U2893B Modulation PLL for GSM, DCS and PCS Systems Description The U2893B is a monolithic integrated circuit manufactured using Atmel Wireless & Microcontrollers' advanced silicon bipolar UHF5S technology. The device integrates a mixer, an I/Q modulator, a phase-frequency detector (PFD) with two synchronous programmable dividers, and a charge pump. The U2893B is designed for cellular phones such as GSM900, DCS1800, and PCS1900, applying a transmitter architecture at which the VCO operates at the TX output frequency. No duplexer is needed since the out-of-band noise is very low. The U2893B exhibits low power consumption. Broadband operation provides high flexibility for multi-band frequency mappings. The IC is available in a shrinked small-outline 28-pin package (SSO28). The U2894B offers the same functionality with divider ratios of 2 and 1 (direct PFD access). Features Benefits Supply-voltage range 2.7 V to 5.5 V Novel TX architecture saves filter costs Current consumption 50 mA Extended battery operating time without duplexer Power-down functions Less board space (few external components) High-speed PFD and charge pump (CP) VCO control without voltage doubler Small CP saturation voltages (0.5/0.6 V) Small SSO28 package Programmable dividers and CP polarity Electrostatic sensitive device. Observe precautions for handling. One device for all GSM bands Low-current standby mode Block Diagram I NI 1 2 MDLO Q NQ PUMIX PU MIXO MIXLO 3 28 27 12 NMDO ND NND RD NRD 25 20 Voltage reference 90 MDO 19 22 5 6 23 Mixer NRF + I/Q modulator 8 16 17 N 1 divider MUX 13 14 PFD 9 Charge pump R 1 divider 7 21 MC RF 15 Mode control 26 4 18 24 GND 11 CPC VSP CPO VS1 VS2 VS3 10 GNDP 12494 Figure 1. Block diagram Rev. A6, 04-Oct-00 1 (16) U2893B Ordering Information Extended Type Number Package Remarks U2893B-MFS SSO28 Tube U2893B-MFSG3 SSO28 Taped and reeled Pin Description I 1 28 Q NI 2 27 NQ MDLO 3 26 VS3 GND 4 25 MIXO MDO 5 24 GND NMDO 6 23 NRF VS1 7 22 RF VSP 8 21 CPO 9 20 MIXLO 19 GNDP 10 CPC VS2 18 11 PU GND PUMIX 12 17 NND 13 16 ND NRD 14 15 MC RD 12495 Figure 2. Pinning AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAA AAAAAAAA AAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAA AAAA AAAAAAAAAAA AAA AAAA AAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAA AAA AAAA AAAAAAAAAAA AAAAAAAAAAAAAAAAAA Pin Symbol 1 I 2 NI 3 MDLO 4 1) 1) 2) 3) 2 (16) Function In-phase baseband input Complementary to I GND I/Q-modulator LO input Negative supply 5 MDO 6 NMDO I/Q-modulator output Complementary to MDO 7 VS1 3) Positive supply (I/Q MOD) 8 VSP 9 CPO Pos. supply charge pump Charge-pump output 2) 10 GNDP Neg. supply charge pump 11 CPC 12 PUMIX 13 RD 14 NRD Complementary to RD 15 MC Mode control 16 ND N-divider input 17 NND Charge-pump current control (input) Power-up, mixer only R-divider input 1) 18 GND 19 PU 20 MIXLO Complementary to ND Negative supply Power-up, whole chip except mixer 3) 21 VS2 22 RF 23 NRF Mixer LO input Positive supply (MISC.) Mixer RF-input 1) 24 GND 25 MIXO 26 VS3 3) 27 NQ 28 Q Complementary to RF Negative supply Mixer output Positive supply (mixer) Complementary to Q Quad.-phase baseband input All GND pins must be connected to GND potential. No DC voltage between GND pins! Max. voltage between GNDP and GND pins 200 mV The maximum permissible voltage difference between pins VS1, VS2 and VS3 is 200 mV. Rev. A6, 04-Oct-00 U2893B Absolute Maximum Ratings AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAA Parameters Symbol Value Unit Supply voltage VS1, VS2, VS3 VVS# VVSP V Supply voltage charge pump VSP VVSP 5.5 V Voltage at any input VVi# -0.5 VVS +0.5 5.5 V Current at any input / output pin except CPC | II# | | IO# | 2 mA CPC output currents | ICPC | 5 mA Ambient temperature Tamb -20 to +85 C Storage temperature Tstg -40 to +125 C Operating Range AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAA AAAAAAAAA AAAAAAAAA AAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA Parameters Supply voltage Symbol Value Unit VVS#, VVSP 2.7 to 5.5 V Tamb -20 to +85 C Ambient temperature Thermal Resistance AAAAAAAAAAAA AAAAAAAAA AAAAAAAAA AAAAA AAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAA Parameters Symbol Value Unit RthJA 130 K/W Junction ambient SSO28 Electrical Characteristics Tamb = 25C, VS = 2.7 to 5.5 V AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAA AAAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAA AAAAA AAAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAA AAAAA AAAA AAA AAAA AAAAAAAA AAAAAAAAAAAAAA AAAAA AAAAAAAAAAAAAAAAA AAAAA AAAAAAAAA AAAAAAA AAAAAAA AAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAA AAAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA Parameters Test Conditions / Pin Symbol Min. VVS# VVSP Typ. Max. Unit 2.7 5.5 V VVS# - 0.3 5.5 V 23 mA 20 A 22 mA 20 A 17 mA 30 A 1.8 mA 20 A DC supply Supply voltages VS# VVS1 = VVS2 = VVS3 Supply voltage VSP Supply pp y current IVS1 Supply pp y current IVS2 Supply pp y current IVS3 Supply current IVSP 1) Active (VPU = VS) IVS1A Standby (VPU = 0) IVS1Y Active (VPU = VS) IVS2A Standby (VPU = 0) IVS2Y Active (VPUMIX = VS) IVS3A Standby (VPUMIX = 0) IVS3Y Active (VPU = VS, CPC open) IVSPA Standby (VPU = 0) IVSPY 18 17 13 1.4 N & R divider inputs ND, NND & RD, NRD N:1 divider frequency 50- source fND 100 600 MHz R:1 divider frequency 50- source fRD 100 600 MHz Input impedance Active & standby ZRD, ZND 1 k 2 pF - Input sensitivity 50- source VRD, VND 20 200 mVrms 1) Mean value, measured with FND = 151 MHz, FRD = 150 MHz, current vs. time, figure 3. Rev. A6, 04-Oct-00 3 (16) U2893B Electrical Characteristics (continued) Tamb = 25C, VS = 2.7 to 5.5 V AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAA AAAAAAAAAA AAAAAAAA AAAAAAA AAAAAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAAA AAAAAAAA AAAAAAAAAAAAAA AAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAA AAAAAAAA AAAAAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAA AAAAAAAA AAAAAAAAAAAAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA Parameters Test Conditions / Pin Symbol Min. 15 Typ. Max. Unit 120 MHz 300 MHz VS1/2 + 0.1 V 1 MHz Phase-frequency detector (PFD) PFD operation fND = 240 MHz, N = 2 fRD = 600 MHz, R = 5 fPFD Frequency comparison only 3) fND = 600 MHz, N = 5 fRD = 600 MHz, R = 2 fFD I/Q modulator baseband inputs I, NI & Q, NQ DC voltage MD_IQ AC voltage 4) Referred to GND VI, VNI, VQ, VNQ 1.35 VS1/2 Frequency range fIO DC Referred to GND ACI, ACNI, ACQ, ACNQ 200 mVpp Differential (preferres) ACDI, ACDQ 400 mVpp I/Q modulator LO input MDLO MDLO Frequency range fMDLO Input impedance Active & standby ZMDLO Input level 50- source PMDLO 50 350 MHz 250 -11 -8 -5 dBm I/Q modulator outputs MDO, NMDO DC current VMDO, VNMDO = VS IMDO, INMDO Voltage compliance VMDO, VNMDO = VC VCMDO, VC- MDO output level (differential) 500 to VS 5) 2.4 mA VS - 0.7 5.5 V PMDO 120 150 mVrms CSMDO -32 -35 dBc SSMDO -35 -40 dBc NMDO Carrier suppression 5) Sideband suppression IF spurious Noise 5) 5) 5) fLO 3 fmod SPMDO @ 400 kHz off carrier NMDO Frequency range -50 -45 dBc -115 dBc/Hz fMDO 50 350 MHz -23 -17 dBm -40 dBm Mixer (900 MHz) RF input level 900 MHz P9RF LO-spurious at RF/NRF port @ P9MIXLO = -10 dBm @ P9RF = -15 dBm SP9RF MIXLO input level 0.05 to 2.1 GHz P9MIXLO -22 -12 dBm MIXO (100- load) Frequency range fMIXO 50 350 MHz Output level 6) Carrier suppression 3) 4) 5) 6) 4 (16) @ P9MIXLO = -15 dBm P9MIXO @ P9MIXLO = -15 dBm CS9MIXO 70 mVrms -20 dBc PFD can be used as a frequency comparator until 300 MHz for loop acquisition Single-ended operation (complementary baseband input is AC-grounded) leads to reduced linearity (degrading suppression of odd harmonics) With typical drive levels at MDLO- & I/Q-inputs -1 dB compression point (CP-1) Rev. A6, 04-Oct-00 U2893B Electrical Characteristics (continued) Tamb = 25C, VS = 2.7 to 5.5 V AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAA AAAAAAAAAAA AAAAAAAA AAAAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAA AAAA AAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAA AAAAAAA AAAAAAA AAAAAAAA AAAA AAAAAAAAAAAAAAA AAAAAAAAAAA AAAAAAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAA AAAAAAAAAAA AAAAAAAA AAAA AAAAAAAA AAAAAA AAAAAAA AAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAA AAAAAAAAAAA AAAAAAAA AAAAAA AAAA AAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA AAAAAAAA AAAAAAAAA AAAAAA AAAA AAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAA Parameters Test Conditions / Pin Symbol Min. -23 Typ. Max. Unit -17 dBm -40 dBm -12 dBm Mixer (1900 MHz) RF input level 0.5 to 2 GHz P19RF LO-spurious at RF/NRF ports MIXLO input level @ P19MIXLO = -10 dBm @ P19RF = -15 dBm 0.05 to 2.1 GHz SP19RF P19MIXLO @ P19MIXLO = -17 dBm P19MIXO @ P19MIXLO = -17 dBm CS19MIXO -20 -22 MIXO (100 load) Output level 6) Carrier suppression Charge-pump output CPO (VVSP = 5 V, VCPO = 2.5 V) Pump-current p ppulse CPC open for DC RCPC = 2.2 k RCPC = 680 7) 7) TK pump current Mismatch source / sink current Sensivity to VSP (ICPOSI - ICPOSO)/ICPOSI ICPOSO = Isourc ICPOSI = Isink I | CPO | | VSP | I CPO VSP VCPO voltage range 55 mVrms dBc | ICPO | 0.7 1 1.3 mA | ICPO 2 | 1.4 2 2.6 mA | ICPO_4 | 3 4 5 mA Tk_| ICPC | 15 %/100K MICPO 0.1 - SICPO 0.1 - VVSP -0.6 V VCPO 0.5 CCPC 500 pF | ICPCK | 1.6 mA Charge-pump control input CPC Compensation capacitor Short-circuit current 8) CPC grounded Mode control Sink current VMC = VS IMC A 60 Power-up input PU (power-up for all functions, except mixer) Settling time High level Output power within 10% of steady state values Active VPUH Low level Standby VPUL High-level current Active, VPUH = 2.7 V IPUH Low-level current Standby, VPUL = 0.4 V IPUL 10 s 2.4 VS2 V 0 0.4 V 0.26 mA 20 A 10 s SPU 5 -1 Power-up input PUMIX (power-up for mixer only) Settling time High level Output power within 10% of steady state values Active VPUMIXH 2.4 VS2 V Low level Standby VPUMIXL 0 0.4 V High-level current Active, VPUMIXH = 2.7 V IPUMIXH 0.26 mA Low-level current Standby, VPUMIXL = 0.4 V IPUMIXL 20 A 6) 7) tsetl 5 -1 8) - 1 dB compression point (CP - 1) See figure 7 RCPC: external resistor to ground (GND) for charge-pump current control Rev. A6, 04-Oct-00 5 (16) U2893B Supply Current of the Charge Pump IVSP vs. Time Initial Charge-Pump Current after Power-Up Due to the pulsed operation of the charge pump, the current into the charge-pump supply Pin VSP is not constant. Depending on I (see figure 7) and the phase difference at the phase detector inputs, the current IVSP over time varies. Basically, the total current is the sum of the quiescent current, the charge-/discharge current, and - after each phase comparison cycle - a current spike (see figure 3). Due to stability reasons, the reference current generator for the charge pump needs an external capacitor (>500 pF from CPC to GND). After power-up, only the on-chip generated current I = ICPCK is available for charging the external capacitor. Due to the charge pump's architecture, the charge-pump current will be 2 I = 2 ICPCK until the voltage on CPC has reached the reference voltage (1.1 V). The following figures illustrate this behavior. ICPCK x RCPC Up VCPC Down VRef 5I IVSP 3I t1 I t0 t2 t t 2x ICPCK 2I ICPO ICPC t -2I 14552 I Figure 3. Supply current of the charge pump = f(t) Internal current, I, |ICPC| and ICPC vs. RCPC t t1 14561 RCPC I |ICPCO| ICPC CPC open 0.5 mA 1 mA 0 2.2 k 1.0 mA 2 mA -0.5 mA 680 2.0 mA 4 mA -1.5 mA (typical values) Time t1 can be calculated as t1 (1.1 V CCPC)/ICPCK e.g., CCPC = 1 nF, ICPCK = 2.7 mA (>1.6 mA) t1 0.4 s. Time t2 can be calculated as t2 (RCPC/2200 ) CCPC e.g., CCPC = 1 nF, RCPC = 2200 (Pin CPC open) t2 1.1 s Figure 4. The behavior of |ICPO| after power-up can be very advantageous for a fast settling of the loop. By using larger capacitors (>1 nF), an even longer period with maximum charge-pump current is possible. Ramp-up time for the internal band gap reference is about 1 s. This time has to be added to the times calculated for the charge-pump reference. 6 (16) Rev. A6, 04-Oct-00 U2893B Mode Selection The device can be programmed to different modes via an external resistor RMODE (including short, open) connected between Pin MC and VS2. The mode selection controls the N-, R-divider ratios, and the polarity of the charge-pump current. Mode Selection N-Divider Application fN < fR 1) fN > fR 1) 5:1 Sink Source GSM 2:1 5:1 Source Sink PCS 10 k (5%) 2:1 6:1 Source Sink DCS 4 36 k (5%) 3:1 6:1 Source Sink GSM 5 (>1 M) 3:1 6:1 Sink Source GSM Mode Resistance between Pin MC and Pin VS2 1 0 (<50 ) 3:1 2 2.7 k (5%) 3 1) 2) CPO Current Polarity 2) R-Divider Frequencies referred to PFD input! Sink: current into Pin CPO. Source: current out from Pin CPO. Equivalent Circuits at the IC's Pins VS1 MDO NMDO VBias_MDLO 2230 2230 250 L,Q MDLO NI, NQ VRef_input VRef_MDLO VRef_output 30 pF GND Baseband input LO input Output 14553 Figure 5. I/Q modulator 1 k 1 k VBias_RF VBias_LO VS3 RF 890 890 NRF 1.6 k 1.6 k MIXLO VRef_RF 6.3 40 pF VRef_LO MIXO GND LO input Output 14554 Figure 6. Mixer Rev. A6, 04-Oct-00 7 (16) U2893B VS2 4 VSP 4 4 ICPCK /4 I CPC up Ref 1.1 V 2I down CPO Ref 2230 2 GND 2I 2 GNDP = Transistor with an emitter-area factor of "n" n 14555 Figure 7. Charge pump VS2 20 k ND/RD PU, PUMIX 2 k 2 k 30 k NND/NRD GND 14557 VRef_div Figure 9. Power-up GND 14556 Figure 8. Dividers VS2 N-divider Logic R-divider C (U) 2.5 pF @ 2 V C (U) is a non-linear junction capacitance MUX MC Figure 11. ESD-protection diodes 2x 60 A GND 14559 14898 Figure 10. Mode control 8 (16) Rev. A6, 04-Oct-00 U2893B Test Circuit Baseband input Baseband input <450 mVpp <450 mVpp VAC VAC VDC 1 28 2 27 1.35 V - VS1/2 +0.1 V Modulator LO input VDC 1.35 V - VS1/2 +0.1 V 3 26 VS 4 25 Mixer output 5 24 6 23 VS 7 22 Mixer input VSP 8 21 VS VDO 9 20 Mixer LO input PFD Pulse output 10 19 11 18 12 17 13 16 14 15 50 Modulator outputs 50 1 nF PFD input 50 PFD input 50 50 Power-up VS Bias voltage for charge-pump output: 0.5 V < VDO < VSP - 0.5 V 50 Mode control VS2 R1 R2 R3 13315 Figure 12. Test circuit Rev. A6, 04-Oct-00 9 (16) U2893B Application Hints Interfacing Mode Control For some baseband ICs it may be necessary to reduce the I/Q voltage swing so that it can be handled by the U2893B. In those cases, the following circuitry can be used. U2893B U2893B VS2 VS2 RMode R1 I R1 Baseband IC RMode1 I NI Q Q R1 NQ MC R2 NI RMode2 a) any single mode MC b) any 2 modes U2893B R2 NQ R1 U2893B U2893B VS2 VS2 12496 Figure 13. Interfacing the U2893B to I/Q baseband circuits RMode MC RMode MC Due to a possible current offset in the differential baseband inputs of the U2893B, the best values for the carrier suppression of the I/Q modulator can be achieved with voltage-driven I/NI-, and Q/NQ-inputs. A value of Rsource = R2/2 x RS 1.5 k should be realized. RS is the sum of R1 (above drawing) and the output resistance of the baseband IC. c) any mode & mode 5 36 k or 10 k d) mode 5 & mode 3 or mode 4 14560 Figure 15. Application examples for programming different modes Charge-Pump Current Programming GND CPC RCPC1 = 2.2 k RCPC2 = 1 k (incl. rds_on of FET) 1 nF RCPC1 RCPC2 `H' |I | = 4 mA CPO `L' |ICPO | = 2 mA 12497 Figure 14. Programming the charge-pump current 10 (16) Rev. A6, 04-Oct-00 U2893B Application Circuit for GSM900 (890 to 915 MHz) Baseband processor 200 27 nH LO (-10 dBm) 1171-1206 MHz 2x 12 pF 2.7 to 3.5 V 1 Dr 2 3 28 27 12 Dr 4.7 pF 25 20 Voltage reference 90 5 19 22 Mixer 6 47 nH 16 PFD 13 50 6 dB attn. 8 2.7 VCO to 3.5 V MQE550 N 1 divider MUX f_Ref Vrms = 55 mV 23 I/Q modulator 17 14 390 Charge pump to PA f_TX (880- 915 MHz) + 47 nH 1 k 50 9 3.3 nF R 1 divider 68 pF 390 7 (485 MHz) 21 15 Mode control 2.7 to 3.5 V 26 4 18 24 11 10 RMODE = 0 13316 Power-up, charge-pump control, and mode control must be connected according to the application used Figure 16. Application circuit Measurements Modulation-Loop Settling Time As valid for all PLL loops, the settling time depends on several factors. Figure 17 is an extraction from measurements performed in an arrangement like the application circuit. It shows that a loop settling time of a few s can be achieved. CPC: 1 k to GND CPC `open' Vertical: VCO tuning voltage 1 V/Div Horizontal: Time 1 s/Div Figure 17. Rev. A6, 04-Oct-00 11 (16) U2893B Modulation Spectrum & Phase Error Application for GSM900 Figure 18. Modulation spectrum Figure 19. Phase error 12 (16) Rev. A6, 04-Oct-00 U2893B Application for DCS1800 Figure 20. Modulation spectrum Figure 21. Phase error Rev. A6, 04-Oct-00 13 (16) U2893B Application for PCS1900 PCS 1900 USER TOL. Figure 22. Modulation spectrum PCS 1900 Figure 23. Phase error Complete transmitters (including PA) were measured. The test equipment was the R & S CMD55 performing standard approval tests. Typically, the spectrum @ 400 kHz off the center carrier frequency is approximately -65 dB attenuated (-60 dB according 14 (16) specificarion). The corresponding rms phase error is about 3. Dimensioning the loop-filters allows to optimize spectral-and phase error performance. Rev. A6, 04-Oct-00 U2893B Package Information Package SSO28 Dimensions in mm 5.7 5.3 4.5 4.3 9.10 9.01 1.30 0.15 0.15 0.05 0.25 0.65 6.6 6.3 8.45 28 15 technical drawings according to DIN specifications 13018 1 Rev. A6, 04-Oct-00 14 15 (16) U2893B Ozone Depleting Substances Policy Statement It is the policy of Atmel Germany GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances (ODSs). The Montreal Protocol (1987) and its London Amendments (1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban on these substances. Atmel Germany GmbH has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2. Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency (EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively. Atmel Germany GmbH can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. 6. We reserve the right to make changes to improve technical design and may do so without further notice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use Atmel Wireless & Microcontrollers products for any unintended or unauthorized application, the buyer shall indemnify Atmel Wireless & Microcontrollers against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. Data sheets can also be retrieved from the Internet: http://www.atmel-wm.com Atmel Germany GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany Telephone: 49 (0)7131 67 2594, Fax number: 49 (0)7131 67 2423 16 (16) Rev. A6, 04-Oct-00