TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 D D D D D D D KC PACKAGE (TOP VIEW) Output Adjustable From 1.25 V to 125 V When Used With an External Resistor Divider 700-mA Output Current Full Short-Circuit, Safe-Operating-Area, and Thermal-Shutdown Protection 0.001%/V Typical Input Voltage Regulation 0.15% Typical Output Voltage Regulation 76-dB Typical Ripple Rejection Standard TO-220AB Package IN OUT ADJ The OUT terminal is in electrical contact with the mounting base. TO-220AB I O A description The TL783 is an adjustable three-terminal high-voltage regulator with an output range of 1.25 V to 125 V and a DMOS output transistor capable of sourcing more than 700 mA. It is designed for use in high-voltage applications where standard bipolar regulators cannot be used. Excellent performance specifications, superior to those of most bipolar regulators, are achieved through circuit design and advanced layout techniques. As a state-of-the-art regulator, the TL783 combines standard bipolar circuitry with high-voltage double-diffused MOS transistors on one chip to yield a device capable of withstanding voltages far higher than standard bipolar integrated circuits. Because of its lack of secondary-breakdown and thermal-runaway characteristics usually associated with bipolar outputs, the TL783 maintains full overload protection while operating at up to 125 V from input to output. Other features of the device include current limiting, safe-operating-area (SOA) protection, and thermal shutdown. Even if ADJ is inadvertently disconnected, the protection circuitry remains functional. Only two external resistors are required to program the output voltage. An input bypass capacitor is necessary only when the regulator is situated far from the input filter. An output capacitor, although not required, improves transient response and protection from instantaneous output short circuits. Excellent ripple rejection can be achieved without a bypass capacitor at the adjustment terminal. The TL783C is characterized for operation over the virtual junction temperature range of 0°C to 125°C. AVAILABLE OPTIONS PACKAGED DEVICE TJ HEAT-SINK MOUNTED (KC) 0°C to 125°C TL783CKC CHIP FORM (Y) TL783Y Chip forms are tested at 25°C. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Copyright 2000, Texas Instruments Incorporated 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. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 functional block diagram VI – Error Amplifier IN VO [V + ǒ) Ǔ ref 1 R2 R1 VO OUT Protection Circuit Vref R1 ADJ R2 absolute maximum ratings over operating temperature range (unless otherwise noted)† Input-to-output differential voltage, Vl – VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 V Operating free-air, TA; case, TC; or virtual junction, TJ, temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C Package thermal impedance, θJA (see Notes 1 and 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22°C/W Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°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. NOTES: 1. Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable ambient temperature is PD = (TJ(max) – TA)/θJA. Operating at the absolute maximum TJ of 150°C can impact reliability. Due to variations in individual device electrical characteristics and thermal resistance, the built-in thermal overload protection may be activated at power levels slightly above or below the rated dissipation. 2. The package thermal impedance is calculated in accordance with JESD 51. recommended operating conditions MIN MAX UNIT 125 V 15 700 mA 0 125 °C Input-to-output voltage differential, VI – VO Output current, IO Operating virtual junction temperature, TJ 2 TL783C POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 electrical characteristics at Vl – VO = 25 V, IO = 0.5 A, TJ = 0°C to 125°C (unless otherwise noted) TL783C TEST CONDITIONS† PARAMETER MIN TYP MAX 0.001 0.01 0.004 0.02 Input voltage g regulation‡ VI – VO = 20 V to 125 V V, P ≤ rated dissipation TJ = 25°C TJ = 0°C to 125°C Ripple rejection ∆VI(PP) = 10 V, VO = 10 V, f = 120 Hz IO = 15 mA to 700 mA mA, TJ = 25°C VO ≤ 5 V VO ≥ 5 V 7.5 25 0.15% 0.5% IO = 15 mA to 700 mA mA, P ≤ rated dissipation VO ≤ 5 V VO ≥ 5 V 20 70 0.3% 1.5% Output voltage g regulation 66 Output voltage change with temperature %/V dB mV mV 0.4% Output voltage long-term drift 1000 hours at TJ = 125°C, VI – VO = 125 V Output noise voltage f = 10 Hz to 10 kHz, TJ = 25°C Minimum output current to maintain regulation VI – VO = 125 V Peak output current 76 UNIT 0.2% 0.003% 15 VI – VO = 25 V, VI – VO = 15 V, t = 1 ms VI – VO = 25 V, VI – VO = 125 V, t = 30 ms 700 900 t = 30 ms 100 250 mA 1100 t = 30 ms 715 ADJ input current Change in ADJ input current VI – VO = 15 V to 125 V, IO = 15 mA to 700 mA, P ≤ rated dissipation Reference voltage (OUT to ADJ) VI – VO = 10 V to 125 V, See Note 3 IO = 15 mA to 700 mA, P ≤ rated dissipation, 1.2 mA 83 110 µA 0.5 5 µA 1.27 1.3 V † Pulse-testing techniques maintain the junction temperature as close to the ambient temperature as possible. Thermal effects must be taken into account separately. ‡ Input voltage regulation is expressed here as the percentage change in output voltage per 1-V change at the input. NOTE 3: Due to the dropout voltage and output current-limiting characteristics of this device, output current is limited to less than 700 mA at input-to-output voltage differentials of less than 25 V. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 electrical characteristics at Vl – VO = 25 V, IO = 0.5 A, TJ = 25°C (unless otherwise noted) Input voltage regulation‡ VI – VO = 20 V to 125 V, P ≤ rated dissipation Ripple rejection ∆VI(PP) = 10 V, VO = 10 V, Output voltage g regulation TL783Y TEST CONDITIONS† PARAMETER MIN 0.001 Peak output current MAX UNIT %/V f = 120 Hz 76 dB IO = 15 mA to 700 mA VO ≤ 5 V VO ≥ 5 V 7.5 mV IO = 15 mA to 700 mA mA, VO ≤ 5 V VO ≥ 5 V P ≤ rated dissipation Output voltage change with temperature Output noise voltage TYP 0.15% 20 mV 0.3% 0.4% f = 10 Hz to 10 kHz 0.003% VI – VO = 25 V, VI – VO = 15 V, t = 1 ms 1100 t = 30 ms 715 VI – VO = 25 V, VI – VO = 125 V, t = 30 ms 900 t = 30 ms 250 ADJ input current Change in ADJ input current VI – VO = 15 V to 125 V, IO = 15 mA to 700 mA, P ≤ rated dissipation Reference voltage (OUT to ADJ) VI – VO = 10 V to 125 V, See Note 3 IO = 15 mA to 700 mA, P ≤ rated dissipation, mA 83 µA 0.5 µA 1.27 V † Pulse-testing techniques maintain the junction temperature as close to the ambient temperature as possible. Thermal effects must be taken into account separately. ‡ Input voltage regulation is expressed here as the percentage change in output voltage per 1-V change at the input. NOTE 3: Due to the dropout voltage and output current-limiting characteristics of this device, output current is limited to less than 700 mA at input-to-output voltage differentials of less than 25 V. 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 TYPICAL CHARACTERISTICS OUTPUT CURRENT LIMIT vs INPUT-TO-OUTPUT VOLTAGE DIFFERENTIAL OUTPUT CURRENT LIMIT vs INPUT-TO-OUTPUT VOLTAGE DIFFERENTIAL 2 1.8 ÎÎÎÎ ÎÎÎÎÎ 2 tw = 1 ms 1.6 1.4 Output Current Limit – A Output Current Limit – A 1.6 ÎÎÎÎ ÎÎÎÎ 1.2 TC = 0°C 1 ÎÎÎÎ ÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ 0.8 0.6 TC = 25°C 0.4 0 0 25 50 1.4 TC = 0°C 1 0.8 TC = 25°C 0.6 TC = 125°C 0.2 0 75 100 0 125 25 50 75 100 Figure 1 Figure 2 OUTPUT CURRENT LIMIT vs TIME RIPPLE REJECTION vs OUTPUT VOLTAGE ÎÎÎÎÎ ÎÎÎÎÎ 1.6 120 VI – VO = 25 V TC = 25°C 1.4 125 VI – VO – Input-to-Output Voltage Differential – V VI – VO – Input-to-Output Voltage Differential – V 100 1.2 Ripple Rejection – dB Output Current Limit – A ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ 1.2 0.4 TC = 125°C 0.2 tw = 30 ms 1.8 1 0.8 0.6 0.4 80 60 ÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎ VI(AV) – VO = 25 V ∆VI(PP) = 10 V IO = 100 mA f = 120 Hz Co = 0 TJ = 25°C 40 20 0.2 0 0 0 10 20 30 40 0 10 20 30 40 50 60 70 80 90 100 VO – Output Voltage – V Time – ms Figure 3 Figure 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 TYPICAL CHARACTERISTICS† RIPPLE REJECTION vs OUTPUT CURRENT RIPPLE REJECTION vs FREQUENCY 100 90 100 Ripple Rejection – dB Ripple Rejection – dB 80 80 60 ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ VI(AV) = 25 V ∆VI(PP) = 10 V VO = 10 V f = 120 Hz Co = 0 TJ = 25°C 40 20 100 200 300 50 40 600 700 ÎÎÎÎÎ ÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ Co = 0 30 10 400 500 Co = 10 µF 60 20 VI(AV) = 25 V ∆VI(PP) = 10 V VO = 10 V IO = 500 mA TJ = 25°C 0 0.01 0 0 ÎÎÎÎ 70 800 0.1 1 REFERENCE VOLTAGE vs VIRTUAL JUNCTION TEMPERATURE OUTPUT IMPEDANCE vs FREQUENCY ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ 1.30 VI = 35 V VO = 10 V IO = 500 mA TJ = 25°C 1.29 V ref – Reference Voltage – V Zo – Output Impedance – Ω 1 1000 Figure 6 Figure 5 101 100 f – Frequency – kHz IO – Output Current – mA 102 10 10–1 10–2 ÎÎÎÎ ÎÎÎÎ VI = 20 V IO = 15 mA 1.28 1.27 1.26 1.25 1.24 10–3 1.23 10–4 101 102 103 104 105 106 107 f – Frequency – kHz 1.22 –75 –50 –25 0 25 50 75 100 125 150 175 TJ – Virtual Junction Temperature – °C Figure 8 Figure 7 † Data at high and low temperatures are applicable only within the recommended operating free-air temperature ranges of the various devices. 6 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 TYPICAL CHARACTERISTICS DROPOUT VOLTAGE vs VIRTUAL JUNCTION TEMPERATURE INPUT CURRENT AT ADJ vs VIRTUAL JUNCTION TEMPERATURE 25 90 VI = 25 V VO = Vref IO = 500 mA 20 Dropout Voltage – V ADJ Input Current – µ A 88 86 84 82 80 0 ∆VO = 100 mV 25 50 100 75 125 15 10 IO = 700 mA IO = 600 mA IO = 500 mA 5 IO = 250 mA IO = 100 mA IO = 15 mA 0 –75 –50 –25 0 25 75 50 100 125 TJ – Virtual Junction Temperature – °C TJ – Virtual Junction Temperature – °C Figure 9 Figure 10 OUTPUT CURRENT† vs INPUT VOLTAGE OUTPUT VOLTAGE DEVIATION vs VIRTUAL JUNCTION TEMPERATURE 12 VI = 25 V VO = 5 V IO = 15 mA to 700 mA –0.1 TC = 0°C 10 I O – Output Current – mA ∆VO – Output Voltage Deviation – % 0 –0.2 –0.3 8 TC = 25°C 6 TC = 125°C 4 2 –0.4 0 0 –0.5 0 25 50 75 100 125 150 TJ – Virtual Junction Temperature – °C 25 50 75 100 125 VI – Input Voltage – V † This is the minimum current required to maintain voltage regulation. Figure 11 Figure 12 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 ∆ VO – Output Voltage Deviation – V LINE TRANSIENT RESPONSE ÎÎÎÎ ÎÎÎ ÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ TJ = 25°C 0.4 0.2 0 Co = 0 Co = 10 µF –0.2 1 0.5 0 0 1 2 3 4 Time – µs I O – Output Current – A Change in Input Voltage – V ∆ VO – Output Voltage Deviation – V TYPICAL CHARACTERISTICS LOAD TRANSIENT RESPONSE 6 4 2 0 –2 –4 –6 0.8 VI = 35 V VO = 10 V Co = 1 µF TJ = 25°C 0.6 0.4 0.2 0 0 Figure 13 40 80 120 160 200 240 Time – µs Figure 14 DESIGN CONSIDERATIONS The internal reference (see functional block diagram) generates 1.25 V nominal (Vref) between OUT and ADJ. This voltage is developed across R1 and causes a constant current to flow through R1 and the programming resistor R2, giving an output voltage of: VO = Vref (1 + R2/R1) + lI(ADJ) (R2) or VO ≈ Vref (1 + R2/R1) The TL783 was designed to minimize the input current at ADJ and maintain consistency over line and load variations, thereby minimizing the associated (R2) error term. To maintain II(ADJ) at a low level, all quiescent operating current is returned to the output terminal. This quiescent current must be sunk by the external load and is the minimum load current necessary to prevent the output from rising. The recommended R1 value of 82 Ω provides a minimum load current of 15 mA. Larger values can be used when the input-to-output differential voltage is less than 125 V (see the output-current curve in Figure 14) or when the load sinks some portion of the minimum current. 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 DESIGN CONSIDERATIONS bypass capacitors The TL783 regulator is stable without bypass capacitors; however, any regulator becomes unstable with certain values of output capacitance if an input capacitor is not used. Therefore, the use of input bypassing is recommended whenever the regulator is located more than four inches from the power-supply filter capacitor. A 1-µF tantalum or aluminum electrolytic capacitor usually is sufficient. Adjustment-terminal capacitors are not recommended for use on the TL783 because they can seriously degrade load transient response as well as create a need for extra protection circuitry. Excellent ripple rejection presently is achieved without this added capacitor. Due to the relatively low gain of the MOS output stage, output voltage dropout may occur under large load transient conditions. The addition of an output bypass capacitor greatly enhances load transient response and prevents dropout. For most applications, it is recommended that an output bypass capacitor be used, with a minimum value of: Co (µF) = 15/VO Larger values provide proportionally better transient-response characteristics. protection circuitry The TL783 regulator includes built-in protection circuits capable of guarding the device against most overload conditions encountered in normal operation. These protective features are current limiting, safe-operating-area protection, and thermal shutdown. These circuits protect the device under occasional fault conditions only. Continuous operation in the current limit or thermal shutdown mode is not recommended. The internal protection circuits of the TL783 protect the device up to maximum-rated VI as long as certain precautions are taken. If Vl is instantaneously switched on, transients exceeding maximum input ratings may occur, which can destroy the regulator. These are usually caused by lead inductance and bypass capacitors causing a ringing voltage on the input. In addition, when rise times in excess of 10 V/ns are applied to the input, a parasitic npn transistor in parallel with the DMOS output can be turned on, causing the device to fail. If the device is operated over 50 V and the input is switched on rather than ramped on, a low-Q capacitor, such as tantalum or aluminum electrolytic should be used rather than ceramic, paper, or plastic bypass capacitors. A Q factor of 0.015 or greater usually provides adequate damping to suppress ringing. Normally, no problems occur if the input voltage is allowed to ramp upward through the action of an ac line rectifier and filter network. Similarly, when an instantaneous short circuit is applied to the output, both ringing and excessive fall times can result. A tantalum or aluminum electrolytic bypass capacitor is recommended to eliminate this problem. However, if a large output capacitor is used and the input is shorted, addition of a protection diode may be necessary to prevent capacitor discharge through the regulator. The amount of discharge current delivered is dependent on output voltage, size of capacitor, and fall time of Vl. A protective diode (see Figure 17) is required only for capacitance values greater than: Co (µF) = 3 x 104/(VO)2 Care always should be taken to prevent insertion of regulators into a socket with power on. Power should be turned off before removing or inserting regulators. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 9 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 DESIGN CONSIDERATIONS TL783 VI IN OUT VO ADJ R1 Co R2 Figure 15. Regulator With Protective Diode load regulation The current-set resistor (R1) should be located close to the regulator output terminal rather than near the load. This eliminates long line drops from being amplified, through the action of R1 and R2, to degrade load regulation. To provide remote ground sensing, R2 should be near the load ground. TL783 VI IN VO Rline OUT ADJ RL R1 R2 Figure 16. Regulator With Current-Set Resistor 10 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 APPLICATION INFORMATION VI = 145 to 200 V 7.5 kΩ, 1 W TL783 VI = 125 V IN VO +V ref R2 R1 1 120 V, 1.5 W IN OUT ADJ OUT R1 82 Ω ADJ + + 1 µF† ǒ) Ǔ TIP150 10 µF 0.1 µF TL783 R2 0 to 8 kΩ 125 V R1 82 Ω + 10 µF R2 8.2 kΩ, 2W † Needed if device is more than 4 inches from filter capacitor Figure 17. 1.25-V to 115-V Adjustable Regulator Figure 18. 125-V Short-Circuit-Protected Off-Line Regulator 125 V 1Ω VI = 70 to 125 V 10 Ω 10 Ω TIP30C TIPL762 1 kΩ TIPL762 1 kΩ TL783 TL783 VO = 50 V at 0.5 A 10 kΩ IN OUT 10 kΩ IN OUT ADJ ADJ 82 Ω + R1 82 Ω VO + +V ref ǒ) Ǔ 1 R2 R1 50 µF 50 µF R2 3.3 kΩ, 1W Figure 19. 50-V Regulator With Current Boost POST OFFICE BOX 655303 Figure 20. Adjustable Regulator With Current Boost and Current Limit • DALLAS, TEXAS 75265 11 TL783 HIGH-VOLTAGE ADJUSTABLE REGULATOR SLVS036E – SEPTEMBER 1981 – REVISED FEBRUARY 2000 APPLICATION INFORMATION VI VI Load I TL783 1 µF + VR IN ref OUT ADJ TL783 R IN OUT I ADJ R + VR ref Load Figure 21. Current-Sinking Regulator VCC Figure 22. Current-Sourcing Regulator VI = 90 V TL783 IN TL783 1 µF OUT IN ADJ OUT 6.25 Ω OUTPUT ADJ 82 Ω TL783 IN OUT R2 V+ ADJ 82 Ω 48 V – + INPUT V– TL081 V OFFSET +V ref ǒ) Ǔ I R2 82 Figure 23. High-Voltage Unity-Gain Offset Amplifier 12 3.9 kΩ POST OFFICE BOX 655303 Figure 24. 48-V, 200-mA Float Charger • DALLAS, TEXAS 75265 IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. 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