Order this document by TL594/D The TL594 is a fixed frequency, pulse width modulation control circuit designed primarily for Switchmode power supply control. • • • • • • • • PRECISION SWITCHMODE PULSE WIDTH MODULATION CONTROL CIRCUIT SEMICONDUCTOR TECHNICAL DATA Complete Pulse Width Modulation Control Circuitry On–Chip Oscillator with Master or Slave Operation On–Chip Error Amplifiers On–Chip 5.0 V Reference, 1.5% Accuracy Adjustable Deadtime Control D SUFFIX PLASTIC PACKAGE CASE 751B (SO–16) Uncommitted Output Transistors Rated to 500 mA Source or Sink Output Control for Push–Pull or Single–Ended Operation Undervoltage Lockout N SUFFIX PLASTIC PACKAGE CASE 648 PIN CONNECTIONS Noninv Input 1 Inv Input 2 MAXIMUM RATINGS (Full operating ambient temperature range applies, unless otherwise noted.) Rating Symbol Value Unit Power Supply Voltage VCC 42 V Collector Output Voltage VC1, VC2 42 V Collector Output Current (each transistor) (Note 1) IC1, IC2 500 mA Amplifier Input Voltage Range VIR –0.3 to +42 V Power Dissipation @ TA ≤ 45°C PD 1000 mW RθJA 80 °C/W TJ 125 °C Tstg –55 to +125 °C Thermal Resistance, Junction–to–Ambient Operating Junction Temperature Storage Temperature Range Operating Ambient Temperature Range TL594ID, CN TL594CD, IN TA Derating Ambient Temperature TA 5.0 V REF ≈ 0.1 V °C 45 Inv 15 Input 14 Vref 12 VCC Oscillator 11 C2 Q2 Ground 7 C1 8 10 E2 Q1 9 E1 (Top View) ORDERING INFORMATION Device TL594CD °C Noninv 16 Input Output 13 Control CT 5 TL594CN TL594IN Operating Temperature Range TA = 0° to +70°C TA = – 25° to +85°C Motorola, Inc. 1996 MOTOROLA ANALOG IC DEVICE DATA + 2 Error Amp – VCC RT 6 0 to +70 –25 to +85 NOTES: 1. Maximum thermal limits must be observed. Compen/PWN Comp Input 3 Deadtime Control 4 + Error 1 Amp – Package SO–16 Plastic Plastic Rev 0 1 TL594 RECOMMENDED OPERATING CONDITIONS Characteristics Power Supply Voltage Collector Output Voltage Collector Output Current (Each transistor) Amplified Input Voltage Current Into Feedback Terminal Symbol Min Typ Max Unit VCC VC1, VC2 7.0 15 40 V – 30 40 V IC1, IC2 Vin – – 200 mA 0.3 – V – – VCC – 2.0 0.3 mA – – 10 mA kΩ Timing Resistor lfb lref RT 1.8 30 500 Timing Capacitor CT 0.0047 0.001 10 µF Oscillator Frequency fosc – 1.0 40 200 kHz 0.3 – 5.3 V Reference Output Current PWM Input Voltage (Pins 3, 4, 13) ELECTRICAL CHARACTERISTICS (VCC = 15 V, CT = 0.01 µF, RT = 12 kΩ, unless otherwise noted.) For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies, unless otherwise noted. Characteristics Symbol Min Typ Max Unit 4.925 4.9 5.0 – 5.075 5.1 – 2.0 25 mV Load Regulation (IO = 1.0 mA to 10 mA) Regline Regload – 2.0 15 mV Short Circuit Output Current (Vref = 0 V) ISC 15 40 75 mA IC(off) IE(off) – 2.0 100 µA – – –100 µA VSAT(C) VSAT(E) – – 1.1 1.5 1.3 2.5 IOCL IOCH tr – – 0.1 2.0 – 20 – – 100 100 200 200 – – 40 40 100 100 VIO IIO – 2.0 10 – 5.0 250 nA IIB VICR – –0.1 –1.0 µA REFERENCE SECTION Reference Voltage (IO = 1.0 mA, TA = 25°C) (IO = 1.0 mA) Line Regulation (VCC = 7.0 V to 40 V) Vref V OUTPUT SECTION Collector Off–State Current (VCC = 40 V, VCE = 40 V) Emitter Off–State Current (VCC = 40 V, VC = 40 V, VE = 0 V) Collector–Emitter Saturation Voltage (Note 2) Common–Emitter (VE = 0 V, IC = 200 mA) Emitter–Follower (VC = 15 V, IE = –200 mA) Output Control Pin Current Low State (VOC ≤ 0.4 V) High State (VOC = Vref) Output Voltage Rise Time Common–Emitter (See Figure 13) Emitter–Follower (See Figure 14) Output Voltage Fall Time Common–Emitter (See Figure 13) Emitter–Follower (See Figure 14) V µA ns tf ns ERROR AMPLIFIER SECTION Input Offset Voltage (VO (Pin 3) = 2.5 V) Input Offset Current (VO (Pin 3) = 2.5 V) Input Bias Current (VO (Pin 3) = 2.5 V) Input Common Mode Voltage Range (VCC = 40 V, TA = 25°C) Inverting Input Voltage Range Open Loop Voltage Gain (∆VO = 3.0 V, VO = 0.5 V to 3.5 V, RL = 2.0 kΩ) VIR(INV) AVOL 0 to VCC–2.0 mV V –0.3 to VCC–2.0 V 70 95 – fC φm – 700 – kHz – 65 – deg. Common Mode Rejection Ratio (VCC = 40 V) CMRR 65 90 – dB Power Supply Rejection Ratio (∆VCC = 33 V, VO = 2.5 V, RL = 2.0 kΩ) PSRR – 100 – dB IO– IO+ 0.3 0.7 – mA –2.0 –4.0 – mA Unity–Gain Crossover Frequency (VO = 0.5 V to 3.5 V, RL = 2.0 kΩ) Phase Margin at Unity–Gain (VO = 0.5 V to 3.5 V, RL = 2.0 kΩ) Output Sink Current (VO (Pin 3) = 0.7 V) Output Source Current (VO (Pin 3) = 3.5 V) dB NOTE: 2. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient temperature as possible. 2 MOTOROLA ANALOG IC DEVICE DATA TL594 ELECTRICAL CHARACTERISTICS (VCC = 15 V, CT = 0.01 µF, RT = 12 kΩ, unless otherwise noted.) For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies, unless otherwise noted. Characteristics Symbol Min Typ Max Unit VTH – 3.6 4.5 V II– 0.3 0.7 – mA Input Bias Current (Pin 4) (VPin 4 = 0 V to 5.25 V) IIB (DT) – –2.0 –10 µA Maximum Duty Cycle, Each Output, Push–Pull Mode (VPin 4 = 0 V, CT = 0.01 µF, RT = 12 kΩ) (VPin 4 = 0 V, CT = 0.001 µF, RT = 30 kΩ) DCmax 45 – 48 45 50 – – 0 2.8 – 3.3 – – 9.2 9.0 40 10 – – 10.8 12 σfosc – 1.5 – % Frequency Change with Voltage (VCC = 7.0 V to 40 V, TA = 25°C) ∆fosc (∆V) – 0.2 1.0 % Frequency Change with Temperature (∆TA = Tlow to Thigh, CT = 0.01 µF, RT = 12 kΩ) ∆fosc (∆T) – 4.0 – % 4.0 3.5 5.2 – 6.0 6.5 100 50 150 150 300 300 – – 8.0 8.0 15 18 – 11 – PWM COMPARATOR SECTION (Test Circuit Figure 11) Input Threshold Voltage (Zero Duty Cycle) Input Sink Current (VPin 3 = 0.7 V) DEADTIME CONTROL SECTION (Test Circuit Figure 11) Input Threshold Voltage (Pin 4) (Zero Duty Cycle) (Maximum Duty Cycle) VTH % V OSCILLATOR SECTION Frequency (CT = 0.001 µF, RT = 30 kΩ) (CT = 0.01 µF, RT = 12 kΩ, TA = 25°C) (CT = 0.01 µF, RT = 12 kΩ, TA = Tlow to Thigh) Standard Deviation of Frequency* (CT = 0.001 µF, RT = 30 kΩ) fosc kHz UNDERVOLTAGE LOCKOUT SECTION Turn–On Threshold (VCC Increasing, Iref = 1.0 mA) TA = 25°C TA = Tlow to Thigh Vth Hysteresis TL594C,I TL594M VH V mV TOTAL DEVICE Standby Supply Current (Pin 6 at Vref, All other inputs and outputs open) (VCC = 15 V) (VCC = 40 V) ICC Average Supply Current (VPin 4 = 2.0 V, CT = 0.01 µF, RT = 12 kΩ, VCC = 15 V, See Figure 11) * Standard deviation is a measure of the statistical distribution about the mean as derived from the formula, σ MOTOROLA ANALOG IC DEVICE DATA mA mA N Σ (Xn – X)2 n=1 N–1 3 TL594 Figure 1. Representative Block Diagram VCC Output Control 13 8 6 D Oscillator RT CT 5 – ≈ 0.12V Q Q1 Q Q2 11 Deadtime Comparator Ck + 4 Deadtime Control 9 Flip– Flop 10 ≈ 0.7V – + 1 2 – 1 2 Error Amp 1 + PWM Comparator 0.7mA 12 – + 3 UV Lockout + – 3.5V 15 Feedback PWM Comparator Input Reference Regulator – + VCC 4.9V 16 14 Error Amp 2 Ref. Output 7 Gnd This device contains 46 active transistors. Figure 2. Timing Diagram Capacitor CT Feedback/PWM Comp. Deadtime Control Flip–Flop Clock Input Flip–Flop Q Flip–Flop Q Output Q1 Emitter Output Q2 Emitter Output Control 4 MOTOROLA ANALOG IC DEVICE DATA TL594 APPLICATIONS INFORMATION Description The TL594 is a fixed–frequency pulse width modulation control circuit, incorporating the primary building blocks required for the control of a switching power supply. (See Figure 1.) An internal–linear sawtooth oscillator is frequency– programmable by two external components, RT and CT. The approximate oscillator frequency is determined by: 1.1 RT • CT For more information refer to Figure 3. Output pulse width modulation is accomplished by comparison of the positive sawtooth waveform across capacitor CT to either of two control signals. The NOR gates, which drive output transistors Q1 and Q2, are enabled only when the flip–flop clock–input line is in its low state. This happens only during that portion of time when the sawtooth voltage is greater than the control signals. Therefore, an increase in control–signal amplitude causes a corresponding linear decrease of output pulse width. (Refer to the Timing Diagram shown in Figure 2.) The control signals are external inputs that can be fed into the deadtime control, the error amplifier inputs, or the feedback input. The deadtime control comparator has an effective 120 mV input offset which limits the minimum output deadtime to approximately the first 4% of the sawtooth–cycle time. This would result in a maximum duty cycle on a given output of 96% with the output control grounded, and 48% with it connected to the reference line. Additional deadtime may be imposed on the output by setting the deadtime–control input to a fixed voltage, ranging between 0 V to 3.3 V. The pulse width modulator comparator provides a means for the error amplifiers to adjust the output pulse width from the maximum percent on–time, established by the deadtime control input, down to zero, as the voltage at the feedback pin varies from 0.5 V to 3.5 V. Both error amplifiers have a Output Function Grounded Single–ended PWM @ Q1 and Q2 1.0 Push–pull Operation 0.5 @ Vref common–mode input range from –0.3 V to (VCC – 2 V), and may be used to sense power–supply output voltage and current. The error–amplifier outputs are active high and are ORed together at the noninverting input of the pulse–width modulator comparator. With this configuration, the amplifier that demands minimum output on time, dominates control of the loop. When capacitor CT is discharged, a positive pulse is generated on the output of the deadtime comparator, which clocks the pulse–steering flip–flop and inhibits the output transistors, Q1 and Q2. With the output–control connected to the reference line, the pulse–steering flip–flop directs the modulated pulses to each of the two output transistors alternately for push–pull operation. The output frequency is equal to half that of the oscillator. Output drive can also be taken from Q1 or Q2, when single–ended operation with a maximum on–time of less than 50% is required. This is desirable when the output transformer has a ringback winding with a catch diode used for snubbing. When higher output–drive currents are required for single–ended operation, Q1 and Q2 may be connected in parallel, and the output–mode pin must be tied to ground to disable the flip–flop. The output frequency will now be equal to that of the oscillator. The TL594 has an internal 5.0 V reference capable of sourcing up to 10 mA of load current for external bias circuits. The reference has an internal accuracy of ±1.5% with a typical thermal drift of less than 50 mV over an operating temperature range of 0° to 70°C. f OSC, OSCILLATOR FREQUENCY (Hz) 100 k 10 k 1.0 k 500 1.0 k 2.0 k 5.0 k CT = 0.001 µF VCC = 15 V 0.01 µF 0.1 µF 10 k 20 k 50 k 100 k 200 k RT, TIMING RESISTANCE (Ω) MOTOROLA ANALOG IC DEVICE DATA 500 k 1.0 M Figure 4. Open Loop Voltage Gain and Phase versus Frequency A VOL, OPEN LOOP VOLTAGE GAIN (dB) Figure 3. Oscillator Frequency versus Timing Resistance 500 k fout fosc = Input/Output Controls 120 110 100 90 80 70 60 50 40 30 20 10 0 1.0 VCC = 15 V ∆VO = 3.0 V RL = 2.0 kΩ AVOL 10 100 1.0 k 10 k f, FREQUENCY (Hz) 100 k 0 20 40 60 80 φ 100 120 140 160 180 1.0 M φ , EXCESS PHASE (DEGREES) fosc ≈ Functional Table 5 % DT, PERCENT DEADTIME (EACH OUTPUT) Figure 5. Percent Deadtime versus Oscillator Frequency 20 18 16 CT = 0.001 µF 14 12 10 8.0 6.0 0.01 µF 4.0 2.0 0 500 k 1.0 k 10 k 100 k 500 k % DC, PERCENT DUTY CYCLE (EACH OUTPUT) TL594 VCC = 15 V VOC = Vref 1. CT = 0.01 µF 1. RT = 10 kΩ 2. CT = 0.001 µF 1. RT = 30 kΩ 2 30 20 10 0 0 1.0 2.0 3.0 Figure 7. Emitter–Follower Configuration Output Saturation Voltage versus Emitter Current Figure 8. Common–Emitter Configuration Output Saturation Voltage versus Collector Current 3.5 2.0 V CE(sat) , SATURATION VOLTAGE (V) V CE(sat) , SATURATION VOLTAGE (V) 1 40 VDT, DEADTIME CONTROL VOLTAGE (IV) 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 1.1 0 100 200 300 100 200 300 400 IC, COLLECTOR CURRENT (mA) Figure 9. Standby Supply Current versus Supply Voltage Figure 10. Undervoltage Lockout Thresholds versus Reference Load Current 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0 5.0 10 15 20 25 30 VCC, SUPPLY VOLTAGE (V) 35 40 V TH , UNDERVOLTAGE LOCKOUT THRESHOLD (V) IE, EMITTER CURRENT (mA) 9.8 0 0 400 10 I CC , SUPPLY CURRENT (mA) 50 fosc, OSCILLATOR FREQUENCY (Hz) 1.9 6 Figure 6. Percent Duty Cycle versus Deadtime Control Voltage 6.0 Turn On 5.5 Turn Off 5.0 4.5 4.0 0 5.0 10 15 20 25 30 35 40 IL, REFERENCE LOAD CURERNT (mA) MOTOROLA ANALOG IC DEVICE DATA TL594 Figure 11. Error–Amplifier Characteristics Figure 12. Deadtime and Feedback Control Circuit VCC = 15V Error Amplifier Under Test + Vin – Feedback Terminal (Pin 3) VCC Deadtime Test Inputs Feedback RT CT (+) (–) Error (+) (–) Output Control Gnd + – Vref Other Error Amplifier 50k Figure 13. Common–Emitter Configuration Test Circuit and Waveform 150 2W 150 2W C1 E1 Output 1 C2 E2 Output 2 Ref Out Figure 14. Emitter–Follower Configuration Test Circuit and Waveform 15V 15V RL 68 VC C Each Output Transistor C Each Output Transistor CL 15pF Q Q VEE E RL 68 E 90% VEE 90% 90% 90% CL 15pF VCC 10% 10% tr tf MOTOROLA ANALOG IC DEVICE DATA Gnd 10% 10% tr tf 7 TL594 Figure 15. Error–Amplifier Sensing Techniques Vref VO To Output Voltage of System Error Amp 3 1 Vref + – R2 – 2 Error Amp 3 VO = Vref Positive Output Voltage VO = Vref 1+ R1 Negative Output Voltage 2 R2 1 + R1 R1 R2 VO To Output Voltage of System R1 R2 Figure 16. Deadtime Control Circuit Figure 17. Soft–Start Circuit Output Control R1 Vref Output Q DT RT 4 Q CT 5 6 CS Vref Output 4 DT R2 RS 0.001 30k Max. % on Time, each output ≈ 45 – 80 1 + R1 R2 Figure 18. Output Connections for Single–Ended and Push–Pull Configurations C1 C1 QC Q1 2.4 V ≤ VOC ≤ Vref Q1 E1 Output Control 1.0 mA to 500 mA Single–Ended 8 Q2 E2 1.0 mA to 250 mA Output Control Push–Pull C2 C2 0 ≤ VOC ≤ 0.4 V E1 Q2 QE E2 1.0 mA to 250 mA MOTOROLA ANALOG IC DEVICE DATA TL594 Figure 19. Slaving Two or More Control Circuits Figure 20. Operation with Vin > 40 V Using External Zener Vref VCC RS 6 5 RT 12 Vin > 40V RT 1N975A Master VZ = 39V CT CT 5.0V Ref 270 Vref Gnd 7 6 RT 5 Slave (Additional Circuits) CT Figure 21. Pulse Width Modulated Push–Pull Converter +Vin = 8.0V to 20V 12 1 2 1.0M 33k 0.01 0.01 3 15 16 47 VCC + C1 – Tip 32 TL594 Comp – C2 + 8 T1 OC VREF DT CT RT Gnd E1 E2 14 4 5 6 7 9 10 + 11 Tip 32 10 10k 22 k L1 + + 50 25V 47 50 35V 4.7k + 50 35V 1.0 1N4934 13 4.7k 4.7k +VO = 28V IO = 0.2A 1N4934 240 15k 0.001 All capacitors in µF Test Conditions Results Line Regulation Vin = 10 V to 40 V 14 mV 0.28% Load Regulation Vin = 28 V, IO = 1.0 mA to 1.0 A 3.0 mV 0.06% Output Ripple Vin = 28 V, IO = 1.0 A 65 mVpp P.A.R.D. Short Circuit Current Vin = 28 V, RL = 0.1 Ω 1.6 A Efficiency Vin = 28 V, IO = 1.0 A 71% MOTOROLA ANALOG IC DEVICE DATA L1 – 3.5 mH @ 0.3 A T1 – Primary: 20T C.T. #28 AWG T1 – Secondary: 12OT C.T. #36 AWG T1 – Core: Ferroxcube 1408P–L00–3CB 9 TL594 Figure 22. Pulse Width Modulated Step–Down Converter 1.0mH @ 2.0A +Vin = 10V to 40V +VO = 5.0V Tip 32A IO = 1.0A 47 150 12 8 VCC 50 50V 47k 0.1 11 C1 C2 + TL594 CT RT 5 6 13 7 9 E2 3 – 2 + 1 Vref D.T. O.C. Gnd E1 4 Comp 1.0M 5.1k 5.1k 14 – 15 16 + MR850 5.1k 500 10V + + 10 50 10V 150 0.001 47k 0.1 Test 10 Conditions Results Line Regulation Vin = 8.0 V to 40 V 3.0 mV 0.01% Load Regulation Vin = 12.6 V, IO = 0.2 mA to 200 mA 5.0 mV 0.02% Output Ripple Vin = 12.6 V, IO = 200 mA Short Circuit Current Vin = 12.6 V, RL = 0.1 Ω Efficiency Vin = 12.6 V, IO = 200 mA 40 mVpp P.A.R.D. 250 mA 72% MOTOROLA ANALOG IC DEVICE DATA TL594 OUTLINE DIMENSIONS D SUFFIX PLASTIC PACKAGE CASE 751B–05 (SO–16) ISSUE J –A– 16 9 1 8 –B– P NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.127 (0.005) TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION. 8 PL 0.25 (0.010) M B S G R K F X 45 _ C –T– SEATING PLANE J M D 16 PL 0.25 (0.010) M T B A S S N SUFFIX PLASTIC PACKAGE CASE 648–08 ISSUE R –A– 16 9 1 8 C L S –T– SEATING PLANE K H G D J 16 PL 0.25 (0.010) MOTOROLA ANALOG IC DEVICE DATA M T A M MILLIMETERS MIN MAX 9.80 10.00 3.80 4.00 1.35 1.75 0.35 0.49 0.40 1.25 1.27 BSC 0.19 0.25 0.10 0.25 0_ 7_ 5.80 6.20 0.25 0.50 INCHES MIN MAX 0.386 0.393 0.150 0.157 0.054 0.068 0.014 0.019 0.016 0.049 0.050 BSC 0.008 0.009 0.004 0.009 0_ 7_ 0.229 0.244 0.010 0.019 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION L TO CENTER OF LEADS WHEN FORMED PARALLEL. 4. DIMENSION B DOES NOT INCLUDE MOLD FLASH. 5. ROUNDED CORNERS OPTIONAL. B F DIM A B C D F G J K M P R M DIM A B C D F G H J K L M S INCHES MIN MAX 0.740 0.770 0.250 0.270 0.145 0.175 0.015 0.021 0.040 0.70 0.100 BSC 0.050 BSC 0.008 0.015 0.110 0.130 0.295 0.305 0_ 10 _ 0.020 0.040 MILLIMETERS MIN MAX 18.80 19.55 6.35 6.85 3.69 4.44 0.39 0.53 1.02 1.77 2.54 BSC 1.27 BSC 0.21 0.38 2.80 3.30 7.50 7.74 0_ 10 _ 0.51 1.01 11 TL594 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. 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Box 20912; Phoenix, Arizona 85036. 1–800–441–2447 or 602–303–5454 JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315 MFAX: [email protected] – TOUCHTONE 602–244–6609 INTERNET: http://Design–NET.com ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 12 ◊ *TL594/D* MOTOROLA ANALOG IC DEVICE DATA TL594/D