TL1451AC, TL1451AY DUAL PULSE-WIDTH-MODULATION CONTROL CIRCUITS

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1 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Complete PWM Power Control Circuitry Completely Synchronized Operation Internal Undervoltage Lockout Protection Wide Supply Voltage Range Internal Short-Circuit Protection Oscillator Frequency...5 khz Max Variable Dead Time Provides Control Over Total Range Internal Regulator Provides a Stable.5-V Reference Supply CT RT ERROR IN + AMPLIFIER IN FEEDBACK DTC OUT GND DB, N, NS, OR PW PACKAGE (TOP VIEW) REF SCP IN + ERROR IN AMPLIFIER FEEDBACK DTC OUT V CC description The TL45AC incorporates on a single monolithic chip all the functions required in the construction of two pulse-width-modulation (PWM) control circuits. Designed primarily for power supply control, the TL45AC contains an on-chip.5-v regulator, two error amplifiers, an adjustable oscillator, two dead-time comparators, undervoltage lockout circuitry, and dual common-emitter output transistor circuits. The uncommitted output transistors provide common-emitter output capability for each controller. The internal amplifiers exhibit a common-mode voltage range from.4 V to.45 V. The dead-time control (DTC) comparator has no offset unless externally altered and can provide % to % dead time. The on-chip oscillator can be operated by terminating RT and CT. During low V CC conditions, the undervoltage lockout control circuit feature locks the outputs off until the internal circuitry is operational. The TL45AC is characterized for operation from C to 85 C. TA SMALL OUTLINE (DB) AVAILABLE OPTIONS PACKAGED DEVICES PLASTIC DIP (N) SMALL OUTLINE (NS) TSSOP (PW) CHIP FORM (Y) C to 85 C TL45ACDB TL45ACN TL45ACNS TL45ACPW TL45AY The DB and PW packages are only available left-end taped and reeled (add LE suffix, i.e., TL45ACPWLE). PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright 995, Texas Instruments Incorporated POST OFFICE BOX DALLAS, TEXAS

2 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 functional block diagram DTC VCC RT CT 9 4 ERROR IN + AMPLIFIER 3 IN FEEDBACK 5 FEEDBACK SCP 5 + / Vref kω Reference Voltage Oscillator PWM COMP OUTPUT 6 REF 7 kω UVLO R R S ERROR AMPLIFIER IN + IN OUTPUT PWM COMP DTC 6 8 GND COMPONENT COUNT Resistors 65 Capacitors 8 Transistors 5 JFETs 8 4 POST OFFICE BOX DALLAS, TEXAS 7565

3 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 TL45AY chip information This chip, when properly assembled, displays characteristics similar to the TL45AC. Thermal compression or ultrasonic bonding may be used on the doped aluminum bonding pads. The chip may be mounted with conductive epoxy or a gold-silicon preform. BONDING PAD ASSIGNMENTS () (9) (8) (7) () (6) 89 () (5) (3) (4) (4) (3) (5) (6) () () 75 CT RT IN+ IN FEEDBACK DTC OUT GND () () (3) (4) (5) (6) (7) (8) TL45Y (6) (5) (4) (3) () () () (9) REF SCP IN+ IN FEEDBACK DTC OUT VCC CHIP THICKNESS: 5 MILS TYPICAL BONDING PADS: 4 4 MILS MINIMUM TJmax = 5 C TOLERANCES ARE ±%. ALL DIMENSIONS ARE IN MILS. POST OFFICE BOX DALLAS, TEXAS

4 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 absolute maximum ratings over operating free-air temperature range Supply voltage, V CC V Amplifier input voltage, V I V Collector output voltage, V O V Collector output current, I O ma Continuous power total dissipation See Dissipation Rating Table Operating free-air temperature range, T A C to 85 C Storage temperature range, T stg C to 5 C Lead temperature,6 mm (/6 inch) from case for seconds C Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. PACKAGE TA 5 C POWER RATING DISSIPATION RATING TABLE DERATING FACTOR ABOVE TA = 7 C POWER RATING TA = 85 C POWER RATING DB 775 mw 6. mw/ C 496 mw 43 mw N mw 8. mw/ C 64 mw 5 mw NS 5 mw 4. mw/ C 3 mw 6 mw PW 7 mw 5.6 mw/ C 448 mw 364 mw recommended operating conditions MIN MAX UNIT Supply voltage, VCC V Amplifier input voltage, VI.5.45 V Collector output voltage, VO 5 V Collector output current, IO ma Current into feedback terminal 45 µa Feedback resistor, RF kω Timing capacitor, CT 5 5 pf Timing resistor, RT 5. kω Oscillator frequency 5 khz Operating free-air temperature, TA 85 C electrical characteristics over recommended operating free-air temperature range, V CC = 6 V, f = khz (unless otherwise noted) reference section PARAMETER TEST CONDITIONS TL45AC TL45Y MIN TYP MAX MIN TYP MAX Output voltage (pin 6) IO = ma V Output voltage change with temperature TA = C to 5 C.% ±%.% to 85 C.% ±%.% Input voltage regulation VCC = 3.6 V to 4 V.5 mv Output voltage regulation IO =. ma to ma 7.5 mv Short-circuit output current VO = 3 3 ma All typical values are at. UNIT 4 4 POST OFFICE BOX DALLAS, TEXAS 7565

5 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 undervoltage lockout section PARAMETER TEST CONDITIONS TL45AC, TL45AY MIN TYP MAX Upper threshold voltage (VCC).7 V Lower threshold voltage (VCC) Hysteresis (VCC) IO(ref) =ma. ma, TA=5 C UNIT.6 V 8 mv Reset threshold voltage (VCC).5.9 V All typical values are at. short-circuit protection control section PARAMETER TEST CONDITIONS TL45AC TL45AY MIN TYP MAX MIN TYP MAX Input threshold voltage (SCP) V Standby voltage (SCP) No pullup mv Latched input voltage (SCP) No pullup 6 6 mv Input (source) current VI =.7 V, 5 5 µa Comparator threshold voltage (FEEDBACK).8.8 V All typical values are at. oscillator section PARAMETER TEST CONDITIONS TL45C TL45AY MIN TYP MAX MIN TYP MAX Frequency CT = 33 pf, RT = kω khz Standard deviation of frequency CT = 33 pf, RT = kω % % Frequency change with voltage VCC = 3.6 V to 4 V % % Frequency change with temperature All typical values are at. dead-time control section PARAMETER TA = C to 5 C.4% ±%.4% to 85 C.% ±%.% TEST CONDITIONS TL45AC TL45AY MIN TYP MAX MIN TYP MAX Input bias current (DTC) µa Latch mode (source) current (DTC) µa Latched input voltage (DTC) IO = 4 µa.3 V Input threshold voltage at f = khz(dtc) All typical values are at. Zero duty cycle Maximum duty cycle UNIT UNIT UNIT V POST OFFICE BOX DALLAS, TEXAS

6 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 error-amplifier section PARAMETER TEST CONDITIONS TL45AC TL45AY MIN TYP MAX MIN TYP MAX Input offset voltage VO (FEEDBACK) =.5 V ±6 mv Input offset current VO (FEEDBACK) =.5 V ± na Input bias current VO (FEEDBACK) =.5 V na Common-mode input voltage range VCC = 3.6 V to 4 V Open-loop voltage amplification RF = kω db Unity-gain bandwidth.5.5 MHz Common-mode rejection ratio db Positive output voltage swing Vref. V Negative output voltage swing V Output (sink) current (FEEDBACK) VID =. V, VO =.5 V ma Output (source) current (FEEDBACK) VID =. V, VO =.5 V µa All typical values are at. output section PARAMETER TEST CONDITIONS.5 to.45 TL45AC TL45AY MIN TYP MAX MIN TYP MAX Collector off-state current VO = 5 V µa Output saturation voltage IO = ma.. V Short-circuit output current VO = 6 V 9 9 ma All typical values are at. UNIT V UNIT pwm comparator section PARAMETER Input threshold voltage at f = khz(feedback) All typical values are at. TL45AC TL45AY TEST CONDITIONS MIN TYP MAX MIN TYP MAX Zero duty cycle Maximum duty cycle UNIT V total device PARAMETER TEST CONDITIONS TL45AC TL45AY MIN TYP MAX MIN TYP MAX UNIT Standby supply current Off-state ma Average supply current RT = kω ma All typical values are at. 4 6 POST OFFICE BOX DALLAS, TEXAS 7565

7 PARAMETER MEASUREMENT INFORMATION SLVS4C FEBRUARY 983 REVISED OCTOBER 995 S Test Input RL CPE.47 µf 4.7 kω RL OUT 4.7 kω OUT TL55AC CT 33 pf RT kω Test Input Figure. Test Circuit Oscillator Triangle Waveform Error Amplifier Output Dead-Time Input Voltage Short-Circuit Protection Comparator Input Voltage PWM Comparator Output Voltage. V.6 V.4 V.5 V H L Dead Time % Output Transistor Collector Waveform H L Protection Enable Terminal Waveform Short-Circuit Protection Comparator Output t pe.6 V V H L Power Supply Voltage.8 V TYP 3.6 V V Protection Enable Time, tpe = (.5 x 6 x Cpe) in seconds Figure. TL45AC Timing Diagram POST OFFICE BOX DALLAS, TEXAS

8 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 f fosc Triangle Oscillator Frequency Hz M k k TRIANGLE OSCILLATOR FREQUENCY TIMING RESISTANCE CT = 5 pf CT = 5 pf CT = 5 pf k k 4 k k 4 k k 4 k M RT Timing Resistance Ω f afosc osc Oscillator Frequency Variation % 3 OSCILLATOR FREQUENCY VARIATION FREE-AIR TEMPERATURE VCC = 3.6 V RT = kω CT = 33 pf fosc = khz ÎÎ ÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎ ÎÎÎÎ ÎÎÎ ÎÎ ÎÎ TA Free-Air Temperature C Figure 3 Figure 4 Triangle Waveform Swing Voltage V TRIANGLE WAVEFORM SWING VOLTAGE TIMING CAPACITANCE RT = 5. kω Triangle Waveform Period µs us TRIANGLE WAVEFORM PERIOD TIMING CAPACITANCE RT = 5. kω CT Timing Capacitance pf CT Timing Capacitance pf Figure 5 Figure POST OFFICE BOX DALLAS, TEXAS 7565

9 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 V O(ref) avref Reference Output Voltage Variation mv REFERENCE OUTPUT VOLTAGE VARIATION FREE-AIR TEMPERATURE 3 VCC = 3.6 V II(ref) = ma ÎÎ ÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎ ÎÎÎÎÎ ÎÎ ÎÎÎ ÎÎ TA Free-Air Temperature C V O(ref) avref Reference Output Voltage Variation mv REFERENCE OUTPUT VOLTAGE VARIATION FREE-AIR TEMPERATURE 3 VCC = 4 V II(ref) = ma Î ÎÎÎÎÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎ Î ÎÎ Î TA Free-Air Temperature C Figure 7 Figure 8 V O(ref) Vref Reference Output Voltage V REFERENCE OUTPUT VOLTAGE SUPPLY VOLTAGE Dropout Voltage Variation V DROPOUT VOLTAGE VARIATION FREE-TEMPERATURE II(ref) = ma VCC Supply Voltage V TA Free-Air Temperature C Figure 9 Figure POST OFFICE BOX DALLAS, TEXAS

10 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 V VCE Output Collector Voltage V CE , 8 UNDERVOLTAGE LOCKOUT HYSTERESIS CHARACTERISTICS 5 V TA = 85 C RL I = IO VDE IO = ma 3 T A = C VCC Supply Voltage V 4 5 Undervoltage Lockout Threshold Voltage V UNDERVOLTAGE LOCKOUT CHARACTERISTIC Threshold Voltage VTH (Left Scale) Threshold Voltage VTL (Left Scale).5 Hysteresis Voltage (Right Scale).5 5 TA Free-Air Temperature C Undervoltage Lockout Hystersis Voltage mv Figure Figure SHORT-CIRCUIT PROTECTION CHARACTERISTICS.3 3 Comparator Threshold Voltage V.5..5 Short-Circuit Protection Latch Reset Supply Voltage (Right Scale) Short-Circuit Protection Comparator Threshold Voltage (Left Scale).5.5 RS Latch Reset Supply Voltage V TA Free-Air Temperature C Figure 3 4 POST OFFICE BOX DALLAS, TEXAS 7565

11 SLVS4C FEBRUARY 983 REVISED OCTOBER PROTECTION ENABLE TIME PROTECTION ENABLE CAPACITANCE tpe Protection Enable Time s CPE Protection Enable Capacitance µf SCP Vref kω Vref Vref ERROR AMP ERROR AMP Short-circuit Protection Comparator kω CPE S R Protection Latch U.V.L.O..5 V + Figure 4 POST OFFICE BOX DALLAS, TEXAS

12 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Error Amp Maximum Output Voltage Swing V ERROR AMP MAXIMUM OUTPUT VOLTAGE SWING FREQUENCY k k k M M f Frequency Hz Open-Loop Voltage Amplification db OPEN-LOOP VOLTAGE AMPLIFICATION FREQUENCY k k k M M f Frequency Hz Figure 5 Figure 6 5 GAIN (AMPLIFIER IN UNITY-GAIN CONFIGURATION) FREQUENCY G Gain db 5 5 k k k f Frequency Hz M M Figure 7 4 POST OFFICE BOX DALLAS, TEXAS 7565

13 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Closed-Loop Gain db Rref = 5 Ω Cref = 47 pf CLOSED-LOOP GAIN AND PHASE SHIFT FREQUENCY Closed-Loop Gain (Left Scale) CX: Phase Shift (Right Scale) 47 pf 47 pf 47 pf 8 9 k k k M f Frequency Hz Phase Shift Vref + 39 kω Cx Rref 39 kω Cref Test Circuit Figure 8 POST OFFICE BOX DALLAS, TEXAS

14 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Closed-Loop Gain db Rref = 5 Ω Cref = 47 pf CLOSED-LOOP GAIN AND PHASE SHIFT FREQUENCY Closed-Loop Gain (Left Scale) Phase Shift (Right Scale) CX: 47 pf 47 pf 47 pf 8 9 k k k M f Frequency Hz Phase Shift 39 kω Vref Cx + Rref 39 kω Cref Test Circuit Figure POST OFFICE BOX DALLAS, TEXAS 7565

15 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Closed-Loop Gain db Rref = 5 Ω Cref = 47 pf CLOSED-LOOP GAIN AND PHASE SHIFT FREQUENCY Closed-Loop Gain (Left Scale) CX: Phase Shift (Right Scale) 47 pf 47 pf 47 pf 8 9 k k k M f Frequency Hz Phase Shift 39 kω Vref Cx + Rref 39 kω Cref Test Circuit Figure POST OFFICE BOX DALLAS, TEXAS

16 SLVS4C FEBRUARY 983 REVISED OCTOBER Cref = 47 pf CLOSED-LOOP GAIN AND PHASE SHIFT FREQUENCY Closed-Loop Gain db Closed-Loop Gain (Left Scale) Phase Shift (Right Scale) 8 9 k k k M f Frequency Hz Phase Shift 39 kω Vref + 39 kω Cref Test Circuit Figure 4 6 POST OFFICE BOX DALLAS, TEXAS 7565

17 OUTPUT SINK CURRENT COLLECTOR OUTPUT SATURATION VOLTAGE TA = C SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Output Sink Current ma TA = 85 C VCC = 3.6 V 5 5 Collector Output Saturation Voltage V Figure VO(ref). MAXIMUM OUTPUT VOLTAGE SWING FREE-AIR TEMPERATURE Vref V OM Maximum Output Voltage Swing V VO(ref). VO(ref).3 VO(ref).4 VO(ref).5 VO(ref).6 Maximum Output Voltage Swing (Right Scale) Maximum Output Voltage Swing (Right Scale) VO(ref) TA Free-Air Temperature C V OM Maximum Output Voltage Swing V 33 kω 33 kω Vvom + RL kω VCC = 3.6 V RL = kω VOM+ =.5 V VOM =.5 V (Right Scale) VOM =.35 V (Left Scale) TEST CIRCUIT Figure 3 POST OFFICE BOX DALLAS, TEXAS

18 SLVS4C FEBRUARY 983 REVISED OCTOBER 995 Output Transistor On Duty Cycle % OUTPUT TRANSISTOR ON DUTY CYCLE DEAD-TIME INPUT VOLTAGE VCC = 3.6 V RT = kω CT = 33 pf ICC (Standby) Standby Current ma STANDBY CURRENT SUPPLY VOLTAGE Dead-Time Input Voltage V VCC Supply Voltage V Figure 4 Figure 5 ICC Supply Current ma STANDBY CURRENT FREE-AIR TEMPERATURE Average Supply Current VCC = 6 V, RT = kω, CT = 33 pf Stand-By Current, VCC = 4 V, No Load Stand-By Current, VCC = 3.6 V, No Load TA Free-Air Temperature C 75 Maximum Continuous Power Dissipation mw MAXIMUM CONTINUOUS POWER DISSIPATION FREE-AIR TEMPERATURE Pin N Plastic Dip 6-Pin NS Plastic SO Thermal Resistance 5 C/W Thermal Resistance 5 C/W TA Free-Air Temperature Figure 6 Figure POST OFFICE BOX DALLAS, TEXAS 7565

19 APPLICATION INFORMATION SLVS4C FEBRUARY 983 REVISED OCTOBER 995 VCC kω 47 Ω 5 Ω L.47 µf 5 kω 33 kω 33 pf 33 kω R R R3 C Step-Up Output 33 kω 33 kω R4 Vref C 5 pf TL45AC Ω 47 Ω C5 R5 5 pf Ω µf L 33 kω 33 kω 47 Ω R6 R7 C4 Step-Down Output NOTE A. Values for R through R7, C through C4, and L and L depend upon individual application. Figure 8. High-Speed Dual Switching Regulator POST OFFICE BOX DALLAS, TEXAS

20 4 POST OFFICE BOX DALLAS, TEXAS 7565

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