=0.5V VIN=13.2V, VOUT=2.5V VIN=13.2V, VOUT=5.0V 10 20 15 35 50 mV mV mV mV mV Temperature Coefficient VIN=12V, IOUT=0.5*IOUT MAX 20 ppm/C Default Programmable, 250kHz steps Default Programmable, 1.56% steps 500 Output Voltage Range (VOUT) Output Voltage Setpoint Accuracy Switching Frequency Duty Cycle Limit 0.5 (See Ordering Information) 20 500 1,000 90.5 0 95 1 ADC kHz kHz % % ZY7120 is a step-down converter, thus the output voltage is always lower than the input voltage as show in Figure 1. At the negative output current (bus terminator mode) efficiency of the ZY7120 degrades resulting in increased internal power dissipation. Therefore maximum allowable negative current under specific conditions is 20% lower than the current determined from the derating curves shown in paragraph 5.5. 2 ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 3 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Figure 1. Output Voltage as a Function of Input Voltage and Output Current 4.3 Protection Specifications Parameter Conditions/Description Min Nom Max Units Output Overcurrent Protection Type Threshold Default Programmable Default Programmable in 11 steps Threshold Accuracy 50 Non-Latching, 130ms period Latching/Non-Latching 140 %IOUT 140 %IOUT -25 25 %IOCP.SET Output Overvoltage Protection Default Programmable Default Programmable in 10% steps 1101 Threshold Accuracy Measured at VO.SET=2.5V -2 Delay From instant when threshold is exceeded until the turn-off command is generated Type Threshold ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Non-Latching, 130ms period Latching/Non-Latching 130 %VO.SET 130 %VO.SET 2 %VOVP.SET 6 s Page 4 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Output Undervoltage Protection Default Programmable Default Programmable in 5% steps 75 Non-Latching, 130ms period Latching/Non-Latching 75 %VO.SET 85 %VO.SET Threshold Accuracy Measured at VO.SET=2.5V -2 2 Delay From instant when threshold is exceeded until the turn-off command is generated Type Threshold %VUVP.SET 6 s Overtemperature Protection Type Default Programmable Turn Off Threshold Temperature is increasing 130 C Turn On Threshold Temperature is decreasing after the module was shut down by OTP 120 C Threshold Accuracy Delay Non-Latching, 130ms period Latching/Non-Latching -5 From instant when threshold is exceeded until the turn-off command is generated 5 6 C s Tracking Protection (when Enabled) Type Default Programmable Threshold Enabled during output voltage ramping up Threshold Accuracy Delay Disabled Latching/Non-Latching, 130ms period -50 From instant when threshold is exceeded until the turn-off command is generated 250 mVDC 50 mVDC 6 s 120 C Overtemperature Warning Threshold Always enabled, reported in Status register Threshold Accuracy -5 Hysteresis Delay From instant when threshold is exceeded until the warning signal is generated 5 C 3 C 6 s Power Good Signal (PGOOD pin) Logic Lower Threshold VOUT is inside the PG window VOUT is outside the PG window Default Programmable in 5% steps High Low 90 90 Upper Threshold Delay From instant when threshold is exceeded until status of PG signal changes Threshold Accuracy Measured at VO.SET=2.5V -2 N/A 95 110 %VO.SET 6 s 2 ___________________ 1 Minimum OVP threshold is 1.0V ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com %VO.SET %VO.SET Page 5 of 34 %VO.SET ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 4.4 Feature Specifications Parameter Conditions/Description Min Nom Max Units Current Share Type Maximum Number of Modules Connected in Parallel Maximum Number of Modules Connected in Parallel Active, Single Line IOUT MIN20%*IOUT NOM 10 IOUT MIN=0 4 Current Share Accuracy IOUT MIN20%*IOUT NOM Interleave (Phase Shift) Default Programmable in 11.25 steps 20 %IOUT 348.75 Degree degree Interleave 0 0 Sequencing Turn ON Delay Turn OFF Delay Default Programmable in 1ms steps Default Programmable in 1ms steps 0 0 255 0 0 63 ms ms ms ms Tracking Turn ON Slew Rate Turn OFF Slew Rate Default Programmable in 7 steps Default Programmable in 7 steps 0.1 -8.331 V/ms V/ms V/ms V/ms 0 6.02 mV/A mV/A Programmable 0.05 50 kHz Programmable 0.05 50 kHz Programmable 0.05 50 kHz Programmable 1 1000 kHz Programmable 1 1000 kHz 0.1 -0.1 -0.1 8.331 Optimal Voltage Positioning Load Regulation Default Programmable in 7 steps 0 Feedback Loop Compensation Zero1 (Effects phase lead and increases gain in mid-band) Zero 2 (Effects phase lead and increases gain in mid-band) Pole 1 (Integrator Pole, effects loop gain) Pole 2 (Effects phase lag and limits gain in mid-band) Pole 3 (High frequency low- pass filter to limit PWM noise) Monitoring Voltage Monitoring Accuracy 1 LSB=22mV -2%VOUT - 1 LSB 2%VOUT + 1 LSB mV Current Monitoring Accuracy 20%*IOUT NOM < IOUT < IOUT NOM -20 +20 %IOUT Temperature Monitoring Accuracy Junction temperature of POL controller -5 +5 C Remote Voltage Sense (+VS and -VS pins) Voltage Drop Compensation Between +VS and VOUT 300 mV Voltage Drop Compensation Between -VS and PGND 100 mV ___________________ 1 Achieving fast slew rates under specific line and load conditions may require feedback loop adjustment ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 6 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 4.5 Signal Specifications Parameter Conditions/Description Min Nom Max Units VDD Internal supply voltage 3.15 3.3 3.45 V 0.3 x VDD V VDD + 0.5 V 0.45 x VDD V 60 mA 300 ns 10 pF mA SYNC/DATA Line (SD pin) ViL_sd LOW level input voltage -0.5 ViH_sd HIGH level input voltage Vhyst_sd Hysteresis of input Schmitt trigger VoL LOW level sink current @ 0.5V Tr_sd Maximum allowed rise time 10/90%VDD Cnode_sd Added node capacitance Ipu_sd Pull-up current source at Vsd=0V 0.3 1.0 Freq_sd Clock frequency of external SD line 475 525 0.75 x VDD 0.25 x VDD 14 5 Tsynq Sync pulse duration 22 28 T0 Data=0 pulse duration 72 78 kHz % of clock cycle % of clock cycle Inputs: ADDR0...ADDR4, EN, IM ViL_x LOW level input voltage -0.5 0.3 x VDD V ViH_x HIGH level input voltage 0.7 x VDD VDD+0.5 V Vhyst_x Hysteresis of input Schmitt trigger 0.1 x VDD 0.3 x VDD V RdnL_ADDR External pull down resistance ADDRX forced low 10 kOhm Power Good and OK Inputs/Outputs Iup_PG Pull-up current source input forced low PG 25 110 A Iup_OK Pull-up current source input forced low OK 175 725 A ViL_x LOW level input voltage -0.5 0.3 x VDD V ViH_x HIGH level input voltage 0.7 x VDD VDD+0.5 V Vhyst_x Hysteresis of input Schmitt trigger 0.1 x VDD 0.3 x VDD V IoL LOW level sink current at 0.5V 4 20 mA Current Share Bus (CS pin) Iup_CS Pull-up current source at VCS = 0V 0.84 3.1 mA ViL_CS LOW level input voltage -0.5 0.3 x VDD V ViH_CS HIGH level input voltage VDD+0.5 V Vhyst_CS Hysteresis of input Schmitt trigger 0.45 x VDD V IoL LOW level sink current at 0.5V 60 mA Tr_CS Maximum allowed rise time 10/90% VDD 100 ns ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com 0.75 x VDD 0.25 x VDD 14 Page 7 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 5. Typical Performance Characteristics 5.1 94 Efficiency Curves 92 96 90 88 92 86 90 84 Efficiency, % 94 Efficiency, % 88 86 84 82 80 78 76 82 74 80 72 78 70 76 68 74 Vout=0.5V Vout=1.2V Vout=2.5V 0 2 4 6 Vout=1.2V Vout=2.5V Vout=3.3V Vout=5.0V 8 10 12 14 16 18 20 Output Current, A 72 0 2 4 6 8 10 12 14 16 18 20 Output Current, A Figure 4. Efficiency vs. Load. Vin=12V, Fsw=500kHz Figure 2. Efficiency vs. Load. Vin=3.3V, Fsw=500kHz 95 96 90 94 85 92 Efficiency, % 90 Efficiency, % 88 86 84 82 80 75 70 80 78 65 76 Vin=3.3V 74 72 70 0 2 4 Vout=0.5V Vout=1.2V Vout=2.5V Vout=3.3V 6 8 10 12 Output Current, A 14 16 Vin=5.0V Vin=12V 60 0.5 1.5 2.5 3.5 4.5 Output Voltage, V 18 20 Figure 5. Efficiency vs. Output Voltage, Iout=20A, Fsw=500kHz Figure 3. Efficiency vs. Load. Vin=5V, Fsw=500kHz ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 8 of 34 5.5 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 95 90 89 90 88 87 85 Efficiency, % Efficiency, % 86 80 75 85 84 83 82 70 81 80 65 Vout=0.5V Vout=1.2V Fsw=500kHz 79 Vout=2.5V 60 Fsw=750kHz Fsw=1,000kHz 78 3 4 5 6 7 8 9 10 11 12 0 2 4 6 8 10 12 14 16 18 20 Output Current, A Input Voltage, V Figure 8. Efficiency vs. Load. Vin=5V, Vout=1.2V Figure 6. Efficiency vs. Input Voltage. Iout=20A, Fsw=500kHz 96 94 93 95 92 91 94 Efficiency, % Efficiency, % 90 93 92 89 88 87 86 91 85 84 90 Fsw=500kHz Fsw=750kHz 83 Fsw=1,000kHz 89 Fsw=500kHz Fsw=750kHz Fsw=1,000kHz 82 0 2 4 6 8 10 12 14 16 18 20 Output Current, A 2 4 6 8 10 12 14 16 18 Output Current, A Figure 7. Efficiency vs. Load. Vin=3.3V, Vout=2.5V ZD-00194 Rev. 2.5, 01-Jul-10 0 www.power-one.com Figure 9. Efficiency vs. Load. Vin=12V, Vout=5V Page 9 of 34 20 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 94 93 92 91 Efficiency, % 90 89 Vin=3.3V, Vout=2.5V 88 Vin=5V, Vout=1.2V 87 Vin=12V, Vout=5V 86 85 84 83 82 500 750 1000 Switching Frequency, kHz Figure 10. Efficiency vs. Switching Frequency. Iout=20A 5.2 Figure 12. Turn-On with Different Rising Slew Rates. Rising Slew Rates are Programmed as follows: V11V/ms, V2-0.5V/ms, V3-0.2V/ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 Turn-On Characteristics Figure 11. Tracking Turn-On. Rising Slew Rate is Programmed at 0.5V/ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Figure 13. Sequenced Turn-On. Rising Slew Rate is Programmed at 1V/ms. V2 Delay is 2ms, V3 delay is 4ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 Page 10 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 5.3 Figure 14. Turn On with Sequencing and Tracking. Rising Slew Rate Programmed at 0.2V/ms, V1 and V3 delays are programmed at 20ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 Figure 15. Turn On into Prebiased Load. V3 is Prebiased by V2 via a Diode. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Turn-Off Characteristics Figure 16. Tracking Turn-Off. Falling Slew Rate is Programmed at 0.5V/ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 Figure 17. Turn-Off with Tracking and Sequencing. Falling Slew Rate is Programmed at 0.5V/ms. Vin=12V, Ch1 - V1, Ch2 - V2, Ch3 - V3 Page 11 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 5.4 Transient Response The pictures below show the deviation of the output voltage in response to the 50-100-50% step load at 1A/s. In all tests the ZY7120 converters were switching at 1MHz and had 5x22F and 5x47F ceramic capacitors connected across the output pins. Bandwidth of the feedback loop was programmed for faster transient response. Figure 20. Vin=5V, Vout=2.5V, BW~45kHz Figure 18. Vin=12V, Vout=5V, BW~40kHz Figure 21. Vin=5V, Vout=1V, BW~40kHz Figure 19. Vin=12V, Vout=1V, BW~35kHz Figure 22. Vin=3.3V, Vout=1V, BW~40kHz ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 12 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 5.5 Thermal Derating Curves 20 Output Current, A 18 16 14 12 10 0 LFM 100 LFM 200 LFM 400 LFM 600 LFM 8 35 45 55 65 75 85 Temperature, 'C Figure 23. Thermal Derating Curves. Vin=13.2V, Vout=5.0V, Fsw=500kHz Output Current, A 20 19 18 17 16 0 LFM 100 LFM 200 LFM 400 LFM 600 LFM 15 65 70 75 Temperature, 'C 80 85 Figure 24. Thermal Derating Curves. Vin=5.0V, Vout=2.5V, Fsw=500kHz ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 13 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 6. Typical Application Intermediate Voltage Bus 2 IC DPM SD OK_C OK_B OK_A CS ZY7120 ZY7120 ADDR ADDR V1 ZY7120 ADDR ADDR ZY7120 V2 V3 2 Figure 25. Block Diagram of Typical Multiple Output Application with Digital Power Manager and I C Interface The block diagram of a typical application of ZY7120 point-of-load converters (POL) is shown in Figure 25. The system includes multiple POLs and a ZM7000 series Digital Power Manager (DPM). All POLs are connected to the DPM and to each other via a single-wire SD (sync/data) line. The line provides synchronization of all POLs to the master clock generated by the DPM and simultaneously performs bidirectional data transfer between POLs and the DPM. Each POL has a unique 5-bit address programmed by grounding respective address pins. To enable the current share, CS pins of POLs connected in parallel are linked together. There are three groups of POLs in the application, groups A, B, and group C. A group is defined as a number of POLs interconnected via OK pins. Grouping of POLs enables users to program, control, and monitor multiple POLs simultaneously and execute advanced fault management schemes. The complete schematic of the application is shown in Figure 26. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 14 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Figure 26. Complete Schematic of the Application Shown in Figure 25. Intermediate Bus Voltage is from 4.75V to 13.2V. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 15 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 7. Pin Assignments and Description Pin Name Pin Number Pin Type VLDO 1 P IM Buffer Type Pin Description Notes Low Voltage Dropout Connect to an external voltage source higher than 4.75V, if VIN<4.75V. Connect to VIN, if VIN4.75V 2 Not Used Leave floating NC 3 Not Used Leave floating NC 4 Not Used Leave floating NC 5 Not Used Leave floating NC 6 Not Used Leave floating NC 7 Not Used Leave floating NC 8 Not Used Leave floating VREF 9 Not Used Leave floating EN 10 Connect to PGND Connect to PGND OK 11 I/O PU Fault/Status Condition Connect to OK pin of other Z-POL and/or DPM. Leave floating, if not used SD 12 I/O PU Sync/Data Line Connect to SD pin of DPM PGOOD 13 I/O PU Power Good TRIM 14 Not Used Leave floating CS 15 I/O PU Current Share Connect to CS pin of other Z-POLs connected in parallel ADDR4 16 I PU POL Address Bit 4 Tie to PGND for 0 or leave floating for 1 ADDR3 17 I PU POL Address Bit 3 Tie to PGND for 0 or leave floating for 1 ADDR2 18 I PU POL Address Bit 2 Tie to PGND for 0 or leave floating for 1 ADDR1 19 I PU POL Address Bit 1 Tie to PGND for 0 or leave floating for 1 ADDR0 20 I PU POL Address Bit 0 Tie to PGND for 0 or leave floating for 1 -VS 21 I PU Negative Voltage Sense Connect to the negative point close to the load +VS 22 I PU Positive Voltage Sense Connect to the positive point close to the load VOUT 23 P Output Voltage PGND 24 P Power Ground VIN 25 P Input Voltage Legend: I=input, O=output, I/O=input/output, P=power, A=analog, PU=internal pull-up ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 16 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8. Programmable Features Performance parameters of ZY7120 POL converters can be programmed via the industry standard I2C communication bus without replacing any components or rewiring PCB traces. Each parameter has a default value stored in the volatile memory registers detailed in Table 1. The setup registers 00h through 14h are programmed at the system power-up. When the user programs new performance parameters, the values in the registers are overwritten. Upon removal of the input voltage, the default values are restored. Table 1. ZY7120 Memory Registers Register PC1 PC2 PC3 DON DOF TC INT RUN ST VOS CLS DCL B1 B2 B3 C0L C0H C1L C1H C2L C2H C3L C3H VOM IOM TMP Content Protection Configuration 1 Protection Configuration 2 Protection Configuration 3 Turn-On Delay Turn-Off Delay Tracking Configuration Interleave Configuration and Frequency Selection RUN Register Status Register Output Voltage Setpoint Current Limit Setpoint Duty Cycle Limit Dig Controller Denominator z-1 Coefficient Dig Controller Denominator z-2 Coefficient Dig Controller Denominator z-3 Coefficient Dig Controller Numerator z0 Coefficient, Low Byte Dig Controller Numerator z0 Coefficient, High Byte Dig Controller Numerator z-1 Coefficient, Low Byte Dig Controller Numerator z-1 Coefficient, High Byte Dig Controller Numerator z-2 Coefficient, Low Byte Dig Controller Numerator z-2 Coefficient, High Byte Dig Controller Numerator z-3 Coefficient, High Byte Dig Controller Numerator z-3 Coefficient, Low Byte Output Voltage Monitoring Output Current Monitoring Temperature Monitoring Address 00h 01h 02h 05h 06h 03h 04h ZY7120 converters can be programmed using the Graphical User Interface or directly via the I2C bus by using high and low level commands as described in the `"DPM Programming Manual". ZY7120 parameters can be reprogrammed at any time during the system operation and service except for the digital filter coefficients, the switching frequency and the duty cycle limit, that can only be changed when the POL is turned off. 8.1 Output Voltage The output voltage can be programmed in the GUI Output Configuration window shown in the Figure 27 or directly via the I2C bus by writing into the VOS register shown in Figure 28. 15h 16h 07h 08h 09h 0Ah 0Bh 0Ch 0Dh 0Eh Figure 27. Output Configuration Window 0Fh 10h 11h 12h 13h 14h 17h 18h 19h R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 VOS7 VOS6 VOS5 VOS4 VOS3 VOS2 VOS1 VOS0 Bit 7 Bit 7:0 VOS[7:0], Output voltage setting 00h: corresponds to 0.5000V 01h: corresponds to 0.5125V ... 77h: corresponds to 1.9875V 78h: corresponds to 2.0000V 79h: corresponds to 2.025V ... F9h: corresponds to 5.225V FAh: corresponds to 5.250V FBh: corresponds to 5.300V ... FFh: corresponds to 5.500V Bit 0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Figure 28. Output Voltage Setpoint Register VOS ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 17 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8.1.1 Output Voltage Setpoint The output voltage programming range is from 0.5V to 5.5V. Within this range, there are 256 predefined voltage setpoints. To improve resolution of the output voltage settings, the voltage range is divided into three sub-ranges as shown in Table 2. Table 2. Output Voltage Adjustment Resolution VOUT MIN, V VOUT MAX, V Resolution, mV 0.500 2.000 12.5 2.025 5.25 25 5.3 5.5 50 8.1.2 Output Voltage Margining If the output voltage needs to be varied by a certain percentage, the margining function can be utilized. The margining can be programmed in the GUI Output Configuration window or directly via the I2C bus using high level commands as described in the `"DPM Programming Manual". In order to properly margin POLs that are connected in parallel, the POLs must be members of one of the Parallel Buses. Refer to the GUI System Configuration Window shown in Figure 55. 8.1.3 Optimal Voltage Positioning Optimal voltage positioning increases the voltage regulation window by properly positioning the output voltage setpoint. Positioning is determined by the load regulation that can be programmed in the GUI Output Configuration window shown in Figure 27 or directly via the I2C bus by writing into the CLS register shown in Figure 38. Figure 29 illustrates optimal voltage positioning concept. If no load regulation is programmed, the headroom (voltage differential between the output voltage setpoint and a regulation limit) is approximately half of the voltage regulation window. When load regulation is programmed, the output voltage will decrease as the output current increases, so the VI characteristic will have a negative slope. Therefore, by properly selecting the operating point, it is possible to increase the headroom as shown in the picture. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com VOUT Upper Regulation Limit Lower Regulation Limit Operating Point VI Curve Without Load Regulation VI Curve With Load Regulation Headroom without Load Regulation Headroom with Load Regulation Light Load IOUT Heavy Load Figure 29. Concept of Optimal Voltage Positioning Increased headroom allows tolerating larger voltage deviations. For example, the step load change from light to heavy load will cause the output voltage to drop. If the optimal voltage positioning is utilized, the output voltage will stay within the regulation window. Otherwise, the output voltage will drop below the lower regulation limit. To compensate for the voltage drop external output capacitance will need to be added, thus increasing cost and complexity of the system. The effect of optimal voltage positioning is shown in Figure 30 and Figure 31. In this case, switching output load causes large peak-to-peak deviation of the output voltage. By programming load regulation, the peak to peak deviation is dramatically reduced. Figure 30. Transient Response without Optimal Voltage Positioning Page 18 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 DON7 DON6 DON5 DON4 DON3 DON2 DON1 DON0 Bit 7 Bit 0 Bit 7:0 DON[7:0]: Turn-on delay time 00h: corresponds to 0ms delay after turn-on command has occurred ... FFh: corresponds to 255ms delay after turn-on command has occurred Figure 33. Turn-On Delay Register DON 8.2.2 Turn-Off Delay U U R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 --- --- DOF5 DOF4 DOF3 DOF2 DOF1 DOF0 Bit 7 Bit 0 Bit 7:6 Unimplemented, read as `0' Figure 31. Transient Response with Optimal Voltage Positioning 8.2 Bit 5:0 DOF[5:0]: Turn-off delay time 00h: corresponds to 0ms delay after turn-off command has occurred ... 3Fh: corresponds to 63ms delay after turn-off command has occurred Figure 34. Turn-Off Delay Register DOF Sequencing and Tracking Turn-on delay, turn-off delay, and rising and falling output voltage slew rates can be programmed in the GUI Sequencing/Tracking window shown in Figure 32 or directly via the I2C bus by writing into the DON, DOF, and TC registers, respectively. The registers are shown in Figure 33, Figure 34, and Figure 36. Turn-off delay is defined as an interval from the application of the Turn-Off command until the output voltage reaches zero (if the falling slew rate is programmed) or until both high side and low side switches are turned off (if the slew rate is not programmed). Therefore, for the slew rate controlled turn-off the ramp-down time is included in the turn-off delay as shown in Figure 35. User programmed turn-off delay, TDF Turn-Off Command Internal ramp-down command VOUT Calculated delay TD Ramp-down time, TF Falling slew rate dVF/dT Figure 32. Sequencing/Tracking Window 8.2.1 Turn-On Delay Turn-on delay is defined as an interval from the application of the Turn-On command until the output voltage starts ramping up. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Time Figure 35. Relationship between Turn-Off Delay and Falling Slew Rate As it can be seen from the figure, the internally calculated delay TD is determined by the equation below. V TD TDF OUT , dVF dT For proper operation TD shall be greater than zero. The appropriate value of the turn-off delay needs to be programmed to satisfy the condition. Page 19 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output If the falling slew rate control is not utilized, the turnoff delay only determines an interval from the application of the Turn-Off command until both high side and low side switches are turned off. In this case, the output voltage ramp-down process is determined by load parameters. 8.2.3 Rising and Falling Slew Rates The output voltage tracking is accomplished by programming the rising and falling slew rates of the output voltage. To achieve programmed slew rates, the output voltage is being changed in 12.5mV steps where duration of each step determines the slew rate. For example, ramping up a 1.0V output with a slew rate of 0.5V/ms will require 80 steps duration of 25s each. Duration of each voltage step is calculated by dividing the master clock frequency generated by the DPM. Since all POLs in the system are synchronized to the master clock, the matching of voltage slew rates of different outputs is very accurate as it can be seen in Figure 11 and Figure 16. During the turn on process, a POL not only delivers current required by the load (ILOAD), but also charges the load capacitance. The charging current can be determined from the equation below: ICHG CLOAD dVR R/W-0 R/W-0 R/W-0 R/W-1 R/W-0 R/W-0 --- R2 R1 R0 SC F2 F1 Bit 7 Bit 7 Unimplemented , read as `0' When selecting the rising slew rate, a user needs to ensure that I LOAD ICHG IOCP Where IOCP is the overcurrent protection threshold of the ZY7120. If the condition is not met, then the overcurrent protection will be triggered during the turn-on process. To avoid this, dVR/dt and the overcurrent protection threshold should be programmed to meet the condition above. www.power-one.com F0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Bit 6:4 R[2:0]: Value of Vo rising slope 0: corresponds to 0.1V/ms (default) 1: corresponds to 0.2V/ms 2: corresponds to 0.5V/ms 3: corresponds to 1.0V/ms 4: corresponds to 2.0V/ms 5: corresponds to 5.0V/ms 6: corresponds to 8.3V/ms 7: corresponds to 8.3V/ms Bit 3 R/W-0 Bit 0 SC, Slew rate control at turn-off 0: Slew rate control is disabled 1: Slew rate control is enabled Bit 2:0 F[2:0]: Value of Vo falling slope 0: corresponds to -0.1V/ms (default) 1: corresponds to -0.2V/ms 2: corresponds to -0.5V/ms 3: corresponds to -1.0V/ms 4: corresponds to -2.0V/ms 5: corresponds to -5.0V/ms 6: corresponds to -8.3V/ms 7: corresponds to -8.3V/ms Figure 36. Tracking Configuration Register TC 8.3 Protections ZY7120 Series converters have a comprehensive set of programmable protections. The set includes the output over- and undervoltage protections, overcurrent protection, overtemperature protection, tracking protection, overtemperature warning, and Power Good signal. Status of protections is stored in the ST register shown in Figure 37. dt Where, CLOAD is load capacitance, dVR/dt is rising voltage slew rate, and ICHG is charging current. ZD-00194 Rev. 2.5, 01-Jul-10 U R-1 R-0 R-1 R-1 R-1 R-1 R-1 TP PG TR OT OC UV OV Bit 7 R-1 PV Bit 0 Bit 7 TP: Temperature Warning Bit 6 PG: Power Good Warning Bit 5 TR: Tracking Fault Bit 4 OT: Overtemperature Fault Bit 3 OC: Overcurrent Fault Bit 2 UV: Undervoltage Fault Bit 1 OV: Overvoltage Error Bit 0 PV: Phase Voltage Error R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Note: - An activated warning/fault/error is encoded as `0' Figure 37. Protection Status Register ST Thresholds of overcurrent, over- and undervoltage protections, and Power Good limits can be programmed in the GUI Output Configuration window or directly via the I2C bus by writing into the CLS and PC2 registers shown in Figure 38 and Figure 39. Page 20 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output R/W-0 R/W-0 R/W-0 R/W-1 R/W-1 R/W-0 R/W-1 R/W-1 LR2 LR1 LR0 TCE CLS3 CLS2 CLS1 CLS0 Bit 7 Bit 0 Bit 7:5 LR[2:0], Load regulation configuration 000: 0 V/A/Ohm 001: 0.39 V/A/Ohm 010: 0.78 V/A/Ohm 011: 1.18 V/A/Ohm 100: 1.57 V/A/Ohm 101: 1.96 V/A/Ohm 110: 2.35 V/A/Ohm 111: 2.75 V/A/Ohm Bit 4 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset TCE, Temperature compensation enable 0: disabled 1: enabled Bit 3:0 CLS[3:0], Current limit setting 0h: corresponds to 37% 1h: corresponds to 47% ... Bh: corresponds to 140% Values higher than Bh are translated to Bh (140%) Figure 40. Fault Management Window Figure 38. Current Limit Setpoint Register CLS U U U R/W-0 R/W-1 R/W-0 R/W-0 R/W-0 --- --- --- PGLL OVPL1 OVPL0 UVPL1 UVPL0 Bit 7 Bit 7:5 Unimplemented, read as `0' PGLL: Set Power Good Low Level Bit 4 1 = 95% of Vo 0 = 90% of Vo (Default) Bit 3:2 OVPL[1:0]: Set Over Voltage Protection Level 00 = 110% of Vo 01 = 120% of Vo 10 = 130% of Vo (Default) 11 = 130% of Vo R/W-0 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-1 TRE PVE TRP OTP OCP UVP OVP Bit 7 Bit 1:0 UVPL[1:0]: Set Under Voltage Protection Level 00 = 75% of Vo (Default) 01 = 80% of Vo 10 = 85% of Vo TRE: Tracking fault enable 1 = enabled 0 = disabled Bit 6 PVE: Phase voltage error enable 1 = enabled 0 = disabled Bit 5 TRP: Tracking fault protection 1 = latching 0 = non latching Bit 4 OTP: Overtemperature protection configuration 1 = latching 0 = non latching Bit 3 OCP: Overcurrent protection configuration 1 = latching 0 = non latching Bit 2 UVP: Undervoltage protection configuration 1 = latching 0 = non latching Bit 1 OVP: Overvoltage protection configuration 1 = latching 0 = non latching Bit 0 PVP: Phase Voltage Protection 1 = latching 0 = non latching Figure 39. Protection Configuration Register PC2 Note that the overvoltage and undervoltage protection thresholds and Power Good limits are defined as percentages of the output voltage. Therefore, the absolute levels of the thresholds change when the output voltage setpoint is changed either by output voltage adjustment or by margining. In addition, a user can change type of protections (latching or non-latching) or disable certain protections. These settings are programmed in the GUI Fault Management window shown in Figure 40 or directly via the I2C by writing into the PC1 register shown in Figure 41. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com PVP Bit 0 Bit 7 Bit 0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset R/W-1 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Figure 41. Protection Configuration Register PC1 If the non-latching protection is selected, a POL will attempt to restart every 130ms until the condition that triggered the protection is removed. When restarting, the output voltages follow tracking and sequencing settings. If the latching type is selected, a POL will turn off and stay off. The POL can be turned on after 130ms, if the condition that caused the fault is removed and the respective bit in the ST register was cleared, or the Turn On command was recycled, or the input voltage was recycled. Page 21 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output All protections can be classified into three groups based on their effect on system operation: warnings, faults, and errors. 8.3.1 Warnings This group includes Overtemperature Warning and Power Good Signal. The warnings do not turn off POLs but rather generate signals that can be transmitted to a host controller via the I2C bus. 8.3.1.1 Overtemperature Warning The Overtemperature Warning is generated when temperature of the controller exceeds 120C. The Overtemperature Warning changes the PT bit of the status register ST to 0 and sends the signal to the DPM. Reporting is enabled in the GUI Fault Management window or directly via the I2C by writing into the PC3 register shown in Figure 43. When the temperature falls below 117C, the PT bit is cleared and the Overtemperature Warning is removed. 8.3.1.2 Power Good Power Good is an open collector output that is pulled low, if the output voltage is outside of the Power Good window. The window is formed by the Power Good High threshold that is equal to 110% of the output voltage and the Power Good Low threshold that can be programmed at 90 or 95% of the output voltage. The Power Good protection is only enabled after the output voltage reaches its steady state level. The PGOOD pin is pulled low during transitions of the output voltage from one level to other as shown in Figure 42. The Power Good Warning pulls the Power Good pin low and changes the PG bit of the status register ST to 0. It sends the signal to the DPM, if the reporting is enabled. When the output voltage returns within the Power Good window, the PG pin is pulled high, the PG bit is cleared and the Power Good Warning is removed. The Power Good pin can also be pulled low by an external circuit to initiate the Power Good Warning. Note: To retrieve status information, Status Monitoring in the GUI POL Group Configuration Window should be enabled (refer to Digital Power Manager Data Sheet). The DPM will retrieve the status information from each POL on a continuous basis. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com 8.3.2 Faults This group includes overcurrent, overtemperature, undervoltage, and tracking protections. Triggering any protection in this group will turn off the POL. 8.3.2.1 Overcurrent Protection Overcurrent protection is active whenever the output voltage of the POL exceeds the prebias voltage (if any). When the output current reaches the OC threshold, the output voltage will start decreasing. As soon as the output voltage decreases below the undervoltage protection threshold, the OC fault signal is generated, the POL turns off and the OC bit in the register ST is changed to 0. Both high side and low side switches of the POL are turned off instantly (fast turn-off). The temperature compensation is added to keep the OC threshold approximately constant at temperatures above room temperature. Note that the temperature compensation can be disabled in the GUI Output Configuration window or directly via the I2C by writing into the CLS register. However, it is recommended to keep the temperature compensation enabled. 8.3.2.2 Undervoltage Protection The undervoltage protection is only active during steady state operation of the POL to prevent nuisance tripping. If the output voltage decreases below the UV threshold and there is no OC fault, the UV fault signal is generated, the POL turns off, and the UV bit in the register ST is changed to 0. The output voltage is ramped down according to sequencing and tracking settings (regular turn-off). 8.3.2.3 Overtemperature Protection Overtemperature protection is active whenever the POL is powered up. If temperature of the controller exceeds 130C, the OT fault is generated, POL turns off, and the OT bit in the register ST is changed to 0. The output voltage is ramped down according to sequencing and tracking settings (regular turn-off). If non-latching OTP is programmed, the POL will restart as soon as the temperature of the controller decreases below the Overtemperature Warning threshold of 120C. Page 22 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8.3.2.4 Tracking Protection Tracking protection is active only when the output voltage is ramping up. The purpose of the protection is to ensure that the voltage differential between multiple rails being tracked does not exceed 250mV. This protection eliminates the need for external clamping diodes between different voltage rails which are frequently recommended by ASIC manufacturers. When the tracking protection is enabled, the POL continuously compares actual value of the output voltage to its programmed value as defined by the output voltage and its rising slew rate. If absolute value of the difference exceeds 250mV, the tracking fault signal is generated, the POL turns off, and the TR bit in the register ST is changed to 0. Both high side and low side switches of the POL are turned off instantly (fast turn-off). The tracking protection can be disabled, if it contradicts requirements of a particular system (for example turning into high capacitive load where rising slew rate is not important). It can be disabled in the GUI Fault Management window or directly via the I2C bus by writing into the PC1 register. Vo Enable command 1 0 OTP continuously enabled 1 0 OCP enabled Power Good Signal 1 0 OVP Threshold OVP Threshold PG High=110%VOUT PG High=110%VOUT OVP Threshold Output Voltage 1.0V prebiased output Output Voltage PG High=110%VOUT PG Low Threshold Output Voltage PG Low Threshold UVP Threshold PG Low Threshold UVP Threshold UVP Threshold Tracking Thresholds Time Figure 42. Protections Enable Conditions 8.3.3 Errors The group includes overvoltage protection and the phase voltage error. The phase voltage error is not available in ZY7120. 8.3.3.1 Overvoltage Protection The overvoltage protection is active whenever the output voltage of the POL exceeds the pre-bias voltage (if any). If the output voltage exceeds the overvoltage protection threshold, the overvoltage error signal is generated, the POL turns off, and the OV bit in the register ST is changed to 0. The high side switch is turned off instantly, and simultaneously the low side switch is turned on to ensure reliable protection of sensitive loads. The low side switch provides low impedance path to quickly dissipate ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com energy stored in the output filter and achieve effective voltage limitation. The OV threshold can be programmed from 110% to 130% of the output voltage setpoint, but not lower than 1.0V. 8.3.4 Faults and Errors Propagation The feature adds flexibility to the fault management scheme by giving users control over propagation of fault signals within and outside of the system. The propagation means that a fault in one POL can be programmed to turn off other POLs and devices in the system, even if they are not directly affected by the fault. Page 23 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8.3.4.1 Grouping of POLs Z-Series POLs can be arranged in several groups to simplify fault management. A group of POLs is defined as a number of POLs with interconnected OK pins. A group can include from 1 to 32 POLs. If fault propagation within a group is desired, the propagation bit needs to be checked in the GUI Fault Management Window. The parameters can also be programmed directly via the I2C bus by writing into the PC3 register shown in Figure 43. When propagation is enabled, the faulty POL pulls its OK pin low. A low OK line initiates turn-off of other POLs in the group. R/W-0 R/W-0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 PTM PGM TRP OTP OCP UVP OVP R/W-1 Bit 7 PVP Bit 0 Bit 7 PTM: Temperature warning Message 1 = enabled 0 = disabled Bit 6 PGM: Power good message 1 = enabled 0 = disabled Bit 5 TRP : Tracking fault propagation 1 = enabled 0 = disabled Bit 4 OTP: Overtemperature fault propagation 1 = enabled 0 = disabled Bit 3 OCP: Overcurrent fault propagation 1 = enabled 0 = disabled Bit 2 UVP: Undervoltage fault propagation 1 = enabled 0 = disabled Bit 1 OVP: Overvoltage error propagation 1 = enabled 0 = disabled Bit 0 PVP : Phase voltage error propagation 1 = enabled 0 = disabled R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Figure 44. Fault and Error Propagation Window In this case low OK line will signal DPM to pull other OK lines low to initiate shutdown of other POLs as programmed in the GUI Fault and Error Propagation window. If an error is propagated, the DPM can also generate commands to turn off a front end (a DC-DC converter generating the intermediate bus voltage) and trigger an optional crowbar protection to accelerate removal of the IBV voltage. 8.3.4.2 Propagation Process Propagation of a fault (OCP, UVP, OTP, and TRP) initiates regular turn-off of other POLs. The faulty POL in this case performs either the regular or the fast turn-off depending on a specific fault as described in section 8.3.2. Propagation of an error initiates fast turn-off of other POLs. The faulty POL performs the fast turn-off and turns on its low side switch. Figure 43. Protection Configuration Register PC3 In addition, the OK lines can be connected to the DPM to facilitate propagation of faults and errors between groups. One DPM can control up to 4 independent groups. To enable fault propagation between groups, the respective bit needs to be checked in the GUI Fault and Error Propagation window shown in Figure 44. Example of the fault propagation is shown in Figure 45 - Figure 46. In this three-output system (refer to the block diagram in Figure 25), the POL powering the output V3 (Ch 1 in the picture) encounters the undervoltage fault after the turn-on. When the fault propagation is not enabled, the POL turns off and generates the UV fault signal. Because the UV fault triggers the regular turn off, the POL meets its turnoff delay and falling slew rate settings during the turn-ff process as shown in Figure 45. Since the UV fault is programmed to be non-latching, the POL will attempt to restart every 130ms, repeating the process described above until the condition causing the undervoltage is removed. If the fault propagation between groups is enabled, the POL powering the output V3 pulls its OK line low and the DPM propagates the signal to the POL powering the output V1 that belongs to other group. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 24 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output The POL powering the output V1 (Ch3 in the picture) executes the regular turn-off. Since both V1 and V3 have the same delay and slew rate settings they will continue to turn off and on synchronously every 130ms as shown in Figure 46 until the condition causing the undervoltage is removed. The POL powering the output V2 continues to ramp up until it reaches its steady state level. 130ms is the interval from the instant of time when the output voltage ramps down to zero until the output voltage starts to ramp up again. Therefore, the 130ms hiccup interval is guaranteed regardless of the turn-off delay setting. Figure 46. Turn-On into UVP on V3. The UV Fault Is Programmed To Be Non-Latching and Propagate From Group C to Group A. Ch1 - V3 (Group C), Ch2 - V2, Ch3 - V1 (Group A) Summary of protections, their parameters and features are shown in Table 3 Figure 45. Turn-On into UVP on V3. The UV Fault Is Programmed To Be Non-Latching. Ch1 - V3 (Group C), Ch2 - V2, Ch3 - V1 (Group A) Table 3. Summary of Protections Parameters and Features Whenever VIN is applied Turn Off No Low Side Switch N/A Warning During steady state No N/A Tracking Fault During ramp up Fast OT Overtemperature Fault Whenever VIN is applied OC Overcurrent Fault UV Undervoltage OV Overvoltage Code Name Type When Active PT Warning PG Temperature Warning Power Good TR ZD-00194 Rev. 2.5, 01-Jul-10 Propagation Disable No Off Sends signal to DPM Sends signal to DPM Regular turn off Yes Regular Off Regular turn off No When VOUT exceeds prebias Fast Off Regular turn off No Fault During steady state Regular Off Regular turn off No Error When VOUT exceeds prebias Fast On Fast turn off No www.power-one.com Page 25 of 34 No ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8.4 PWM Parameters Z-Series POLs utilize the digital PWM controller. The controller enables users to program most of the PWM performance parameters, such as switching frequency, interleave, duty cycle, and feedback loop compensation. 8.4.1 Switching Frequency The switching frequency can be programmed in the GUI PWM Controller window shown in Figure 47 or directly via the I2C bus by writing into the INT register shown in Figure 48. Note that the content of the register can be changed only when the POL is turned off. Switching actions of all POLs connected to the SD line are synchronized to the master clock generated by the DPM. Each POL is equipped with a PLL and a frequency divider so they can operate at multiples (including fractional) of the master clock frequency as programmed by a user. The POL converters can operate at 500 kHz, 750 kHz, and 1 MHz. Although synchronized, switching frequencies of different POLs are independent of each other. It is permissible to mix POLs operating at different frequencies in one system. It allows optimizing efficiency and transient response of each POL in the system individually. R/W-0 R/W-0 R/W-0 R/W-0 1) R/W-0 1) R/W-0 1) R/W-0 1) R/W-0 1) FRQ2 FRQ1 FRQ0 INT4 INT3 INT2 INT1 INT0 Bit 7 Bit 0 Bit 7:5 FRQ[2:0] : PWM Frequency Selection 000: 500kHz 001: 750kHz 010: 1000lHz 011: 1250kHz 100: 1250kHz 101: 1500kHz 110: 1750kHz 111: 2000kHz R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Bit 4:0 INT[4:0] : Interleave position 00h: Ton starts with 0.0 Phase lag to SD Line 01h: Ton starts wi th 11.25 Phase lag to SD Line 02h: Ton starts with 22.50 Phase lag to SD Line ... 1Fh: Ton starts with 348.75 Phase lag to SD Line 1) Initial value depends on the state of the Interleave Mode ( IM) Input: IM=Open: At POR reset the 5 corresponding ADDRESS bits are loaded IM=Low: At POR reset a 0 is loaded Figure 48. Interleave Configuration Register INT 8.4.2 Interleave Interleave is defined as a phase delay between the synchronizing slope of the master clock on the SD pin and PWM signal of a POL. The interleave can be programmed in the GUI PWM Controller window or directly via the I2C bus by writing into the INT register. Every POL generates switching noise. If no interleave is programmed, all POLs in the system switch simultaneously and noise reflected to the input source from all POLs is added together as shown in Figure 49. Figure 49. Input Voltage Noise, No Interleave Figure 47. PWM Controller Window ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 26 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Figure 50 shows the input voltage noise of the threeoutput system with programmed interleave. Instead of all three POLs switching at the same time as in the previous example, the POLs V1, V2, and V3 switch at 67.5, 180, and 303.75, respectively. Noise is spread evenly across the switching cycle resulting in more than 1.5 times reduction. To achieve similar noise reduction without the interleave will require the addition of an external LC filter. Figure 52. Output Voltage Noise, Full Load, 180 Interleave Figure 50. Input Voltage Noise with Interleave Similar noise reduction can be achieved on the output of POLs connected in parallel. Figure 51 and Figure 52 show the output noise of two ZY7120s connected in parallel without and with 180 interleave, respectively. Resulting noise reduction is more than 2 times and is equivalent to doubling switching frequency or adding extra capacitance on the output of the POLs. The ZY7120 interleave feature is similar to that of multiphase converters, however, unlike in the case of multiphase converters, interleave does not have to be equal to 360/N, where N is the number of POLs in a system. ZY7120 interleave is independent of the number of POLs in a system and is fully programmable in 11.25 steps. It allows maximum output noise reduction by intelligently spreading switching energy. Note: Due to noise sensitivity issues that may occur in limited cases, it is recommended to avoid phase lag settings of 112.5 and 123.75 degrees, otherwise false PG and/or OV indications may occur. 8.4.3 Duty Cycle Limit The ZY7120 is a step-down converter therefore VOUT is always less than VIN. The relationship between the two parameters is characterized by the duty cycle and can be estimated from the following equation: V DC OUT , VIN .MIN Where, DC is the duty cycle, VOUT is the required maximum output voltage (including margining), VIN.MIN is the minimum input voltage. Figure 51. Output Voltage Noise, Full Load, No Interleave ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com It is good practice to limit the maximum duty cycle of the PWM controller to a somewhat higher value compared to the steady-state duty cycle as expressed by the above equation. This will further protect the output from excessive voltages. The duty cycle limit can be programmed in the GUI PWM Controller window or directly via the I2C bus by writing into the DCL register shown in Figure 53. Page 27 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output R/W-1 R/W-1 R/W-1 R/W-0 R/W-1 R/W-0 R/W-0 DCL5 DCL4 DCL3 DCL2 DCL1 DCL0 HI Bit 7 Bit 0: LO Bit 0 Bit 7:2 DCL[5:0], Duty Cycle Limitation 00h: 0 01h: 1/64 ... 3Fh: 63/64 Bit 1: R/W-0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset HI, ADC high saturation feed-forward 0: disabled 1: enabled The transfer function of the POL converter is shown in Figure 54. It is a third order function with two zeros and three poles. Pole 1 is the integrator pole, Pole 2 is used in conjunction with Zero 1 and Zero 2 to adjust the phase lead and limit the gain increase in mid band. Pole 3 is used as a high frequency lowpass filter to limit PWM noise. Magnitude[dB] Z1 50 LO, ADC low saturation feed-forward 0: disabled 1: enabled P1 Z2 P2 P3 P1: Pole 1 P2: Pole 3 P3: Pole 3 Z1: Zero 1 Z2: Zero 2 40 Figure 53. Duty Cycle Limit Register 30 20 8.4.4 ADC Saturation Feedforward To speed up the PWM response in case of heavy dynamic loads, the duty cycle can be forced either to 0 or the duty cycle limit depending on the polarity of the transient. This function is equivalent to having two comparators defining a window around the output voltage setpoint. When an error signal is inside the window, it will produce gradual duty cycle change proportional to the error signal. If the error signal goes outside the window (usually due to large output current steps), the duty cycle will change to its limit in one switching cycle. In most cases this will significantly improve transient response of the controller, reducing amount of required external capacitance. Under certain circumstances, usually when the maximum duty cycle limit significantly exceeds its nominal value, the ADC saturation can lead to the overcompensation of the output error. The phenomenon manifests itself as low frequency oscillations on the output of the POL. It can usually be reduced or eliminated by disabling the ADC saturation or limiting the maximum duty cycle to 120140% of the calculated value. It is not recommended to use ADC saturation for output voltages higher than 2.0V. 10 0.1 1 10 100 1000 0.1 1 10 100 1000 Freq [kHz] Phase [] +45 0 Freq [kHz] -45 -90 -135 -180 Figure 54. Transfer Function of PWM Positions of poles and zeroes are determined by coefficients of the digital filter. The filter is characterized by four numerator coefficients (C0, C1, C2, C3) and three denominator coefficients (B1, B2, B3). The coefficients are automatically calculated when desired frequency of poles and zeros is entered in the GUI PWM Controller window. The coefficients are stored in the C0H, C0L, C1H, C1L, C2H, C2L, C3H, C3L, B1, B2, and B3 registers. Note: The GUI automatically transforms zero and pole frequencies into the digital filter coefficients. It is strongly recommended to use the GUI to determine the filter coefficients. The ADC saturation feedforward can be programmed in the GUI PWM Controller window or directly via the I2C bus by writing into the DCL register. Programming feedback loop compensation allows optimizing POL performance for various application conditions. For example, increase in bandwidth can significantly improve dynamic response. 8.4.5 Feedback Loop Compensation Feedback loop compensation can be programmed in the GUI PWM Controller window by setting frequency of poles and zeros of the transfer function. 8.5 ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Current Share The POL converters are equipped with the digital current share function. To activate the current share, interconnect the CS pins of the POLs connected in Page 28 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output parallel. The digital signal transmitted over the CS line sets output currents of all POLs to the same level. When POLs are connected in parallel, they must be included in the same parallel bus in the GUI System Configuration window shown in Figure 55. In this case, the GUI automatically copies parameters of one POL onto all POLs connected to the parallel bus. It makes it impossible to configure different performance parameters for POLs connected in parallel except for interleave and load regulation settings that are independent. The interleave allows to reduce and move the output noise of the converters connected in parallel to higher frequencies as shown in Figure 51 and Figure 52. The load regulation allows controlling the current share loop gain in case of small signal oscillations. It is recommended to always add a small amount of load regulation to one of the converters connected in parallel to reduce loop gain and therefore improve stability. 8.6 Performance Parameters Monitoring The output voltage is measured at the output sense pins, output current is measured using the ESR of the output inductor and temperature is measured by the thermal sensor built into the controller IC. Output current readings are adjusted based on temperature readings to compensate for the change of ESR of the inductor with temperature. An 8-Bit Analog to Digital Converter (ADC) converts the output voltage, output current, and temperature into a digital signal to be transmitted via the serial interface. The ADC allows a minimum sampling frequency of 1 kHz for all three values. Monitored parameters are stored in registers (VOM, IOM, and TMON) that are continuously updated. If the Retrieve Monitoring bits in the GUI Group Configuration window shown in Figure 56 are checked, those registers are being copied into the ring buffer located in the DPM. Contents of the ring buffer can be displayed in the GUI IBS Monitoring Window shown in Figure 57 or it can be read directly via the I2C bus using high and low level commands as described in the `"DPM Programming Manual". The POL converters can monitor their own performance parameters such as output voltage, output current, and temperature. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 29 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Figure 55. GUI System Configuration Window ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 30 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output Figure 56. POL Group Configuration Window 9. Safety The ZY7120 POL converters do not provide isolation from input to output. The input devices powering ZY7120 must provide relevant isolation requirements according to all IEC60950 based standards. Nevertheless, if the system using the converter needs to receive safety agency approval, certain rules must be followed in the design of the system. In particular, all of the creepage and clearance requirements of the end-use safety ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com requirements must be observed. These requirements are included in UL60950 - CSA6095000 and EN60950, although specific applications may have other or additional requirements. The ZY7120 POL converters have no internal fuse. If required, the external fuse needs to be provided to protect the converter from catastrophic failure. Refer to the "Input Fuse Selection for DC/DC converters" application note on www.power-one.com for proper selection of the input fuse. Both input traces and the Page 31 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output chassis ground trace (if applicable) must be capable of conducting a current of 1.5 times the value of the fuse without opening. The fuse must not be placed in the grounded input line. Abnormal and component failure tests were conducted with the POL input protected by a fastacting 65 V, 15 A, fuse. If a fuse rated greater than 15 A is used, additional testing may be required. In order for the output of the ZY7120 POL converter to be considered as SELV (Safety Extra Low Voltage), according to all IEC60950 based standards, the input to the POL needs to be supplied by an isolated secondary source providing a SELV also. Figure 57. IBS Monitoring Window ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 32 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 10. Mechanical Drawings All Dimensions are in mm Tolerances: 0.5-10 0.1 10-100 0.2 Pin Coplanarity: 0.1 max 10 SMT Pickup Tab 140.3 13.4 2.5 3.4 0.6 1.27 (x10) 0.6 0.4 (x20) 1.27 (x10) 2.54 0.25 1.5 4.3 27.94 2.03 Tilt Specification: <5 from vertical, after assembly 320.3 9.75 12 12 10.25 9.1 3.5 8.250.3 1.50.1 3.25 Pin 1 15.75 SMT Pickup Center Point Figure 58. Mechanical Drawing Figure 59. Pinout Diagram (Bottom View) ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 33 of 34 ZY7120 20A DC-DC Intelligent POL Data Sheet 3V to 13.2V Input 0.5V to 5.5V Output 8.6 32 4 10 1.2 10 6 (x 3) Unexposed thermal copper area associated with each pad must be free from other traces 6 9 1.8 (x 22) Pin 1 2 1.27 (x 10) 2.54 1.27 (x 10) 2.03 0.8 Figure 60. Recommended Pad Sizes Figure 61. Recommended PCB Layout for Multilayer PCBs Notes: 1. NUCLEAR AND MEDICAL APPLICATIONS - Power-One products are not designed, intended for use in, or authorized for use as critical components in life support systems, equipment used in hazardous environments, or nuclear control systems without the express written consent of the respective divisional president of Power-One, Inc. 2. TECHNICAL REVISIONS - The appearance of products, including safety agency certifications pictured on labels, may change depending on the date manufactured. Specifications are subject to change without notice. 2 I C is a trademark of Philips Corporation. ZD-00194 Rev. 2.5, 01-Jul-10 www.power-one.com Page 34 of 34