CXA2534Q 4-Channel CD Motor Driver Description CXA2534Q is a 4-channel H-bridge motor driver IC designed for portable CD systems. It has a built-in DC to DC converter controller that allows voltage step-up to typically 3.2 V; this voltage can be used to power the system DSP, SSP and micro-controller. In addition, it also provides a PWM regulated power supply to the H-bridge output stage so as to ensure high efficiency. 48 pin QFP (Plastic) Features • 4 channels of H-bridge drivers • PWM regulated power supply for H-bridge output stages • Step-up DC to DC converter controller for system power supply • Start and off controls with soft start capability • Reset pulse • Short circuit protect • Over-voltage protect • Low battery voltage detection • Rechargeable battery charger • General purpose operational amplifier • Thermal shut-down for battery charger and Hbridge driver (170 °C/140 °C) • Direct interface with wired remote controller possible Applications Portable CD player Structure Bipolar silicon monolithic IC Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits. —1— E99145-TE CXA2534Q Absolute Maximum Ratings (Ta=25 °C) Item Supply voltage Spindle channel output current Sled channel output current Focus channel output current Track channel output current Allowable power dissipation operating temperature Storage temperature Symbol VCC1, VCC2, PVCC Io (spindle) Io (sled) Io (focus) Io (track) PD Topr Tstg Rating 13.5 400 300 200 200 660 –20 to +75 –65 to +150 Unit V mA mA mA mA mW °C °C Recommended Operating Conditions (Ta=25 °C) Item System 1 supply voltage System 2 supply voltage Power VCC Battery supply voltage Battery charger supply voltage Operating temperature Symbol VCC1 VCC2 PVCC Batt ChgVCC Ta Min 2.7 2.7 — Typ 3.2 3.2 PWM Max 5.5 5.5 Batt Unit V V V 1.5 3 –10 2.4 4.5 25 8 8 70 V V °C —2— CXA2534Q MUTE 12 13 SP IN 11 SP MUTE 14 PGND 10 PVCC 15 SL BRAKE 9 TRACK– 16 SLED IN 8 TRACK+ 17 FT MUTE 7 FOCUS– 18 FOCUS IN 6 FOCUS+ 19 TRACK IN 5 PVCC 20 VCC2 4 SLED– 21 VREF 3 SLED+ 22 VCC1 2 SP– 23 OP+ 1 SP+ 24 25 RESET EMP Block Diagram OP O 29 START 30 KEY IN 33 GND 34 ISET PEAK DETECT PWM DRIVER PREDRIVER PREDRIVER EMPTY DETECT WIRED REMOTE PRETRIANGLE DRIVER WAVE GEN POWER ON/OFF OVER VOLTAGE PROTECT RESET ERROR GND SW DRIVER SHORT PROTECT 37 38 39 40 41 42 43 44 45 46 47 48 SEL BSEN BATT SW DEAD EO EI SPRT TR TC CLK OP– 36 TSD CHGVCC BTL PREDRIVER CHARGER DC IN 35 REMO BATT BTL TSD BRAKE 28 PSW BTL MUTE 27 PGND BTL 32 PWMFIL 31 OFF 26 PGND —3— CXA2534Q Pin Description Pin No. Symbol Pin Voltage Equivalent circuit Description VCC1 VCC1 1 OP O — Output pin of built-in operational amplifier 1 VCC1 2 VCC1 Non-inverting input pin of operational amplifier OP+ 2 48 — 48 OP– 3 VCC1 Inverting input pin of operational amplifier Power supply input to DC-DC controller circuits 3.2 V VCC2 ×4 4 4 VREF 1.6 V Reference Voltage 30k 75k 5 VCC2 3.2 V Power supply input to pre-driver circuits —4— CXA2534Q Pin No. Symbol 6 TRACK IN 7 FOCUS IN Pin Voltage Equivalent circuit Description VCC2 1.6 V Tracking error signal input pin Focus error signal input pin 6 11k 7 9 9 SLED IN Sled error signal input pin VCC2 8 FT MUTE Focus and Tracking mute input pin 0V 8 75k 10 10 75k SL BRAKE Sled motor brake input pin 11 PGND 0V Power ground for H-bridge drivers 28 VCC2 12 SP IN 1.6 V Spindle error signal input pin 12 7.5k VCC2 75k 13 SP MUTE 0V 75k 13 75k 75k —5— Spindle mute input CXA2534Q Pin No. Symbol Pin Voltage PVCC — Equivalent circuit Description 14 Power supply input for H-bridge drivers 19 15 TRACK– 16 TRACK+ 17 FOCUS– 18 FOCUS+ Negative output pin to tracking motor 14 Negative output pin to focus motor — 20 SLED– 21 SLED+ 22 SP– 23 SP+ Positive output pin to tracking motor 19 16 15 18 17 20 19 22 21 Positive output pin to focus motor Negative output pin to sled motor Positive output pin to sled motor 11 Negative output pin to spindle motor 28 Positive output pin to spindle motor 24 24 EMP Battery empty detection output pin — VCC1 VCC1 90k 25 RESET VCC1 25 Reset output pin —6— CXA2534Q Pin No. Symbol Pin Voltage Equivalent circuit VCC1 Description VCC1 180k 26 OFF VCC1 30k Input pin to put IC into standby mode 26 VCC2 VCC2 2k 27 PWMFIL — 27 PWM filter pin 2k BATT BATT 29 29 PSW — PWM switching output pin 15 —7— CXA2534Q Pin No. Symbol Pin Voltage Equivalent circuit BATT Description BATT 390k 30 START Batt 200k 30 Input pin to start the IC 32 31 KEY IN Input pin from wired remote to start the IC — 200k 50k 31 32 REMO BATT Power supply to the built-in wired remote interface circuit — BATT 30k 33 33 DC IN 0V 34 GND 0V 100k Input pin to start the IC when AC adapter is inserted Ground CHGVCC 35 ISET 1.2 V 36 CHGVCC 4.5 V Set charging current of built-in battery charger 950 35 Power supply input to the battery charger —8— CXA2534Q Pin No. Symbol Pin Voltage Equivalent circuit Description BATT 220k 68k 37 SEL — 30k 37 Detection input pin for battery or AC adapter operation and Battery charging current output pin BATT 38 16.5k 71k 38 BSEN Batt Detection input pin for battery empty detection 19k 10k 11.5k 39 BATT 2.4 V Battery input pin BATT BATT 40 SW — BATT 250 40 9k —9— DC to DC controller output pulses CXA2534Q Pin No. Symbol Pin Voltage Equivalent circuit Description VCC1 18k 41 DEAD 0.88 V 41 Soft start pin 65k 50k VCC1 42 EO — VCC1 Output pin of error amplifier 42 VCC1 VCC1 35k 43 EI 1.2 V Input pin of error amplifier 43 21k VCC1 44 SPRT 0V VCC1 Short protection pin 44 220k —10— CXA2534Q Pin No. Symbol Pin Voltage Equivalent circuit Description VCC1 Together with the capacitor at TC, set the start-up and free running frequency of sawtooth 5k 45 TR 1.2 V 45 VCC1 BATT ×3 46 TC — 46 ×2 Together with the resistor at TR, set the start-up and free running frequency of sawtooth 420k VCC1 10k 47 CLK — 47 Synchronizing clock pulse input —11— CXA2534Q Electrical Specifications If not specified, Ta=25 °C, Batt=2.4 V, VCC1=VCC2=3.2 V, Vref=1.6 V, ChgVCC=0 V, fCLK=88.2 kHz Item Symbol Min. Typ. Max. Unit 0 2 µA 3.2 mA PVCC=PWM, FT Mute=3.2 V Condition 1. Overall Batt standby current IST — Batt quiescent current IBAT — 2 VCC1 quiescent current IVCC1 — 4.9 6.7 mA PVCC=0.45 V, FT Mute=3.2 V, EI=0 V VCC2 quiescent current IVCC2 4.2 6.4 mA PVCC=0.45 V, FT Mute=3.2 V ChgVCC quiescent current IChgVCC 0.79 1.2 mA ChgVCC=4.5 V, Rch=open 21.9 23.9 Batt=9 V, VCC1=VCC2=0 V 2. H-Bridge driver Spindle Gv (sp) 25.9 dB Sled Gv (sled) 14 15.5 17 dB Focus Gv (focus) 14 15.5 17 dB Track Gv (track) 14 15.5 17 dB ∆Gv –2 0 2 dB Spindle Rin (sp) 5.7 7.5 11 kΩ Sled Rin (sled) 8.8 11 15 kΩ Focus Rin (focus) 8.8 11 15 kΩ Track Rin (track) 8.8 11 15 kΩ Spindle Vom (sp) 1.9 2.1 — V Maximum Sled Vom (sl) 1.9 2.05 — V output voltage Focus Vom (foc) 1.9 2.05 — V Track Vom (tra) 1.9 2.05 — V Spindle VSAT (sp) — 280 400 mV Io=400 mA, SP IN=0 and 3.2 V Sled VSAT (sl) — 280 400 mV Io=300 mA, SLED IN=0 and 3.2 V Focus VSAT (foc) — 230 400 mV Io=200 mA, FOCUS IN=0 and 3.2 V Track VSAT (tra) — 230 400 mV Io=200 mA, TRACK IN=0 and 3.2 V Spindle VSATL (sp) — 230 400 mV Io=400 mA, SP IN=0 and 3.2 V Sled VSATL (sl) — 250 400 mV Io=300 mA, SLED IN=0 and 3.2 V Focus VSATL (foc) — 200 400 mV Io=200 mA, FOCUS IN=0 and 3.2 V Track VSATL (tra) — 200 400 mV Io=200 mA, TRACK IN=0 and 3.2 V VOI –5 0 5 mV –50 0 50 mV Voltage gain Gain difference Input impedance Upper Tr saturation voltage Lower Tr saturation voltage Input offset voltage IN∗=1.7 and 1.8 V IN=0 and 3.2 V, PVCC=4 V Spindle VOO (sp) Output offset Sled VOO (sled) voltage Focus VOO (focus) Track VOO (track) Spindle VDB (sp) –5 20 45 mV Sled VDB (sled) –10 15 40 mV Focus VDB (focus) –10 15 40 mV Track VDB (track) –10 15 40 mV SP IN=1.8V Dead band Vref=IN=1.6 V Spindle mute on VMSP(on) 2 — — V SP IN=1.8V Spindle mute off VMSP(off) — — 0.8 V SLED IN=1.8V Sled brake on VBSL(on) 2 — — V SLED IN=1.8V Sled brake off VBSL(off) — — 0.8 V ∗ IN means SP IN, SLED IN, FOCUS IN or TRACK IN. —12— CXA2534Q Min. Typ. Max. Unit Focus/Track mute on Item VMFT (on) — — 0.8 V FOCUS IN=1.8 V Focus/Track mute off VMFT (off) 2 — — V FOCUS IN=1.8 V Vref on voltage Vref (on) 1.2 — — V SP IN=1.8 V Vref off voltage Vref (off) — — 0.8 V SP IN=1.8 V PSW output current IPSW 10 13 17 mA PVCC shift voltage VSHIF 0.2 0.3 0.4 V PVCC leakage current IPVCC (leakage) PWM transconductance GPWM Symbol Condition 3. PWM driver for PVCC — 0 3 µA 1/67.5 1/50 1/32.5 1/kΩ SLED IN=2.1 V SLED IN=1.8 V, PVCC–SLED+ PVCC=9 V, VCC1=VCC2=Batt=0 V SL IN=1.8 V, PVCC=1.2 to 1.4 V 4. DC to DC converter 4.1 Error amplifier VCC1 threshold voltage VCC1TH 3.05 3.2 3.37 V Hi error output voltage VEOH 1.5 1.65 — V EI=0.7 V, Io=–100 µA Lo error output voltage VEOL — — 0.2 V EI=1.36 V, Io=100 µA 4.2 Short circuit and Over voltage protection SPRT voltage (normal) VSPR — 0.05 0.1 V EI=1.36 V SPRT output current (EO=H) ISPR1 6 10 16 µA EI=0.7 V, VSPR=0 V SPRT output current (OFF=L) ISPR2 12 20 32 µA EI=1.36 V, OFF=0 V, VSPR=0 V ISPR3 12 20 32 µA EI=1.36 V, Batt=9.5 V, VSPR=0 V SPRT impedance RSPR 154 220 297 kΩ SPRT threshold voltage VSPR (Th) 1.1 1.23 1.36 V EI=0.7 V, TC=0 V Over voltage protect threshold VBSEN (Th) 8 8.4 9 V BSEN Voltage VSWH (start) 0.78 0.98 1.13 V VSWH (nor) 1 1.5 — V SW low output voltage VSWL (nor) — 0.1 0.4 V SW start freq fSW1 55 85 115 kHz SW free running freq fSW2 60 70 82 kHz TC=420 pF, CLK=0 V SW synchronized freq fSW3 — 88.2 — kHz TC=420 pF, CLK=88.2 kHz Start freq duty cycle DSW1 45 55 65 % TC=420 pF, VCC1=VCC2=0 V Free freq duty cycle DSW2 70 80 90 % TC=420 pF, EI=0.7 V, CLK=0 V Synchronized freq duty cycle DSW3 65 75 85 % TC=420 pF, EI=0.7 V DEAD pin impedance RDEAD 55 80 105 kΩ DEAD pin voltage VDEAD 0.72 0.82 0.92 V SPRT output current (Over-voltage) 4.3 Sawtooth waveform SW high output voltage (Starting) SW high output voltage (Normal) 4.4 Soft start —13— Batt=TC=1.5 V, VCC1=VCC2=0 V, Io=–2 mA, START=LO TC=0 V, Io=–10 mA, EI=0.7 V SPRT=0 V TC=2 V, Io=10 mA TC=420 pF, VCC1=VCC2=0 V, START=LO CXA2534Q Item Symbol Min. Typ. Max. Unit Condition 4.5 Input OFF threshold voltage VOFF (th) — — VCC–2 V EI=1.36 V OFF current IOFF 55 80 105 µA OFF=0 V START on threshold voltage VSTART1 — — Batt–1 V VCC1=VCC2=0 V, TC=2 V — — V VCC1=VCC2=0 V, TC=2 V 9 14 19 µA START=0 V START off threshold voltage VSTART2 START pin current ISTART Batt– 0.3 High VCLKH 2 — — V Low VCLKL — — 0.8 V ICLK — 5 10 µA Start cut threshold voltage VST (th) 2.3 2.5 2.7 V Start cut hysteresis VST (hs) — 200 — mV Discharge threshold voltage VDIS 1.25 1.45 1.65 V Empty detect threshold 1 VEMPT1 1.9 2.0 2.1 V VSEL=0 V (SEL=LOW) Empty detect threshold 2 VEMPT2 1.5 1.6 1.7 V ISEL=–2 µA (SEL=HI Z) Empty detect hysteresis VEMPH1 — 50 — mV VSEL=0 V (SEL=LOW) Empty detect hysteresis VEMPH2 — 50 — mV ISEL=–2 µA (SEL=HI Z) EMPTY pin voltage VEMP — — 0.5 V Io=1 mA, BSEN=1 V EMPTY pin leakage current IEMPL — — 1 µA BSEN=2.4 V BSEN pin impedance RBSEN 16.5 22.8 29 kΩ VSEL=0 V BSEN pin leakage current IBSENL — — 1 µA VCC1=VCC2=0 V, BSEN=4.5 V SEL pin threshold voltage VSEL (th) 1.3 — — V VSEL (th)=Batt–SEL, BSEN=2 V SEL pin threshold current ISEL (th) –2 — — µA Reset threshold voltage VRST (th) 85 90 95 % Reset hysteresis VRST (hy) — 50 — mV RESET pin VRST — — 0.4 V RESET pin impedance RRST 66 88 118 kΩ Input bias current IBIAS — — 250 nA Input offset voltage VIO –5 0 5 mV High output voltage VOH 2.9 — — V RL=open Low output voltage VOL — — 0.2 V RL=open Output current (Source) ISOU — –8.5 –3 mA RL=50 Ω to GND Output current (Sink) ISIN 0.4 0.8 — mA RL=50 Ω to VCC1 Open loop gain GVO — 70 — dB Vin=–75 dB, f=1 kHz Slew rate SR 0.5 1 1.5 V/µS Clock input voltage Clock current CLK=3.2 V 4.6 Start VCC1=VCC2=0 V→3.2 V, START=0 V START=0 V 5. EMPTY 6. RESET Io=1 mA, VCC1=VCC2=2.8 V 7. OP AMP —14— OP+=1.6 V CXA2534Q Item Symbol Min. Typ. Max. Unit Condition 8. BATTERY CHARGER ChgVCC=4.5 V, ISET=1.8 kΩ RCHG pin voltage VRCHG 0.7 0.8 0.9 V RCHG pin impedance RRCHG 0.68 0.96 1.16 kΩ ChgVCC=4.5 V, ISET=0.5 and 0.6 V ISEL1 — — 1 µA ChgVCC=4.5 V, ISET=open ISEL2 — — 1 µA ChgVCC=0.6 V, ISET=1.8 kΩ VSEL — 0.45 1 V ChgVCC=4.5 V, Io=300 mA, ISET=0 Ω SEL pin leakage current (RCHG=open) SEL pin leakage current (ChgVCC=0.6 V) SEL pin voltage 9. WIRED REMOTE INTERFACE DC IN pin threshold voltage VDCIN (th) 1 — — V KEY IN pin threshold current IKEYIN (th) — — 5 µA —15— Batt=4 V, VCC1=VCC2=0 V, TC=2 V, DC=IN=from 0 to 3 V Batt=4 V, VCC1=VCC2=0 V, TC=2 V, IKEYIN=from 0 to 10 µA 0.1µ C10 2SA1585S RB400D D1 47µ C1 P1 L1 33µH C2 C3 R1 R100 10p 2200p I6 B A A B B V20 1.8k V19 B A B A R2 100k A V100 V17 B A 47 B V18 A B A I7 V16 V15 S27 S26 S24 S23 S22 S20 S19 S18 V13 V21 S17_2 R6 R4 I3 8,1.5W R9 8,1.5W R7 I2 I1 36 CHGVCC 35 ISET 34 GND 33 DC IN 32 REMO BATT 31 KEY IN 30 START 29 PSW 28 PGND 27 PWMFIL 26 OFF 25 RESET V22 A I8 BA B S28 S29 R5 10k I9 I12 I13 B V24 V25 V26 I10 I11 B A A BA B A B A S30 S31 S32 S33 S34 V23 CXA2534 IC01 C4 470p A PGND 11 SP IN 12 OP O 1 OP+ 2 Vcc1 3 VREF 4 Vcc2 5 TRACK IN 6 FOCUS IN 7 FT MUTE 8 SLED IN 9 A V28 B V29 C S36_1 S36_2 V27 S35 R8 39k S8 B A V11 SL BRAKE 10 B A B C B AA BB AA B B AA B B AA B S17_1 S16 S15 S14 S13 S12 S11 S10 S9 8,1.5W 8,1.5W SP– 22 39 BATT I5 R3 51k SLED+ 21 40 SW V12 I4 SLED– 20 41 DEAD S21 FOCUS– 17 44 SPRT A TRACK+ 16 45 TR 13 SP MUTE V14 TRACK– 15 46 TC EMP 24 37 SEL PVcc 19 42 EO SP+ 23 38 BSEN FOCUS+ 18 43 EI PVcc 14 47 CLK —16— 48 OP– B C3 R10 10k S38_2 S38_1 D C B A 1M V7 470µ R12 100k R13 20k R14 A S25 B R15 S37 S2 A B 50 S1 A B S4 B A S3 B A S6 B A S5 B A A S7 B A B 1k V1 SIG R11 V3 V4 V2 V200 V5 V6 V8 V9 V10 CXA2534Q Electrical Characteristics Test Circuit CXA2534Q Application Circuit Spindle Motor SLED Motor Focus Coil Tracking Coil 40 SP MUTE 12 11 10 9 8 7 FOCUS IN 6 TRACK IN 5 VCC2 4 BRAKE MUTE FT MUTE VREF 3 PVCC TRACK– TRACK+ FOCUS– FOCUS+ PVCC 41 42 43 EI 39 0.1µ 8.2k 44 45 0.022µ 46 47 0.1µ 39k 470p GND GND GND PGND SLED IN VCC1 OP+ OP O SHORT PROTECT EO 38 SL BRAKE GND SW DRIVER DEAD SEL 37 PGND 2 CHARGER TSD ERROR SW WIRED REMOTE BOARD 35 ISET 1.4k CHGVCC OVER VOLTAGE PROTECT RESET SP IN 1 WIRED REMOTE PRETRIANGLE DRIVER WAVE GEN POWER ON/OFF TC 32 EMPTY DETECT GND GND SLED– SP– SP+ PREDRIVER BSEN GND F. R. PREDRIVER 36 F. F. 13 BTL TR 30 KEY IN DC IN 0.1µ BTL TSD PEAK DETECT PWM DRIVER 33 STOP BTL SPRT 29 START REMO BATT 14 PREDRIVER 34 GND 15 25 PSW 1µ PLAY/PAUSE 16 PGND PLAY GND 17 26 BTL 47 PGND 18 48 OP– GND 31 GND 19 CLK 10p 100k PGND 2200p 20 MUTE BATT 33µH 21 DC-DC CONVERTOR AC Adapter Input 47µ 100µ GND GND GND Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same. —17— Servo Processor PWMFIL 22 27 OFF 23 28 0.1µ PGND PGND 47µ 24 RESET SLED+ To System Micro Controller EMP To System Micro Controller CXA2534Q Description of Operation 1. H-Bridge Driver a) Gain Setting The input resistances of the Sled, Focus and Track channels are 11 kΩ (typical); the input resistance of the Spindle channel is 7.5 kΩ (typical). The gain can be adjusted by connecting a external resistor, R at the input pin of the channel. Channel Sled channel Focus channel Track channel Spindle channel Unit GV = 20 log 55 kΩ 11 kΩ + R dB GV = 20 log 110 kΩ 7.5 kΩ + R dB R - External Resistor b) Mute The Spindle channel operates normally when the SP MUTE (pin 13) is open or at LOW (below 0.8 V). The output will be muted when the SP MUTE pin is at HIGH (above 2 V). This is a high impedance mute as the spindle output voltage will be not pulled to LOW. The Focus and Track channels share the same mute pin (pin 8). The channels are muted when the FT MUTE pin (pin 8) is open or at LOW level (below 0.8 V). When the Focus and Track channels are muted, the quiescent current at the VCC2 pin is also reduced by almost half. This is because the bias are removed when the mute is on. c) Thermal Shutdown The H-bridge Driver has an internal thermal shutdown circuit. All the channels outputs will be muted when the chip temperature exceeds 170 °C (typical) and restored when the chip temperature falls to 140 °C (typical). d) VREF pin When the VREF pin (pin 4) is below 1 V (typical), the H-bridge driver will be at standby mode and the quiescent current is zero (typical). e) Dead Band Dead band = 2 × input Resistance (attached external resistor + internal resistor) × 0.5 µA The dead band is depended on input resistance. Thus, the dead band varies with the gain settings. The dead band is 7.5 mV for Spindle channel and 11 mV for Sled, Focus and Track channels. —18— CXA2534Q f) PWM Driver For PVCC To ensure the good power efficiency of the H-bridge driver, a Buck DC-to-DC converter may be used to regulate the PVCC. The controller selects the peak voltage among the channels and used it to control the duty cycle of the PWM. External components necessary are: PNP transistor, inductor coil, diode and capacitors. The configuration of a Buck DC-to-DC converter is shown as follow: BATT 33µ 10pF 47µF 2200pF 0.1µF 100k 47 PWMFIL 27 PSW PVCC 29 14 PVCC 19 CXA2534Q g) Bypass Capacitor To have prevent noise, a bypass capacitor (roughly 0.1 µF) is connected from PVCC pin to the GND pin as close as possible. —19— CXA2534Q 2. DC-to-DC Converter a) VCC1 Voltage Setting The VCC1 voltage can be adjusted by varying the two external resistors, R1 and R2. The formula for VCC1 Voltage setting is: R1R3 VCC1 = 1.23 R2R4 + R1+R3 R2+R4 R2R4 R2+R4 (V) where R1 - External Resistor R2 - External Resistor R3 - 35 kΩ R4 - 21 kΩ CXA2534Q VCC1 3 R1 R3 EI 43 R2 R4 1.23V b) Short Circuit Protection If the VCC1 falls below the designed voltage for a long time, it will be considered as a short circuit at the VCC1. In this case, the IC will detect this prolong drop in VCC1 and turn off the IC. When the VCC1 is below the designed voltage, the error amplifier will output an HIGH at its EO pin (pin 42). The High level at EO pin will cause the SPRT pin’s capacitor (pin 44) to charge up by a constant current of 10 µA. Once the voltage is above 1.23 V (typical), the IC will turn off. The duration of the short circuit can be varied by the SPRT pin’s capacitor. t= 1.23V × CSPRT 10µA (sec) —20— CXA2534Q c) Soft Start During start-up of the IC, the duty cycle of the DC-to-DC converter is increased slowly to a maximum of 80 %. The VCC1 voltage will also increase slowly. This is known as soft start. During the soft start, the duty cycle of the SW pin (pin 40) is dependent on the voltage at the DEAD pin (pin 41). The DEAD pin is connected to a capacitor which is being charged up by an internal resistance of 65 kΩ. Therefore, the time taken for the duty cycle to reach the maximum is t = CSPRT × R (sec) where R = 65 kΩ d) Power Off To turn off the DC-to-DC Converter, a LOW level is applied to the OFF pin (pin 26). When the OFF pin is low, the IC will not turn off the DC-to-DC converter immediately but will charge up the SPRT pin’s capacitor with a constant current of 20 µA. Once the SPRT pin’s voltage is above 1.23 V, the IC will then shut down. Therefore, the delay is given by the formula below: t= 1.23 V × CSPRT 20 µA (sec) e) Over-Voltage Protection The IC will detect a over-voltage if the voltage at the BSEN pin is above 8.4 V (typical). When overvoltage occurred, the IC will shut down after a time delay. The time delay is determined by the time taken for the SPRT pin’s capacitor to charge above 1.23 V. The charging current for the SPRT pin capacitor is constant and is 20 µA. t= 1.23 V × CSPRT 20 µA (sec) f) Reset Pulse When the VCC1 voltage rises above 90 % of the designed value, the RESET pin (pin 25) will change from LOW level to HIGH level. A hysteresis of 50 mV (typical) is implemented to prevent the ‘chattering’ of the output at RESET pin. g) Empty Detection The EMP pin (pin 24) is used to indicate low battery voltage. When the BSEN pin falls below a certain threshold voltage, the EMP pin will change from HIGH to LOW level. There are two threshold voltages, depending on the SEL pin (pin 37). In order to prevent ‘chattering’ of the output at the EMP pin, a hysteresis of 50 mV (typical) is implemented. SEL pin LOW High - Z Threshold Voltage (typical) 2.0 V 1.6 V —21— Recovery Voltage (typical) 2.05 V 1.65 V CXA2534Q 3. Battery Charger The Battery Charger is separated from the rest of the circuit. The ChgVCC pin (pin 36) is the power supply pin to the charger circuit. The charging current is drawn in from the SEL pin (pin 37) and can be set by an external resistor at ISET pin (pin 35). The charger has a built-in thermal shut down circuit. The shut down temperature is set to 170 °C and 140 °C is the recovery temperature. 4. Wired Remote Interface When the IC is at standby, it can be activated by pulling the START pin (pin 30) or the KEY IN pin (pin 31) LOW. The START pin is controlled by the PLAY button on the main set and the KEY IN pin is controlled by the PLAY button on the wired remote control panel. The wired remote interface circuit is powered at REMO BATT pin (pin 32) which is connected to the BATT. To ensure that the voltage at REMO BATT pin is not greater than VCC1, a resistor and zener diode (Vz=3.1 V) may be necessary. The DC IN pin (pin 33) will detect a pulse through a series capacitor when a AC adapter is power on. This pulse will activate the IC also. —22— CXA2534Q Package Outline Unit : mm 48PIN QFP (PLASTIC) 15.3 ± 0.4 + 0.1 0.15 – 0.05 + 0.4 12.0 – 0.1 0.15 36 25 24 13.5 37 48 + 0.2 0.1 – 0.1 13 12 0.8 + 0.15 0.3 – 0.1 0.24 M 0.9 ± 0.2 1 + 0.35 2.2 – 0.15 PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN SONY CODE QFP-48P-L04 LEAD TREATMENT SOLDER / PALLADIUM PLATING EIAJ CODE QFP048-P-1212 LEAD MATERIAL 42/COPPER ALLOY PACKAGE MASS 0.7g JEDEC CODE NOTE : PALLADIUM PLATING This product uses S-Pd PPF (Sony Spec.-Palladium Pre-Plated Lead Frame). —23—