Enpirion(R) Power Datasheet EN2392QI 9A PowerSoC Voltage Mode Synchronous Buck With Integrated Inductor Not Recommended for New Designs Description Features The EN2392QI is a Power System on a Chip (PowerSoC) DC-DC converter. It integrates MOSFET switches, small-signal control circuits, compensation and an integrated inductor in an advanced 11x10x3mm QFN module. It offers high efficiency, excellent line and load regulation over temperature. The EN2392QI operates over a wide input voltage range and is specifically designed to meet the precise voltage and fast transient requirements of highperformance products. The EN2392QI features frequency synchronization to an external clock, power OK output voltage monitor, programmable soft-start along with thermal and over current protection. The device's advanced circuit design, ultra high switching frequency and proprietary integrated inductor technology delivers high-quality, ultra compact, nonisolated DC-DC conversion. * * * * Integrated Inductor, MOSFETS, Controller Total Solution Size Estimate: 235mm2 Wide Input Voltage Range: 4.5V - 13.2V 1% Initial Output Voltage Accuracy * * * * * * * * * * Master/Slave Parallel Operation (up to 4 devices) Frequency Synchronization (External Clock) Output Enable Pin and Power OK Signal Programmable Soft-Start Time Pin Compatible with EN2390QI Under Voltage Lockout Protection (UVLO) Over Current and Short Circuit Protection Pre-Bias Startup Protection Thermal Soft-Shutdown Protection RoHS Compliant, MSL Level 3, 260oC Reflow Applications The Altera Enpirion solution significantly helps in system design and productivity by offering greatly simplified board design, layout and manufacturing requirements. In addition, overall system level reliability is improved given the small number of components required with the Altera Enpirion solution. * * * * * All Altera Enpirion products are RoHS compliant, halogen free and are compatible with lead-free manufacturing environments. Space Constrained Applications Distributed Power Architectures Output Voltage Ripple Sensitive Applications Beat Frequency Sensitive Applications Servers, Embedded Computing Systems, LAN/SAN Adapter Cards, RAID Storage Systems, Industrial Automation, Test and Measurement, and Telecommunications Efficiency vs. Output Current 0.22F 47nF 100 BTMP VDDB PVIN EN2392QI 4.75k ON OFF 2x 22F 1206 VOUT BGND VOUT 80 SW CA 4.7 EAIN ENABLE REA 680pF COUT CBULK RA R CA AVINO 1F AVIN 1F 47nF VFB SS M/S EN_PB PGND FQADJ RFS PGND AGND RCLX RB 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V VOUT = 1.0V 10 CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply 0 RCLX 0 1 2 3 4 5 6 OUTPUT CURRENT (A) 7 8 9 Figure 2. Highest Efficiency in Smallest Solution Size Figure 1. Simplified Application Circuit 10107 90 Optional EFFICIENCY (%) PG VIN June 2, 2015 Rev C EN2392QI Ordering Information Part Number EN2392QI EVB-EN2392QI Package Markings EN2392QI EN2392QI TAMBIENT Rating (C) -40 to +85 Package Description 76-pin (11mm x 10mm x 3mm) QFN T&R QFN Evaluation Board Packing and Marking Information: www.altera.com/support/reliability/packing/rel-packing-and-marking.html FQADJ RCLX SS EAIN VFB 66 65 64 63 62 POK NC 67 57 EN_PB 68 ENABLE NC(SW) 69 58 NC(SW) 70 AVIN NC(SW) 71 59 NC 72 AGND NC 73 60 NC 74 M/S NC 75 61 NC 76 Pin Assignments (Top View) 56 S_OUT 2 55 S_IN NC 3 54 BGND NC 4 53 VDDB NC 5 52 BTMP NC 6 51 PG NC 7 50 AVINO NC 8 49 PVIN NC 9 48 PVIN NC 10 47 PVIN NC 11 46 PVIN NC 12 45 PVIN NC 13 44 PVIN NC 14 43 PVIN NC 15 42 PVIN NC 16 41 PVIN NC 17 40 PVIN NC 18 39 PVIN KEEP OUT 38 35 PGND PGND 34 PGND 37 33 PGND PGND 32 NC(SW) 36 31 NC(SW) PGND 30 NC 26 VOUT 29 25 VOUT NC 24 VOUT 28 23 VOUT 77 PGND VOUT 22 VOUT 27 21 VOUT VOUT 20 KEEP OUT VOUT NC KEEP OUT 19 1 NC NC Figure 3: Pin Out Diagram (Top View) NOTE A: NC pins are not to be electrically connected to each other or to any external signal, ground, or voltage. All pins including NC pins must be soldered to the PCB. Failure to follow this guideline may result in part malfunction or damage. NOTE B: Shaded area highlights exposed metal below the package that is not to be mechanically or electrically connected to the PCB. Refer to Figure 16 for details. NOTE C: White `dot' on top left is pin 1 indicator on top of the device package. www.altera.com/enpirion Page 2 10107 June 2, 2015 Rev C EN2392QI Pin Description I/O Legend: P=Power PIN 1-19, 29, 30, 67, 7276 NAME I/O NC NC 20-28 VOUT O 31, 32, 6971 NC(SW) NC 33-38 PGND G 39-49 PVIN P 50 AVINO O 51 52 PG BTMP I/O I/O 53 VDDB O 54 BGND G 55 S_IN I 56 S_OUT O 57 POK O 58 ENABLE I 59 AVIN P 60 AGND G 61 M/S 62 VFB I/O 63 EAIN I 64 SS I/O 65 RCLX I/O 66 FQADJ I/O 68 EN_PB I 77 PGND G G=Ground NC=No Connect I=Input O=Output I/O=Input/Output FUNCTION NO CONNECT - These pins may be internally connected. Do not connect them to each other or to any other electrical signal. Failure to follow this guideline may result in device damage. Regulated converter output. Connect these pins to the load and place output capacitor betw een these pins and PGND pins 33-35. Sw itching node - These pins are internally connected to the common sw itching node of the internal MOSFETs. In applications w here the total output capacitance exceeds 50% of the maximum allow ed, a "snubber" circuit consisting of a series 4.7 resistor and a 680pF capacitor should be connected from the NC(SW) pin to the PGND. See Output Capacitor Selection for details. Input/output pow er ground. Connect these pins to the ground electrode of the input and output filter capacitors. See VOUT and PVIN pin descriptions for more details. Input pow er supply. Connect to input pow er supply. Decouple w ith input capacitor to PGND pins 3638. Internal 3.4V linear regulator output. Connect this pin to AVIN for applications w here operation from a single input voltage (PVIN) is required. If AVINO is being used, place a 1F, X5R, capacitor betw een AVINO and AGND as close as possible to AVINO. PMOS gate. Place a 47nF, X5R, capacitor betw een this pin and BTMP. Bottom plate ground. See pin 51 description. Internal regulated voltage used for the internal control circuitry. Place a 0.22F, X5R, capacitor betw een this pin and BGND. Ground for VDDB. Do not connect BGND to any other ground. See pin 53 description. Digital synchronization input. This pin accepts either an input clock to phase lock the internal sw itching frequency or a S_OUT signal from another EN2392QI. Leave this pin floating if not used. Digital synchronization output. PWM signal is output on this pin. Leave this pin floating if not used. Pow er OK is an open drain transistor (pulled up to AVIN or similar voltage) used for pow er system state indication. POK is logic high w hen VOUT is w ithin -10% to +20% of VOUT nominal. Leave this pin floating if not used. Output enable. Applying a logic high to this pin enables the output and initiates a soft-start. Applying a logic low disables the output. ENABLE logic cannot be higher than AVIN (refer to Absolute Maximum Ratings). Do not leave floating. See Pow er Up/Dow n Sequencing section for details. 3.3V Input pow er supply for the controller. Place a 1F, X5R, capacitor betw een AVIN and AGND Analog ground. This is the ground return for the controller. All AGND pins need to be connected to a quiet ground. A logic level low configures the device as Master and a logic level high configures the device as a Slave. Connect to ground in standalone mode. External feedback input. The feedback loop is closed through this pin. A voltage divider at VOUT is used to set the output voltage. The mid-point of the divider is connected to VFB. A phase lead netw ork from this pin to VOUT is also required to stabilize the loop. Optional error amplifier input. Allow s for customization of the control loop for performance optimization. Leave this pin floating if not used. Soft-start node. The soft-start capacitor is connected betw een this pin and AGND. The value of this capacitor determines the startup time. See Soft-Start Operation in the Functional Description section for details. Over-current protection setting. Placement of a resistor on this pin w ill adjust the over-current protection threshold. See Table 2 for the recommended RCLX Value to set OCP at the nominal value specified in the Electrical Characteristics table. Do not leave this pin floating. Adding a resistor (RFS) to this pin w ill adjust the sw itching frequency of the EN2392QI. See Table 1 for suggested resistor values on RFS for various PVIN/VOUT combinations to maximize efficiency. Do not leave this pin floating. Enable pre-bias protection. Connect EN_PB directly to AVIN to enable the Pre-Bias Protection feature. Pull EN_PB directly to ground to disable the feature. Do not leave this pin floating. See PreBias Operation for details. Not a perimeter pin. Device thermal pad to be connected to the system GND plane for heat-sinking purposes. www.altera.com/enpirion Page 3 10107 June 2, 2015 Rev C EN2392QI Absolute Maximum Ratings CAUTION: Absolute Maximum ratings are stress ratings only. Functional operation beyond the recommended operating conditions is not implied. Stress beyond the absolute maximum ratings may impair device life. Exposure to absolute maximum rated conditions for extended periods may affect device reliability. MIN MAX UNITS Pin Voltages - PVIN, VOUT, PG PARAMETER SYMBOL -0.5 15 V Pin Voltages - ENABLE, S_IN, M/S, POK, EN_PB -0.5 AVIN + 0.3 V Pin Voltages - AVINO, AVIN, ENABLE, S_IN, S_OUT, M/S -0.5 6.0 V Pin Voltages - VFB, SS, EAIN, RCLX, FQADJ, VDDB, BTMP -0.5 2.75 V Dual Supply PVIN Rising and Falling Slew Rate (Note 1) 25 V/ms Single Supply PVIN Rising and Falling Slew Rate (Note 1, 2) 10 V/ms 150 C 150 C 260 C 2000 V Storage Temperature Range TSTG Maximum Operating Junction Temperature -65 TJ-ABS Max Reflow Temp, 10 Sec, MSL3 JEDEC J-STD-020A ESD Rating (based on Human Body Model) Recommended Operating Conditions SYMBOL MIN MAX UNITS Input Voltage Range PARAMETER PVIN 4.5 13.2 V AVIN: Controller Supply Voltage AVIN 2.5 5.5 V Output Voltage Range (Note 3) VOUT 0.75 3.3 V Output Current IOUT 0 9 A Operating Ambient Temperature TA -40 +85 C Operating Junction Temperature TJ -40 +125 C Thermal Characteristics PARAMETER SYMBOL TYP UNITS Thermal Resistance: Junction to Ambient (0 LFM) (Note 4) JA 15 C/W Thermal Resistance: Junction to Case (0 LFM) JC 1.5 C/W Thermal Shutdown TSD 150 C Thermal Shutdown Hysteresis TSDH 35 C Note 1: PVIN rising and falling slew rates cannot be outside of specification. PVIN should rise monotonically into regulation. Filter PVIN with proper input bulk capacitance so that the input AC ripple in regulation is less than 1V of the regulation voltage. See Input Capacitor Selection for details. Note 2: For accurate power up sequencing, use a fast ENABLE logic (>3V/100s) after both AVIN and PVIN are high. Tying ENABLE to AVIN may result in a startup delay due to a slow ENABLE logic. Note 3: Dropout: Maximum VOUT VIN - 2.5V Note 4: Based on 2oz. external copper layers and proper thermal design in line with EIJ/JEDEC JESD51-7 standard for high thermal conductivity boards. www.altera.com/enpirion Page 4 10107 June 2, 2015 Rev C EN2392QI Electrical Characteristics NOTE: VIN=12V, Minimum and Maximum values are over operating ambient temperature range unless otherwise noted. Typical values are at TA = 25C. PARAMETER SYMBOL Operating Input Voltage PVIN Controller Input Voltage AVIN TEST CONDITIONS MIN TYP MAX UNITS 4.5 13.2 V 3 5.5 V AVIN Under Voltage Lock-out rising AVINUVLOR Voltage above which UVLO is not asserted 2.5 2.75 3 V AVIN Under Voltage Lock-out falling AVINOVLOF Voltage below which UVLO is asserted 2.1 2.35 2.6 V AVIN pin Input Current Internal Linear Regulator Output Voltage IAVIN 11 mA AVINO 3.4 V IPVINS PVIN=12V, AVIN=3.4V, ENABLE=0V 2 mA IAVINS PVIN=12V, AVIN=3.4V, ENABLE=0V 300 A Feedback Pin Voltage VFB Feedback Pin Voltage VFB Feedback pin Input Leakage Current IFB Feedback node voltage at: VIN = 12V, ILOAD = 0, TA = 25C Only Feedback node voltage at: 4.5V VIN 13.2V 0A ILOAD 9A, TA = -40 to 85C VFB pin input leakage current (Note 5) Shut-Down Supply Current VOUT Rise Time Soft Start Capacitor Range Output Capacitance Range Continuous Output Current Over Current Trip Level tRISE CSS = 47nF (Note 5, Note 6, Note 7) IOUT_MAX_CONT IOCP 0.60 0.606 V 0.588 0.60 0.612 V 5 nA -5 1.96 2.8 3.64 ms 10 47 68 nF VIN = 12V VOUT = 3.3V; RFS = 22k See Table 3 for other output voltages (Note 5) 80 200 800 F VIN = 12V VOUT 1.0V; RFS = 3.01k See Table 3 for other output voltages (Note 5) 80 200 2200 F 9 A CSS_RANGE COUT 0.594 Subject to thermal de-rating VIN = 12V 0 9.2 12 Short Circuit Average Input Current IIN_OCP ENABLE Logic High VENABLE_HIGH 4.5V VIN 13.2V; (Note 2) ENABLE Logic Low VENABLE_LOW 4.5V VIN 13.2V; ENABLE Hysteresis ENHYS 200 mV TENLOCKOUT 8 ms ENABLE Lockout Time Short = 10m (Note 8) 100 mA 1.25 AVIN V 0 0.95 V www.altera.com/enpirion Page 5 10107 June 2, 2015 Rev C EN2392QI PARAMETER ENABLE pin Input Current SYMBOL IENABLE TEST CONDITIONS TYP MAX UNITS AVIN = 5.5V ENABLE = 1.8V; ENABLE = 3.3V; ENABLE = 5.5V; 5 11 23 8 18 32 A RFS = 3.01k 1.0 Switching Frequency FSW External SYNC Clock Frequency Lock Range FPLL_LOCK Range of SYNC clock frequency (See Table 1) S_IN Threshold - Low VS_IN_LO S_IN Clock Logic Low Level (Note 5) S_IN Threshold - High VS_IN_HI S_IN Clock Logic High Level (Note 5) S_OUT Threshold - Low VS_OUT_LO S_OUT Clock Logic Low Level (Note 5) S_OUT Threshold - High VS_OUT_HI S_OUT Clock Logic High Level (Note 5) POKLT Percentage of Nominal Output Voltage for POK to be Low POK Lower Threshold MIN 0.9 1.8 1.8 MHz 1.8 MHz 0.8 V 2.5 V 0.8 V 2.5 V 90 % POK Output low Voltage VPOKL With 4mA Current Sink into POK 0.4 V POK Output Hi Voltage VPOKH PVIN Range: 4.5V VIN 13.2V AVIN V 1 A 0.8 V POK pin VOH leakage current IPOKL POK High (Note 5) M/S Pin Logic Low VT-LOW Tie Pin to GND M/S Pin Logic High VT-HIGH Pull up to AVIN Through an External Resistor REXT M/S Pin Input Current Note Note Note Note 5: 6: 7: 8: IM/S REXT = 15k; AVIN = 3.4V; AVIN = 5.5V; 1.8 V 65 175 A Parameter not production tested but is guaranteed by design. Rise time calculation begins when AVIN > VUVLO and ENABLE = HIGH. VOUT Rise Time Accuracy does not include soft-start capacitor tolerance. Output short circuit condition was performed with load impedance that is greater than or equal to 10m. www.altera.com/enpirion Page 6 10107 June 2, 2015 Rev C EN2392QI Typical Performance Curves Efficiency vs. Output Current 100 90 90 80 80 EFFICIENCY (%) EFFICIENCY (%) Efficiency vs. Output Current 100 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V 10 VOUT = 1.0V CONDITIONS VIN = 12.0V Single Supply 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V 0 0 0 1 5 2 3 4 6 OUTPUT CURRENT (A) 7 8 9 0 MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) 9 8 7 6 4 3 CONDITIONS VIN = 12V TJMAX = 125C JA = 15C/W 11x10x3mm QFN No Air Flow VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 8 7 3 9 8 7 6 5 4 3 VOUT = 1.0V CONDITIONS VIN = 12V TJMAX = 125C JA = 12.5C/W 11x10x3mm QFN Air Flow (200fpm) VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) 9 4 8 Output Current De-rating with Heat Sink 10 5 7 9 Output Current De-rating with Air Flow (400fpm) CONDITIONS VIN = 12V TJMAX = 125C JA = 11C/W 11x10x3mm QFN Air Flow (400fpm) 2 3 4 5 6 OUTPUT CURRENT (A) 10 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) 6 1 Output Current De-rating with Air Flow (200fpm) Output Current De-rating 10 5 VOUT = 1.0V 10 CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) 10 9 8 7 6 5 4 3 CONDITIONS VIN = 12V TJMAX = 125C JA = 14C/W 11x10x3mm QFN Heat Sink - Wakefield Thermal Solutions P/N 651-B VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) www.altera.com/enpirion Page 7 10107 June 2, 2015 Rev C EN2392QI Typical Performance Curves Output Current De-rating w/ Heat Sink and Air Flow (400fpm) MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) Output Current De-rating w/ Heat Sink and Air Flow (200fpm) 10 9 8 CONDITIONS VIN = 12V TJMAX = 125C JA = 11.5C/W 11x10x3mm QFN 7 6 Air Flow (200fpm) Heat Sink - Wakefield Thermal Solutions P/N 651-B 5 4 3 VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 10 9 8 CONDITIONS VIN = 12V TJMAX = 125C JA = 10C/W 11x10x3mm QFN 7 6 5 Air Flow (400fpm) Heat Sink - Wakefield Thermal Solutions P/N 651-B 4 3 VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 2 Output Voltage vs. Output Current Output Voltage vs. Output Current 1.005 1.205 1.004 VIN = 8V 1.003 VIN = 10V 1.002 VIN = 12V OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) VOUT = 1.2V 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (C) 1.001 1.000 0.999 0.998 0.997 1.204 VIN = 8V 1.203 VIN = 10V 1.202 VIN = 12V 1.201 1.200 1.199 1.198 1.197 CONDITIONS VOUT_NOM = 1.0V 0.996 CONDITIONS VOUT_NOM = 1.2V 1.196 0.995 1.195 0 1 2 3 4 5 6 7 OUTPUT CURRENT (A) 8 9 0 1 2 3 4 5 6 7 OUTPUT CURRENT (A) 8 9 Output Voltage vs. Output Current Output Voltage vs. Output Current 2.505 1.805 VIN = 8V 1.804 1.803 VIN = 10V 1.802 VIN = 12V OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) VOUT = 1.0V 1.801 1.800 1.799 1.798 1.797 VIN = 8V 2.503 VIN = 10V 2.502 VIN = 12V 2.501 2.500 2.499 2.498 2.497 CONDITIONS VOUT_NOM = 1.8V 1.796 2.504 CONDITIONS VOUT_NOM = 2.5V 2.496 2.495 1.795 0 1 2 3 4 5 6 7 OUTPUT CURRENT (A) 8 9 0 1 2 3 4 5 6 7 OUTPUT CURRENT (A) 8 9 www.altera.com/enpirion Page 8 10107 June 2, 2015 Rev C EN2392QI Typical Performance Curves Output Voltage vs. Temperature Output Voltage vs. Temperature 1.204 CONDITIONS VIN = 14V VOUT_NOM = 1.2V 1.203 1.202 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) 1.204 1.201 1.200 LOAD = 0A 1.199 LOAD = 2A LOAD = 4A 1.198 LOAD = 6A 1.197 CONDITIONS VIN = 12V VOUT_NOM = 1.2V 1.203 1.202 1.201 1.200 LOAD = 0A 1.199 LOAD = 2A LOAD = 4A 1.198 LOAD = 6A 1.197 LOAD = 9A LOAD = 9A 1.196 1.196 -40 35 60 -15 10 AMBIENT TEMPERATURE ( C) -40 85 85 Output Voltage vs. Temperature Output Voltage vs. Temperature 1.204 1.204 CONDITIONS VIN = 10V VOUT_NOM = 1.2V 1.203 1.202 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) -15 10 35 60 AMBIENT TEMPERATURE ( C) 1.201 1.200 LOAD = 0A 1.199 LOAD = 1A LOAD = 2A 1.198 LOAD = 3A 1.197 CONDITIONS VIN = 8V VOUT_NOM = 1.2V 1.203 1.202 1.201 1.200 LOAD = 0A 1.199 LOAD = 1A LOAD = 2A 1.198 LOAD = 3A 1.197 LOAD = 4A LOAD = 4A 1.196 1.196 -40 -15 10 35 60 AMBIENT TEMPERATURE ( C) 85 -40 -15 10 35 60 AMBIENT TEMPERATURE ( C) 85 INDIVIDUAL OUTPUT CURRENT (A) Parallel Current Share Breakdown 10 9 8 MASTER 7 SLAVE 6 IDEAL 5 4 CONDITIONS EN2390QI VIN = 12V VOUT = 1.2V 3 2 1 0 2 4 6 8 10 12 14 TOTAL OUTPUT CURRENT (A) 16 www.altera.com/enpirion Page 9 10107 June 2, 2015 Rev C EN2392QI Typical Performance Characteristics Enable Startup/Shutdown Waveform (0A) Enable Startup/Shutdown Waveform (3A) ENABLE ENABLE VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 0A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 3A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) Enable Startup/Shutdown Waveform (6A) Enable Startup/Shutdown Waveform (9A) ENABLE ENABLE VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 6A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 9A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) Power Up Waveform (0A) Power Up Waveform (4.5A) PVIN PVIN VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 9A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 4.5A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) www.altera.com/enpirion Page 10 10107 June 2, 2015 Rev C EN2392QI Typical Performance Characteristics Power Up Waveform (6A) Power Up Waveform (9A) PVIN PVIN VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 6A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) CONDITIONS VIN = 12V, VOUT = 1.8V, Load = 9A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) Output Ripple at 20MHz Bandwidth VOUT = 1V (AC Coupled) Output Ripple at 20MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 0A VOUT = 1.8V (AC Coupled) VOUT = 1.8V (AC Coupled) VOUT = 3.3V (AC Coupled) VOUT = 3.3V (AC Coupled) 20mV / DIV 20mV / DIV CONDITIONS VIN = 12V, CIN = 2x22F (1206), COUT = 2x47F + 100F (1206) CONDITIONS VIN = 12V, CIN = 2x22F (1206), COUT = 2x47F + 100F (1206) Output Ripple at 500MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 9A Output Ripple at 500MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 0A VOUT = 1.8V (AC Coupled) VOUT = 1.8V (AC Coupled) VOUT = 3.3V (AC Coupled) VOUT = 3.3V (AC Coupled) 20mV / DIV 20mV / DIV CONDITIONS VIN = 12V, CIN = 2x22F (1206), COUT = 2x47F + 100F (1206) LOAD = 9A CONDITIONS VIN = 12V, CIN = 2x22F (1206), COUT = 2x47F + 100F (1206) www.altera.com/enpirion Page 11 10107 June 2, 2015 Rev C EN2392QI Typical Performance Characteristics Load Transient from 0 to 3A (VOUT =1V) Load Transient from 0 to 4.5A (VOUT =1V) VOUT (AC Coupled) VOUT (AC Coupled) CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration LOAD LOAD Load Transient from 0 to 6A (VOUT =1V) Load Transient from 0 to 9A (VOUT =1V) VOUT (AC Coupled) VOUT (AC Coupled) CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration LOAD LOAD CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration Load Transient from 0 to 3A (VOUT =3.3V) Load Transient from 0 to 4.5A (VOUT =3.3V) VOUT (AC Coupled) VOUT (AC Coupled) CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration LOAD LOAD www.altera.com/enpirion Page 12 10107 June 2, 2015 Rev C EN2392QI Typical Performance Characteristics Load Transient from 0 to 6A (VOUT =3.3V) Load Transient from 0 to 9A (VOUT =3.3V) VOUT (AC Coupled) VOUT (AC Coupled) LOAD CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration LOAD CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 2x22F (1206) COUT = 2 x 47F (1206) + 100F (1206) Using Best Performance Configuration Pre-Bias Shutdown Waveform Pre-Bias Startup Waveform PVIN = 12V PVIN = 12V ENABLE ENABLE VOUT VOUT Max Pre-Bias <100% of Nominal VOUT is held low CONDITIONS VIN = 12V (Single Supply Only) VOUT = 1.0V, Load = 0A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) for another ~6ms CONDITIONS VIN = 12V (Single Supply Only) VOUT = 1.0V, Load = 0A, Css = 47nF CIN = 2x22F(1206), COUT = 2x47F(1206)+100F(1206) www.altera.com/enpirion Page 13 10107 June 2, 2015 Rev C EN2392QI Functional Block Diagram M/S S_OUT S_IN UVLO Digital I/O BTMP PVIN PG Linear Regulator To PLL AVINO Thermal Limit Current Limit NC(SW) Gate Drive VOUT 7.5k BGND (-) PWM Comp (+) PGND PLL/Sawtooth Generator FQADJ VDDB Compensation Network EAIN Compensation Network (-) Error Amp (+) Power Good Logic ENABLE POK 300k 180k SS Soft Start VFB Voltage Reference Generator Band Gap Reference EN2392QI AVIN EN_PB AGND Figure 4: Functional Block Diagram Functional Description small size input and output filter capacitors, as well as a wide loop bandwidth within a small foot print. Synchronous Buck Converter The EN2392QI is a highly integrated synchronous, buck converter with integrated controller, power MOSFET switches and integrated inductor. The nominal input voltage (PVIN) range is 4.5V to 13.2V and can support up to 9A of continuous output current. The output voltage is programmed using an external resistor divider network. The control loop utilizes a Type IV Voltage-Mode compensation network and maximizes on a low-noise PWM topology. Much of the compensation circuitry is internal to the device. However, a phase lead capacitor is required along with the output voltage feedback resistor divider to complete the Type IV compensation network.. The high switching frequency of the EN2392QI enables the use of Protection Features: The power supply has the following protection features: * Over Current and Short Circuit Protection * Thermal Soft-Shutdown with Hysteresis * AVIN Under-Voltage Lockout Protection * Pre-Bias Protection Additional Features: * * * Switching Frequency Synchronization. Programmable Soft-Start Power OK Output Monitoring www.altera.com/enpirion Page 14 10107 June 2, 2015 Rev C EN2392QI Modes of Operation ENABLE Operation The EN2392QI is designed to be powered by either a single input supply (PVIN) or two separate supplies: one for PVIN and the other for AVIN. The EN2392QI is not "hot pluggable." Refer to the PVIN Slew Rate specification on page 4. The ENABLE pin provides a means to enable normal operation or to shut down the device. A logic high will enable the converter into normal operation. When the ENABLE pin is asserted (high) the device will undergo a normal soft-start. A logic low will disable the converter. A logic low will power down the device in a controlled manner and the device is subsequently shut down. The ENABLE signal has to be low for at least the ENABLE Lockout Time (8ms) in order for the device to be reenabled. To ensure accurate startup sequencing the ENABLE/DISABLE signal should be faster than 3V/100s. A slower ENABLE/DISABLE signal may result in a delayed startup and shutdown response. Do not leave ENABLE floating. Single Input Supply Application (PVIN Only): 0.22F 47nF PG VIN BTMP VDDB PVIN EN2392QI 10k 4.75k C OUT EAIN ENABLE 2x 22F 1206 VOUT BGND VOUT RA CA 2.26k AVINO 1F REA AVIN 1F 47nF RCA VFB SS M/S EN_PB PGND Pre-Bias Operation PGND FADJ RFS RB RCLX AGND RCLX Figure 5: Single Input Supply Schematic In single input supply mode, the EN2392QI only requires one input voltage rail (typically 12V). The EN2392QI has an internal linear regulator that converts PVIN to 3.3V. The output of the linear regulator is provided on the AVINO pin once the device is enabled. AVINO should be connected to AVIN. Also, in this single supply application, place a resistor (RVB) between VDDB and AVIN, as shown in Figure 5. Altera recommends RVB=4.75k. Dual Input Supply Application (PVIN and AVIN): 0.22F 47nF PG VIN BTMP VDDB PVIN VOUT BGND VOUT EN2392QI ON 2x 22F 1206 OFF VAVIN COUT EAIN ENABLE AVINO RA AVIN 1F 47nF CA REA RCA VFB SS M/S EN_PB PGND FQADJ RFS PGND AGND RCLX RB RCLX Figure 6: Dual Input Supply Schematic In dual input supply mode, two input voltage rails are required (typically 12V for PVIN and 3.3V for AVIN). Refer to Figure 6 for the recommended schematic for a dual input supply application. Since AVINO is not used, it can be left open. The EN2392QI has a Pre-Bias feature which will allow the regulator to startup into a pre-charged output. The pre-biased output voltage must be below the nominal regulation voltage; otherwise, damage may occur during startup and shutdown. To use this feature, the EN2392QI must be configured to Single Supply mode, set to standalone operation (no parallel operation) and follow the instructions below: * The EN_PB pin must be pulled high to AVIN * A resistor divider must be connected from PVIN to ENABLE to Ground (10k on top, 2.26k on the bottom) to ensure proper shutdown. The resistor divider will disable the device when PVIN falls below approximately 6.8V. The resistor divider values may be adjusted accordingly to meet PVIN requirements. See Figure X. * PVIN rail should be in regulation (>4.5V) prior to being enabled. * Since the ENABLE pin is tied to the resistor divider to PVIN, an open drain (such as the POK signal of another regulator or Sequencer) should be tied to ENABLE in order to keep the device disabled while the PVIN rail rises into regulation. * Once the PVIN rail is in regulation, the ENABLE may be pulled high through the resistor divider. * The ENABLE rise time must be faster than 3V/100us. The output will start up from the Pre-Bias voltage into regulation monotonically if the instructions are followed; otherwise, the Pre-Bias Protection feature may not function properly and the device will startup into a Pre-Bias output voltage. Starting up www.altera.com/enpirion Page 15 10107 June 2, 2015 Rev C EN2392QI 47nF Need Fast ENABLE Logic (>3V/100us) VIN PG 0.22F BTMP VDDB PVIN 10k EN2392QI 4.75k 2x 22F 1206 VOUT BGND VOUT COUT EAIN ENABLE RA 2.26k AVINO 1F 1.600 1.400 1.200 1.000 0.600 0 VFB SS 2 4 6 8 10 12 14 16 18 20 22 RFS RESISTOR VALUE (k) Figure 9. RFS versus Switching Frequency M/S PGND PGND FQADJ AGND RFS CONDITIONS VIN = 6V to 12V VOUT = 0.8V to 3.3V 0.800 RCA EN_PB 47nF Rfs vs. SW Frequency 1.800 REA AVIN 1F CA resistor values are allowed. Do not use lower RFS values than recommendations as that may set the frequency too low and cause inductor saturation. When synchronizing multiple devices, use the highest recommended switching frequency of the devices. SWITCHING FREQUENCY (MHz) into a Pre-Bias voltage without the Pre-Bias Protection feature enabled can lead to device damage. When using the Pre-Bias feature, the device must be disabled using the ENABLE pin prior to PVIN falling out of regulation (<4.5V), otherwise damage may occur during shutdown. To disable the Pre-Bias feature pull the EN_PB pin directly to ground. Do not leave the EN_PB pin floating. See Typical Performance Characteristics for an example of Pre-Bias Protection. See Figure X for a typical schematic with Pre-Bias Protection enabled. RCLX RB PVIN RCLX Figure X. Pre-Bias Application Circuit 12V Frequency Synchronization The switching frequency of the EN2392QI can be phase-locked to an external clock source to move unwanted beat frequencies out of band. The internal switching clock of the EN2392QI can be phase locked to a clock signal applied to the S_IN pin. An activity detector recognizes the presence of an external clock signal and automatically phaselocks the internal oscillator to this external clock. Phase-lock will occur as long as the input clock frequency is in the range of 0.9MHz to 1.8MHz. The external clock frequency must be within 10% of the nominal switching frequency set by the RFS resistor. It is recommended to use a synchronized clock frequency close to the typical frequency recommendations in Table 1. A 3.01k resistor from FQADJ to ground is recommended for clock frequencies within 10% of 1MHz. When no clock is present, the device reverts to the free running frequency of the internal oscillator set by the RFS resistor. The efficiency performance of the EN2392QI for various PVIN/VOUT combinations can be optimized by adjusting the switching frequency. Table 1 shows recommended RFS values for various PVIN/VOUT combinations in order to optimize performance of the EN2392QI. Using higher RFS VOUT 3.3V 2.5V 1.8V 1.5V 1.2V 1.0V RFS 22k 10k 4.87k 3.01k 3.01k 3.01k Typical fsw 1.42 MHz 1.3 MHz 1.15 MHz 1.0 MHz 1.0 MHz 1.0 MHz Table 1: Recommended RFS Values. Soft-Start Operation Soft start is a means to ramp the output voltage gradually upon start-up. The output voltage rise time is controlled by the choice of soft-start capacitor, which is placed between the SS pin and the AGND pin. During start-up of the converter, the reference voltage to the error amplifier is linearly increased to its final level by an internal current source of approximately 10A. The soft-start time is measured from when VIN > VUVLOR and ENABLE pin voltage crosses its logic high threshold to when VOUT reaches its programmed value. The total softstart time can be calculated by: Soft Start Time (ms): TSS Css [nF] x 0.06 Typical soft-start time is approximately 2.8ms with SS capacitor value of 47nF. www.altera.com/enpirion Page 16 10107 June 2, 2015 Rev C EN2392QI POK Operation The POK signal is an open drain signal (requires a pull up resistor to AVIN or similar voltage) from the converter indicating the output voltage is within the specified range. Typically, a 100k or lower resistance is used as the pull-up resistor. The POK signal will be logic high (AVIN) when the output voltage is above 90% of the programmed voltage level. If the output voltage is below this point, the POK signal will be a logic low. The POK signal can be used to sequence down-stream converters by tying to their enable pins. Over Current Protection 4.5V to 13.2V VOUT 3.3V 2.5V 1.8V 1.5V 1.2V 1.0V RCLX 31.6k 34.8k 35.7k 34.8k 39.2k 40.2k AVIN Under-Voltage Lock-Out (UVLO) Internal circuits ensure that the converter will not start switching until the AVIN input voltage is above the specified minimum voltage. Hysteresis, input de-glitch and output leading edge blanking ensures high noise immunity and prevents false UVLO triggers. Master / Slave (Parallel) Operation: RFS 22k 10k 4.87k 3.01k 3.01k 3.01k Table 2: Recommended RCLX Values Thermal Overload Protection Thermal shutdown circuit will disable device operation when the junction temperature exceeds approximately 150C. The device will go through a soft-shutdown and allow the output to discharge in a controlled manner. This prevents excessive Parallel Current Share Breakdown INDIVIDUAL OUTPUT CURRENT (A) The current limit function is achieved by sensing the current flowing through a high-side sense PFET. If the current exceeds the OCP threshold, the switching cycle is terminated and an OCP counter is incremented. If the counter value reaches 32 OCP cycles, the device will shut down as described below. If there are 8 consecutive cycles that do not exceed the OCP threshold, the counter will reset. Once the OCP counter has reached 32 cycles, the MOSFET switches will tristate and the soft start capacitor will be discharged. After approximately 32ms the device will attempt a restart. If the OCP condition persists, the device will enter a hiccup mode until the OCP condition is removed. The OCP trip point depends on PVIN, VOUT, RCLX, RFS and is meant to protect the device from damage. OCP is not an adjustable threshold. Follow Table 2 for recommended RCLX and RFS values to set the current limit above 9A under normal operating conditions. Not following Table 2 may result in current limit being too low or too high. Note: Do not leave RCLX pin floating. PVIN output ringing in the event of a thermal fault condition. After a thermal shutdown event, when the junction temperature drops by approximately 35C, the converter will re-start with a normal softstart. 10 9 8 MASTER 7 SLAVE 6 IDEAL 5 4 CONDITIONS EN2390QI VIN = 12V VOUT = 1.2V 3 2 1 0 2 4 6 8 10 12 14 TOTAL OUTPUT CURRENT (A) 16 Figure 10. Parallel Current Matching Up to four EN2392QI devices may be connected in a Master/Slave configuration to handle larger load currents. The maximum output current for each parallel device will need to be de-rated by 20 percent so that no devices will over current due to current mis-match. The Master device's switching clock may be phase-locked to an external clock source via the S_IN pin or left open and use its default switching frequency. The device is placed in Master mode by pulling the M/S pin low or in Slave mode by pulling M/S pin high. Note that the M/S pin is also pulled low for standalone mode. In Master mode, the internal PWM signal is output on the S_OUT pin. This PWM signal from the Master is fed to the Slave device at its S_IN input. The Slave device acts like an extension of the power FETs in the Master. The inductor in the Slave prevents crow-bar currents from Master to Slave due to timing delays. Parallel operation in dual supply mode is shown in Figure 11. Single supply mode operation may also be implemented similarly. Note that only critical components are shown. The red www.altera.com/enpirion Page 17 10107 June 2, 2015 Rev C EN2392QI text and red lines indicate the important parallel operation connections and care should be taken in layout to ensure low impedance between those paths. The parallel current matching is illustrated in Figure 10. Note 2: The Master and Slave VOUTs should be connected with very low impedance as shown by the double red line connections in parallel. Note 1: The Master and Slave VINs should be connected with very low impedance as shown by the double red line connections in parallel. VIN ENA 22F 1206 AVIN AVIN 2x 47F 1206 EN2392QI (MASTER) RA CA VFB SS 47nF VOUT VOUT PVIN R1 M/S PGND PGND S_OUT AGND RB FQADJ S_IN VOUT PVIN AVIN 22F 1206 ENA 2x 47F 1206 EN2392QI (SLAVE) AVIN VFB M/S open SS PGND PGND FQADJ AGND 47nF Slave #1 Note 4: Up to 3 Slaves may be used in parallel with the Master Note 3: The Master and Slave PGNDs should be connected with very low impedance as shown by the double red line connections in parallel. Figure 11. Parallel Operation Illustration www.altera.com/enpirion Page 18 10107 June 2, 2015 Rev C EN2392QI Application Information Output Voltage Programming and Loop Compensation The EN2392QI uses a Type IV Voltage Mode compensation network. Type IV Voltage Mode control is a proprietary Altera Enpirion control scheme that maximizes control loop bandwidth to deliver excellent load transient responses and maintain output regulation with pin point accuracy. For ease of use, most of this network has been customized and is integrated within the device package. The EN2392QI output voltage is programmed using a simple resistor divider network (RA and RB). The feedback voltage at VFB is nominally 0.6V. RA is predetermined based on Table 5 and RB can be calculated based on Figure 12. The values recommended for COUT, CA, RCA and REA make up the external compensation of the EN2392QI. It will vary with each PVIN and VOUT combination to optimize on performance. The EN2392QI solution can be optimized for either smallest size or highest performance. Please see Table 5 for a list of recommended RA, CA, RCA, REA and COUT values for each solution. Since VFB is a sensitive node, do not touch the VFB node while the device is in operation as doing so may introduce parasitic capacitance into the control loop that causes the device to behave abnormally and damage may occur. VOUT VOUT COUT EAIN RA CA REA RCA VFB VFB = 0.6V PGND RB = EN2392QI VFB x RA VOUT - VFB Figure 12: VOUT Resistor Divider & Compensation Components. See Table 5 for details. should be used as input capacitors for this converter. The dielectric must be X5R or X7R rated. Y5V or equivalent dielectric formulations must not be used as these lose too much capacitance with frequency, temperature and bias voltage. In some applications, lower value capacitors are needed in parallel with the larger, capacitors in order to provide high frequency decoupling. Distance from the input power source to the input of the device creates parasitic inductance which can increase input ripple during startup or in steady state operation. Be sure the input is properly filtered with additional bulk capacitance so that the input AC ripple on PVIN is less than 1V peak-to-peak. Placing capacitors in parallel reduces the impedance and will result in lower ripple voltage. Table 2 contains a list of recommended input capacitors. Recommended Input Capacitors Description MFG P/N 22F, 16V, X5R, 10%, 1206 Murata GRM31CR61C226ME15 22F, 16V, X5R, 20%, 1206 Taiyo Yuden EMK316ABJ226ML- T Table 2: Recommended Input Capacitors Output Capacitor Selection As seen from Table 5, the EN2392QI has been optimized for use with one 100F/1206 plus two 47F/1206 output capacitors for best performance. For smallest solution size, various combinations of output capacitance may be used. See Table 5 for details. Low ESR ceramic capacitors are required with X5R or X7R rated dielectric formulation. Y5V or equivalent dielectric formulations must not be used as these lose too much capacitance with frequency, temperature and bias voltage. Table 4 contains a list of recommended output capacitors. Extra bulk capacitors may be used to improve load transient response at the load. The maximum output capacitance allowed on the EN2392QI depends on the output voltage. Table 3 shows the maximum output capacitance based on output voltage. The maximum output capacitance includes all capacitors connected from the output power plain to ground. Input Capacitor Selection The EN2392QI requires two 22F/1206 input capacitors. Low-cost, low-ESR ceramic capacitors www.altera.com/enpirion Page 19 10107 June 2, 2015 Rev C EN2392QI 1 VOUT RFS COUT_MAX Snubber 3.3V 22k 800F 4.7 + 680pF 2.5V 10k 1200F 4.7 + 680pF 1.8V 4.87k 1600F 4.7 + 680pF 1.5V 3.01k 1800F 4.7 + 680pF 1.2V 3.01k 2000F 4.7 + 680pF 1.0V 3.01k 2200F 4.7 + 680pF Table 3: Maximum Output Capacitance If the maximum output capacitance in the application exceeds 50% of the COUT_MAX value in Table 3, then a "snubber" circuit is required (See Figure 1). The "snubber" circuit is a series resistor and capacitor from the NC(SW) pin to PGND. The "snubber" values are optimized for the EN2392QI and should be followed to within 10% of the recommendations. Due to the added power dissipation, using the "snubber" will decrease the converter efficiency by around 1 percent. It is recommended to use at least a 1/4W resistor at 1206 case size or greater due to power dissipation. The capacitor should be at least 0603 case size. Z Total = 1 1 1 + + ... + Z1 Z 2 Zn Recommended Output Capacitors Description 47F, 6.3V, X5R, 20%, 1206 47F, 10V, X5R, 20%, 1206 22F, 10V, X5R, 20%, 0805 22F, 10V, X5R, 20%, 0805 100F, 6.3V, X5R, 20%, 1206 MFG P/N Murata GRM31CR60J476ME19L Taiyo Yuden LMK316BJ476ML- T Panasonic ECJ-2FB1A226M Taiyo Yuden LMK212BJ226MG- T Murata GRM31CR60J107ME39L Taiyo Yuden JMK316BJ107ML-T Table 4: Recommended Output Capacitors Since additional bulk capacitance changes the LC double pole of the Voltage Mode Control architecture, be sure to have at least 4m of separation between the feedback sense point and the additional bulk capacitors. Be sure to follow the Best Performance external compensation recommendations in Table 5. The output capacitance can also influence the output ripple. Output ripple voltage is determined by the aggregate output capacitor impedance. Capacitor impedance, denoted as Z, is comprised of capacitive reactance, effective series resistance, ESR, and effective series inductance, ESL reactance. Placing output capacitors in parallel reduces the impedance and will hence result in lower ripple voltage. www.altera.com/enpirion Page 20 10107 June 2, 2015 Rev C EN2392QI Best Performance Smallest Solution Size CIN = 2x22F/1206 CIN = 2x22F/1206 V OUT 1.8V, COUT = 2x47F/0805 1.8V < V OUT 3.3V, COUT = 2x47F/1206 COUT = 100F/1206 + 2x47F/1206 RA = 200 k PVIN (V) 13.2V 12V 10V 8V 6.6V 5V RA = 75k RCA REA (k (k) ) 8.2 Open VOUT (V) CA (pF) RCA (k) REA (k) Ripple (m V) Deviation (m V) 0.9V 15 18 0 5.83 44 0.9V CA (pF ) 18 1.2V 15 22 0 7.22 48 1.2V 18 8.2 Open 21 104 1.5V 18 22 0 8.63 38 1.5V 18 8.2 Open 27 110 1.8V 15 22 0 10.8 50 1.8V 18 8.2 Open 35 120 2.5V 27 5.1 33 14.6 72 2.5V 15 8.2 Open 54 150 3.3V 22 8.2 33 26.1 76 3.3V 10 8.2 Open 81 215 0.9V 27 18 0 5.21 40 0.9V 27 5.1 Open 15 96 1.2V 22 22 0 6.7 36 1.2V 27 5.1 Open 21 104 1.5V 18 22 0 8.98 44 1.5V 27 5.1 Open 27 112 1.8V 18 22 0 10 50 1.8V 27 5.1 Open 34 130 2.5V 27 5.1 33 12.6 76 2.5V 22 5.1 Open 52 162 3.3V 22 8.2 33 23.6 72 3.3V 15 5.1 Open 77 221 PVIN (V) 13.2V 12V VOU T (V) Rippl e (m V) 15 Deviatio n (m V) 93 0.9V 27 18 0 5.01 44 0.9V 56 2 Open 15 99 1.2V 22 22 0 6.28 40 1.2V 56 2 Open 20 107 1.5V 18 22 0 8.57 54 1.5V 39 2 Open 26 122 10V 1.8V 18 22 0 9.44 60 1.8V 39 2 Open 33 126 2.5V 33 5.1 33 11 64 2.5V 33 2 Open 50 169 3.3V 27 8.2 33 21.6 68 3.3V 22 2 Open 71 241 0.9V 27 18 0 4.9 44 0.9V 100 0 Open 15 108 1.2V 22 22 0 5.82 48 1.2V 100 0 Open 20 113 1.5V 22 22 0 7.48 56 1.5V 82 0 Open 25 122 1.8V 22 22 0 8.01 54 1.8V 68 0 Open 31 136 2.5V 33 5.1 33 10.7 76 2.5V 47 0 Open 46 183 3.3V 27 8.2 33 20.5 84 3.3V 33 0 Open 62 253 0.9V 33 18 0 4.58 46 0.9V 100 0 Open 14 121 1.2V 27 22 0 5.28 54 1.2V 100 0 Open 19 128 1.5V 27 22 0 6.44 54 1.5V 100 0 Open 24 138 1.8V 22 22 0 7.2 58 1.8V 100 0 Open 29 149 2.5V 3.3V 0.9V 33 33 39 5.1 8.2 18 33 33 0 11.4 18.4 4.1 84 96 54 2.5V 3.3V 0.9V 68 47 100 0 0 0 Open Open Open 41 53 13 188 239 152 1.2V 33 22 0 5.1 62 1.2V 100 0 Open 18 161 8V 6.6V 5V 1.5V 27 22 0 6.2 66 1.5V 100 0 Open 22 177 1.8V 27 22 0 7.02 68 1.8V 100 0 Open 25 183 2.5V 39 5.1 33 9.84 104 2.5V 100 0 Open 33 216 Table 5: RA, CA, RCA and REA Values for Various PVIN/VOUT Combinations: Best Performance vs. Smallest Solution Size. Use the equations in Figure 12 to calculate RB. Output Ripple is measured at no load and Nominal Deviation is for a 9A load transient step in one direction. For a voltage in between the specified output voltages, choose compensation values of the lower output voltage setting. www.altera.com/enpirion Page 21 10107 June 2, 2015 Rev C EN2392QI Thermal Considerations Thermal considerations are important power supply design facts that cannot be avoided in the real world. Whenever there are power losses in a system, the heat that is generated by the power dissipation needs to be accounted for. The Altera Enpirion PowerSoC helps alleviate some of those concerns. The Altera Enpirion EN2392QI DC-DC converter is packaged in a 10x11x3mm 76-pin QFN package. The QFN package is constructed with copper lead frames that have exposed thermal pads. The exposed thermal pad on the package should be soldered directly on to a copper ground pad on the printed circuit board (PCB) to act as a heat sink. The recommended maximum junction temperature for continuous operation is 125C. Continuous operation above 125C may reduce long-term reliability. The device has a thermal overload protection circuit designed to turn off the device at an approximate junction temperature value of 150C. The following example and calculations illustrate the thermal performance of the EN2392QI. Example: VIN = 12V VOUT = 1.2V PIN 10.8W / 0.8 13.17W The power dissipation (PD ) is the power loss in the system and can be calculated by subtracting the output power from the input power. PD = PIN - POUT 13.17W - 10.8W 2.37W With the power dissipation known, the temperature rise in the device may be estimated based on the theta JA value (JA). The JA parameter estimates how much the temperature will rise in the device for every watt of power dissipation. The EN2392QI has a JA value of 15 C/W without airflow. Determine the change in temperature (T) based on PD and JA. T = PD x JA T 2.37W x 15C/W = 35.56C 36C The junction temperature (T J ) of the device is approximately the ambient temperature (T A) plus the change in temperature. We assume the initial ambient temperature to be 25C. T J 25C + 36C 61C First calculate the output power. POUT = 1.2V x 9A = 10.8W Next, determine the input power based on the efficiency () shown in Figure 13. Efficiency vs. Output Current 100 80 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V VOUT = 1.0V The maximum operating junction temperature (T JMAX) of the device is 125C, so the device can operate at a higher ambient temperature. The maximum ambient temperature (T AMAX) allowed can be calculated. T AMAX = T JMAX - PD x JA 125C - 36C 89C The maximum ambient temperature the device can reach is 89C given the input and output conditions. Note that the efficiency will be slightly lower at higher temperatures and this calculation is an estimate. Check De-rating Curves for guaranteed maximum output current over temperature. 90 EFFICIENCY (%) PIN = POUT / T J = T A + T IOUT = 9A 10 = POUT / PIN = 82% = 0.82 CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply 0 0 1 2 3 4 5 6 OUTPUT CURRENT (A) 7 8 9 Figure 13: Efficiency vs. Output Current For VIN = 12V, VOUT = 1.2V at 9A, 82% www.altera.com/enpirion Page 22 10107 June 2, 2015 Rev C EN2392QI Engineering Schematic Figure 14: Typical Engineering Schematic www.altera.com/enpirion Page 23 10107 June 2, 2015 Rev C EN2392QI Layout Recommendation Figure 15: Critical Component Layout for Minimum Footprint (Top Layer). See Figure 14 for schematic. This layout only shows the critical components and top layer traces for minimum footprint in single-supply, master mode. Alternate circuit configurations & other low-power pins need to be connected and routed according to customer application. Please see the Gerber files at www.altera.com/enpirion for details on all layers. Recommendation 1: Input and output filter capacitors should be placed on the same side of the PCB, and as close to the EN2392QI package as possible. They should be connected to the device with very short and wide traces. Do not use thermal reliefs or spokes when connecting the capacitor pads to the respective nodes. The +V and GND traces between the capacitors and the EN2392QI should be as close to each other as possible so that the gap between the two nodes is minimized, even under the capacitors. Recommendation 2: The PGND connections for the input and output capacitors on layer 1 need to have a slit between them in order to provide some separation between input and output current loops. Recommendation 3: The system ground plane should be the first layer immediately below the surface layer. This ground plane should be continuous and un-interrupted below the converter and the input/output capacitors. Recommendation 4: The thermal pad underneath the component must be connected to the system ground plane through as many vias as possible. The drill diameter of the vias should be 0.33mm, and the vias must have at least 1 oz. copper plating on the inside wall, making the finished hole size around 0.20-0.26mm. Do not use thermal reliefs or spokes to connect the vias to the ground plane. This connection provides the path for heat dissipation from the converter. Recommendation 5: Multiple small vias (the same size as the thermal vias discussed in recommendation 4) should be used to connect ground terminal of the input capacitor and output capacitors to the system ground plane. It is preferred to put these vias along the edge of the GND copper closest to the +V copper. These vias connect the input/output filter capacitors to the GND plane, and help reduce parasitic inductances in the input and output current loops. If vias cannot be placed under the capacitors, then place them on both sides of the slit in the top layer PGND copper. Recommendation 6: AVIN is the power supply for the small-signal control circuits. AVINO powers AVIN in single supply mode. AVIN and AVINO should have a decoupling capacitor close to each of their pins. Refer to Figure 15. Recommendation 7: The layer 1 metal under the device must not be more than shown in Figure13. Refer to the section regarding Exposed Metal on Bottom of Package. As with any switch-mode DC/DC converter, try not to run sensitive signal or control lines underneath the converter package on other layers. Recommendation 8: The VOUT sense point should be just after the last output filter capacitor. Keep the sense trace short in order to avoid noise coupling into the node. Contact Altera MySupport for any remote sensing applications. Recommendation 9: Keep RA, CA, RB, and RCA close to the VFB pin (Refer to Figure 15). The VFB pin is a high-impedance, sensitive node. Keep the trace to this pin as short as possible. Whenever possible, connect RB directly to the AGND instead of going through the GND plane. Recommendation 10: Follow all the layout recommendations as close as possible to optimize performance. Altera provides schematic and layout reviews for all customer designs. Contact Altera MySupport for detailed support (www.altera.com/mysupport). www.altera.com/enpirion Page 24 10107 June 2, 2015 Rev C EN2392QI Design Considerations for Lead-Frame Based Modules Exposed Metal on Bottom of Package Lead-frames offer many advantages in thermal performance, in reduced electrical lead resistance, and in overall foot print. However, they do require some special considerations. In the assembly process lead frame construction requires that, for mechanical support, some of the lead-frame cantilevers be exposed at the point where wire-bond or internal passives are attached. This results in several small pads being exposed on the bottom of the package as shown in Figure 16. Only the thermal pad and the perimeter pads are to be mechanically or electrically connected to the PC board. The PCB top layer under the EN2392QI should be clear of any metal (copper pours, traces, or vias) except for the thermal pad. The "shaded-out" area in Figure 16 represents the area that should be clear of any metal on the top layer of the PCB. Any layer 1 metal under the shaded-out area runs the risk of undesirable shorted connections even if it is covered by soldermask. The solder stencil aperture should be smaller than the PCB ground pad. This will prevent excess solder from causing bridging between adjacent pins or other exposed metal under the package. Please consult the EN2392QI QFN Package Soldering Guidelines for more details and recommendations. Figure 16: Lead-Frame exposed metal (Bottom View) Shaded area highlights exposed metal that is not to be mechanically or electrically connected to the PCB. www.altera.com/enpirion Page 25 10107 June 2, 2015 Rev C EN2392QI Recommended PCB Footprint Figure 17: EN2392QI PCB Footprint (Top View) The solder stencil aperture for the thermal pad (shown in blue) is based on Altera's manufacturing recommendations. www.altera.com/enpirion Page 26 10107 June 2, 2015 Rev C EN2392QI Package and Mechanical Figure 18: EN2392QI Package Dimensions (Bottom View) Packing and Marking Information: www.altera.com/support/reliability/packing/rel-packing-and-marking.html Contact Information Altera Corporation 101 Innovation Drive San Jose, CA 95134 Phone: 408-544-7000 www.altera.com (c) 2013 Altera Corporation--Confidential. All rights reserved. ALTERA, ARRIA, CYCLONE, ENPIRION, HARDCOPY, MAX, MEGACORE, NIOS, QUARTUS and STRATIX words and logos are trademarks of Altera Corporation and registered in the U.S. Patent and Trademark Office and in other countries. All other words and logos identified as trademarks or service marks are the property of their respective holders as described at www.altera.com/common/legal.html. Altera warrants performance of its semiconductor products to current specifications in accordance with Altera's standard warranty, but reserves the right to make changes to any products and services at any time without notice. Altera assumes no responsibility or liability arising out of the application or use of any information, product, or service described herein except as expressly agreed to in writing by Altera. Altera customers are advised to obtain the latest version of device specifications before relying on any published information and before placing orders for products or services. www.altera.com/enpirion Page 27 10107 June 2, 2015 Rev C