TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 D D D D D D D D D D D Dual Output Voltages for Split-Supply Applications Output Current Range of 0 mA to 1.0 A Per Regulator 3.3-V/2.5-V, 3.3-V/1.8-V, and 3.3-V/Adjustable Output Fast-Transient Response 2% Tolerance Over Load and Temperature Dropout Voltage Typically 350 mV at 1 A Ultra Low 85 µA Typical Quiescent Current 1 µA Quiescent Current During Shutdown Dual Open Drain Power-On Reset With 200-ms Delay for Each Regulator 28-Pin PowerPAD TSSOP Package Thermal Shutdown Protection for Each Regulator PWP PACKAGE (TOP VIEW) NC NC 1GND 1EN 1IN 1IN NC NC 2GND 2EN 2IN 2IN NC NC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 1RESET NC NC 1FB/NC 1OUT 1OUT 2RESET NC NC NC 2OUT 2OUT NC NC NC – No internal connection description The TPS767D3xx family of dual voltage regulators offers fast transient response, low dropout voltages and dual outputs in a compact package and incorporating stability with 10-µF low ESR output capacitors. DROPOUT VOLTAGE vs FREE-AIR TEMPERATURE LOAD TRANSIENT RESPONSE 103 VO = 3.3 V CL =100 µF TA = 25°C 50 IO = 1 A VDO – Dropout Voltage – mV I O – Output Current – A ∆ VO – Change in Output Voltage – mV 100 0 –50 –100 1 0.5 0 102 101 IO = 10 mA 100 10–1 VO = 3.3 V CO = 10 µF 0 20 40 60 80 100 120 140 160 180 200 t – Time – µs 10–2 –60 –40 –20 IO = 0 0 20 40 60 80 100 120 140 TA – Free-Air Temperature – °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. PowerPAD is a trademark of Texas Instruments Incorporated. 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 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 description (continued) The TPS767D3xx family of dual voltage regulators is designed primarily for DSP applications. These devices can be used in any mixed-output voltage application, with each regulator supporting up to 1 A. Dual active-low reset signals allow resetting of core-logic and I/O separately. Because the PMOS device behaves as a low-value resistor, the dropout voltage is very low (typically 350 mV at an output current of 1 A for the TPS767D325) and is directly proportional to the output current. Additionally, since the PMOS pass element is a voltage-driven device, the quiescent current is very low and independent of output loading (typically 85 µA over the full range of output current, 0 mA to 1 A). These two key specifications yield a significant improvement in operating life for battery-powered systems. This LDO family also features a sleep mode; applying a TTL high signal to EN (enable) shuts down the regulator, reducing the quiescent current to 1 µA at TJ = 25°C. The RESET output of the TPS767D3xx initiates a reset in microcomputer and microprocessor systems in the event of an undervoltage condition. An internal comparator in the TPS767D3xx monitors the output voltage of the regulator to detect an undervoltage condition on the regulated output voltage. The TPS767D3xx is offered in 1.8-V, 2.5-V, and 3.3-V fixed-voltage versions and in an adjustable version (programmable over the range of 1.5 V to 5.5 V). Output voltage tolerance is specified as a maximum of 2% over line, load, and temperature ranges. The TPS767D3xx family is available in 28 pin PWP TSSOP package. They operate over a junction temperature range of –40°C to 125°C. AVAILABLE OPTIONS TA – 40°C to 125°C REGULATOR 1 VO (V) REGULATOR 2 VO (V) TSSOP (PWP) Adj (1.5 – 5.5 V) 3.3 V TPS767D301PWP 1.8 V 3.3 V TPS767D318PWP 2.5 V 3.3 V TPS767D325PWP The TPS767D301 is adjustable using an external resistor divider (see application information). The PWP packages are available taped and reeled. Add an R suffix to the device type (e.g., TPS767D301PWPR). TPS767D3xx VI 5 6 C1 0.1 µF 50 V IN RESET RESET 250 kΩ IN OUT 4 28 EN OUT GND 24 VO 23 + CO 10 µF 3 Figure 1. Typical Application Circuit (Fixed Versions) for Single Channel 2 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 functional block diagram—adjustable version (for each LDO) IN EN RESET _ + OUT + _ 200 ms Delay R1 Vref = 1.1834 V R2 GND functional block diagram—fixed-voltage version (for each LDO) IN EN RESET _ + OUT + _ 200 ms Delay Vref = 1.1834 V R1 FB/NC R2 GND External to the device POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 Terminal Functions TERMINAL NAME 1GND I/O NO. 3 DESCRIPTION Regulator #1 ground 1EN 4 I Regulator #1 enable 1IN 5, 6 I Regulator #1 input supply voltage 2GND 9 Regulator #2 ground 2EN 10 I Regulator #2 enable 2IN 11, 12 I Regulator #2 input supply voltage 2OUT 17, 18 O Regulator #2 output voltage 22 O Regulator #2 reset signal 23, 24 O Regulator #1 output voltage 2RESET 1OUT 1FB/NC 25 I Regulator #1 output voltage feedback for adjustable and no connect for fixed output 1RESET 28 O Regulator #1 reset signal NC 1, 2, 7, 8, 13–16, 19, 20, 21, 26, 27 No connection timing diagram VI Vres† Vres t VO VIT +‡ VIT +‡ Threshold Voltage VIT – Less than 5% of the output voltage VIT – t RESET Output Output Undefined ÎÎ ÎÎ ÎÎ ÎÎ 200 ms Delay 200 ms Delay ÎÎ ÎÎ ÎÎ ÎÎ Output Undefined t † Vres is the minimum input voltage for a valid RESET. The symbol Vres is not currently listed within EIA or JEDEC standards for semiconductor symbology. ‡ VIT –Trip voltage is typically 5% lower than the output voltage (95%VO) 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 absolute maximum ratings over operating free-air temperature (unless otherwise noted)† Input voltage range‡, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to 13.5 V Input voltage range, VI (1IN, 2IN, EN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to VI + 0.3 V Output voltage, VO (1OUT, 2OUT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V Output voltage, VO (RESET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16.5 V Peak output current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally limited ESD rating, HBM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 kV Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See dissipation rating tables Operating virtual junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 40°C to 125°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. ‡ All voltage values are with respect to network terminal ground. ÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁÁ DISSIPATION RATING TABLE PACKAGE PWP† AIR FLOW (CFM) TA ≤ 25°C POWER RATING DERATING FACTOR ABOVE TA = 25°C TA = 70°C POWER RATING TA = 85°C POWER RATING 0 3.58 W 35.8 mW/°C 1.97 W 1.43 W 250 5.07 W 50.7 mW/°C 2.79 W 2.03 W † This parameter is measured with the recommended copper heat sink pattern on a 4–layer PCB, 1 oz. copper on 4–in x 4–in ground layer. For more information, refer to TI technical brief literature number SLMA002. recommended operating conditions Input voltage, VI# (1IN, 2IN) Output current for each LDO, IO (Note 1) Output voltage range, VO (1OUT, 2OUT) MIN MAX 2.7 10 UNIT V 0 1.0 A 1.5 5.5 V Operating virtual junction temperature, TJ – 40 125 °C # To calculate the minimum input voltage for your maximum output current, use the following equation: VI(min) = VO(max) + VDO(max load). NOTE 1: Continuous current and operating junction temperature are limited by internal protection circuitry, but it is not recommended that the device operate under conditions beyond those specified in this table for extended periods of time. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 electrical characteristics, Vi = VO(nom) + 1 V, IO = 1 mA, EN = 0, CO = 10 µF(unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 1.5 V ≤ VO ≤ 5.5 V,, 10 µA < IO < 1 A TJ = 25°C TJ = –40°C to 125°C 1 8 V Ouput 1.8 2.8 V < VI < 10 V,, 10 µA < IO < 1 A TJ = 25°C TJ = –40°C to 125°C 1.764 2 5 V Output 2.5 3.5 V < VI < 10 V,, 10 µA < IO < 1 A TJ = 25°C TJ = –40°C to 125°C 2.45 3 3 V Output 3.3 4.3 V < VI < 10 V,, 10 µA < IO < 1 A TJ = 25°C TJ = –40°C to 125°C 3.234 10 µA < IO < 1 A, TJ = 25°C IO = 1 A, TJ = –40°C to 125°C Output voltage line regulation for each LDO (∆VO/VO) (see Notes 2 and 3) VO + 1 V < VI ≤ 10 V, TJ = 25°C 0.01 %/V Output noise voltage BW = 300 Hz to 50 kHz, CO = 10 µF, TJ = 25°C 190 µVrms Output current Limit for each LDO VO = 0 V Adjustable Output voltage g ((VO) (see Note 2) Quiescent current (GND current) for each LDO (see Note 2) VO 0.98VO 1.02VO 1.8 1.836 2.5 2.55 3.3 3.366 85 1.7 Standby current for each LDO FB input current Adjustable EN = VI, 2.7 < VI < 10V, TJ = –40°C to 125°C EN = VI, FB = 1.5 V 1 µA 2 Trip threshold voltage VO decreasing Hysteresis voltage Measured at VO Output low voltage VI = 2.7 V, Leakage current V(RESET) = 7 V V CO = 10 µF dB 1.1 V 98 0.5 0.15 RESET time-out delay 200 NOTES: 2. Minimum IN operating voltage is 2.7 V or VO(typ) + 1 V, whichever is greater. maximum IN voltage 10V. 3. If VO ≤ 1.8 V, Vimin = 2.7 V, and Vimax = 10 V: Line Reg. (mV) + ǒ%ńVǓ V O If VO ≥ 2.5 V, Vimin = Vo + 1 V, and Vimax = 10 V: Line Reg. (mV) + ǒ%ńVǓ V POST OFFICE BOX 655303 O ǒ V ǒ * 2.7 V imax 100 V imax * ǒ V O Ǔ 1000 )1 V 100 • DALLAS, TEXAS 75265 ǓǓ 1000 V 60 92 IO(RESET) = 1 mA µA nA 0.8 Minimum input voltage for valid RESET A °C 2.0 Power supply ripple rejection (see Note 2) 6 2 150 Low level enable input voltage Reset µA 10 High level enable input voltage f = 1 KHz, TJ = 25°C, IO(RESET) = 300µA V 125 Thermal shutdown juction temperature 2.7 < VI < 10V, TJ = 25°C, V %VO %VO 0.4 V 1 µA mA TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 electrical characteristics, Vi = VO(nom) + 1 V, IO = 1 mA, EN = 0, CO = 10 µF(unless otherwise noted) (continued) PARAMETER Input current (EN) MIN TYP MAX EN = 0 V TEST CONDITIONS –1 0 1 EN = VI –1 Load regulation Dropout voltage (see Note 4) UNIT µA 1 3 VO = 3.3 V,, IO = 1 A TJ = 25°C TJ = –40°C to 125°C mV 350 mV 575 NOTE 4: IN voltage equals Vo(Typ) – 100mV; Adjustable output voltage set to 3.3V nominal with external resistor divider. 1.8V, and 2.5V dropout voltage is limited by input voltage range limitations. TYPICAL CHARACTERISTICS Table of Graphs FIGURE vs Output current 2, 3, 4 vs Free-air temperature 5, 6, 7 Ground current vs Free-air temperature 8, 9 Power supply ripple rejection vs Frequency 10 Output spectral noise density vs Frequency 11 Output impedance vs Frequency 12 Dropout voltage vs Free-air temperature Output voltage Line transient response 13 14, 16 Load transient response 15, 17 Output voltage vs Time 18 Dropout voltage vs Input voltage 19 vs Output current, TA = 25°C 21 vs Output current, TJ = 125°C 22 vs Output Current, TA = 25°C 23 vs Output current, TJ = 125°C 24 Equivalent series resistance (ESR) POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS OUTPUT VOLTAGE vs OUTPUT CURRENT OUTPUT VOLTAGE vs OUTPUT CURRENT 1.7965 3.2835 VO = 1.8 V VI = 2.8V TA = 25°C VO = 3.3 V VI = 4.3 V TA = 25°C 1.7960 VO – Output Voltage – V 3.2830 VO – Output Voltage – V 3.2825 3.2820 3.2815 3.2810 1.7955 1.7950 1.7945 3.2805 1.7940 3.2800 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 IO – Output Current – A 0.9 1 0 0.1 0.2 0.3 Figure 2 0.6 0.7 0.8 0.9 1 OUTPUT VOLTAGE vs FREE-AIR TEMPERATURE 2.4960 3.32 VO = 2.5 V VI = 3.5 V TA = 25°C 2.4955 3.31 VO – Output Voltage – V 2.4950 VO – Output Voltage – V 0.5 Figure 3 OUTPUT VOLTAGE vs OUTPUT CURRENT 2.4945 2.4940 2.4935 2.4930 VO = 3.3 V VI = 4.3 V 3.30 3.29 IO = 1 A IO = 1 mA 3.28 3.27 3.26 2.4925 2.4920 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 3.25 –60 –40 –20 0 20 40 Figure 4 Figure 5 POST OFFICE BOX 655303 60 80 100 120 140 TA – Free-Air Temperature – °C IO – Output Current – A 8 0.4 IO – Output Current – A • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS OUTPUT VOLTAGE vs FREE-AIR TEMPERATURE OUTPUT VOLTAGE vs FREE-AIR TEMPERATURE 2.515 1.815 VO = 1.8 V VI = 2.8 V 2.510 1.805 IO = 1 A 1.800 IO = 1 mA 1.795 1.790 VO – Output Voltage – V VO – Output Voltage – V 1.810 VO = 2.5 V VI = 3.5 V 2.505 2.500 IO = 1 A 2.495 IO = 1 mA 2.490 2.485 1.785 –60 –40 –20 0 20 40 60 80 100 120 140 2.480 –60 –40 TA – Free-Air Temperature – °C –20 0 Figure 6 60 80 100 120 GROUND CURRENT vs FREE-AIR TEMPERATURE 96 92 VO = 3.3 V VI = 4.3 V 94 VO = 1.8 V VI = 2.8 V 92 88 IO = 1 mA 90 86 84 82 IO = 1 mA 80 IO = 1 A 78 IO = 500 mA 76 Ground Current – µ A Ground Current – µ A 40 Figure 7 GROUND CURRENT vs FREE-AIR TEMPERATURE 90 20 TA – Free-Air Temperature – °C 88 86 IO = 500 mA 84 82 80 78 74 76 72 –60 –40 –20 0 20 40 60 80 100 120 140 IO = 1 A 74 –60 –40 –20 TA – Free-Air Temperature – °C 0 20 40 60 80 100 120 140 TA – Free-Air Temperature – °C Figure 8 Figure 9 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 9 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS OUTPUT SPECTRAL NOISE DENSITY vs FREQUENCY POWER SUPPLY RIPPLE REJECTION vs FREQUENCY 10–5 Vn – Output Spectral Noise Density – V/ Hz PSRR – Power Supply Ripple Rejection – dB 90 VO = 3.3 V VI = 4.3 V CO = 10 µF IO = 1 A TA = 25°C 80 70 60 50 40 30 20 10 0 – 10 10 100 1k 10k 100k VI = 4.3 V CO = 10 µF TA = 25°C IO = 7 mA 10–6 IO = 1 A 10–7 10–8 102 1M 103 f – Frequency – Hz Figure 11 DROPOUT VOLTAGE vs FREE-AIR TEMPERATURE OUTPUT IMPEDANCE vs FREQUENCY 103 0 IO = 1 A VDO – Dropout Voltage – mV Zo – Output Impedance – Ω VI = 4.3 V CO = 10 µF TA = 25°C IO = 1 mA 10–1 IO = 1 A 102 101 IO = 10 mA 100 10–1 VO = 3.3 V CO = 10 µF 102 103 104 f – Frequency – kHz 105 106 10–2 –60 –40 –20 IO = 0 0 20 40 Figure 13 POST OFFICE BOX 655303 60 80 100 120 140 TA – Free-Air Temperature – °C Figure 12 10 105 f – Frequency – Hz Figure 10 10–2 101 104 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS LINE TRANSIENT RESPONSE LOAD TRANSIENT RESPONSE ∆ VO – Change in Output Voltage – mV 3.8 2.8 VO = 1.8 V IL = 10 mA CL = 10 µF TA = 25°C 20 0 –20 0 20 40 VO = 1.8 V VI = 2.8 V CL = 100 µF TA = 25°C 50 0 –50 –100 I O – Output Current – A ∆ VO – Change in Output Voltage – mV VI – Input Voltage – V 100 60 1 0.5 0 0 80 100 120 140 160 180 200 t – Time – µs 20 40 60 Figure 15 Figure 14 LOAD TRANSIENT RESPONSE 100 ∆ VO – Change in Output Voltage – mV VI – Input Voltage – V LINE TRANSIENT RESPONSE VO = 3.3 V CL = 10 µF TA = 25°C 5.3 I O – Output Current – A 4.3 ∆ VO – Change in Output Voltage – mV 80 100 120 140 160 180 200 t – Time – µs 10 0 –10 0 20 40 60 80 100 120 140 160 180 200 t – Time – µs VO = 3.3 V CL =100 µF TA = 25°C 50 0 –50 –100 1 0.5 0 0 20 40 60 80 100 120 140 160 180 200 t – Time – µs Figure 17 Figure 16 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 11 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS DROPOUT VOLTAGE vs INPUT VOLTAGE 4 900 3 800 IO = 1A VDO – Dropout Voltage – mV VO– Output Voltage – V OUTPUT VOLTAGE vs TIME (AT STARTUP) 2 1 Enable Pulse – V 0 0 700 600 500 TA = 25°C 400 TA = 125°C 300 200 TA = –40°C 100 0 0 20 40 60 80 100 120 140 160 180 200 t – Time – µs 2.5 Figure 18 VI 3 3.5 4 VI – Input Voltage – V 4.5 5 Figure 19 To Load IN OUT + EN CO GND RL ESR Figure 20. Test Circuit for Typical Regions of Stability (Figures 21 through 24) (fixed output options) 12 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 TYPICAL CHARACTERISTICS TYPICAL REGION OF STABILITY TYPICAL REGION OF STABILITY EQUIVALENT SERIES RESISTANCE† vs OUTPUT CURRENT EQUIVALENT SERIES RESISTANCE† vs OUTPUT CURRENT 10 ESR – Equivalent Series Resistance – Ω ESR – Equivalent series restance – Ω 10 Region of Instability 1 Region of Stability Vo = 3.3V CL = 4.7µF VI = 4.3V TA = 25°C 0.1 0 200 400 600 800 Region of Instability 1 Region of Stability VO = 3.3 V Cl = 4.7 µF VI = 4.3 V TJ = 125°C 0.1 1000 0 200 IO – Output Current – mA 400 Figure 21 800 1000 Figure 22 TYPICAL REGION OF STABILITY TYPICAL REGION OF STABILITY EQUIVALENT SERIES RESISTANCE† vs OUTPUT CURRENT EQUIVALENT SERIES RESISTANCE† vs OUTPUT CURRENT 10 10 ESR – Equivalent Series Resistance – Ω ESR – Equivalent series restance – Ω 600 IO – Output Current – mA Region of Instability 1 Region of Stability VO = 3.3V CL = 22µF VI = 4.3V TA = 25°C 0.1 0 200 400 600 800 1000 Region of Instability 1 Region of Stability VO = 3.3V Cl = 22µF VI = 4.3V TJ = 125°C 0.1 0 IO – Output Current – mA 200 400 600 800 1000 IO – Output Current – mA Figure 23 Figure 24 † Equivalent series resistance (ESR) refers to the total series resistance, including the ESR of the capacitor, any series resistance added externally, and PWB trace resistance to CO. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 13 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 APPLICATION INFORMATION The features of the TPS767D3xx family (low-dropout voltage, ultra low quiescent current, power-saving shutdown mode, and a supply-voltage supervisor) and the power-dissipation properties of the TSSOP PowerPAD package have enabled the integration of the dual LDO regulator with high output current for use in DSP and other multiple voltage applications. Figure 25 shows a typical dual-voltage DSP application. R1 100 kΩ R2 100 kΩ U1 TPS767D325 2 3 4 5 5V 6 C0 1 µF 7 8 9 10 11 12 13 14 PG NC 1RESET NC NC 1GND 1EN NC 1FB/NC 1IN 1OUT 1IN 1OUT NC 2RESET NC NC 2GND 2EN NC NC 2IN 2OUT 2IN 2OUT NC NC NC NC 28 27 RESET to DSP 26 VC549 DSP 25 24 23 2.5 V 22 D1 21 20 C3 33 µF 19 18 17 + DL4148 1 CVDD (Core Supply) D3 DL5817 16 D2 15 3.3 V C1 1 µF DVDD (I/O Supply) C2 33 µF GND GND Figure 25. Dual-Voltage DSP Application DSP power requirements include very high transient currents that must be considered in the initial design. This design uses higher-valued output capacitors to handle the large transient currents. device operation The TPS767D3xx features very low quiescent current, which remain virtually constant even with varying loads. Conventional LDO regulators use a pnp pass element, the base current of which is directly proportional to the load current through the regulator (IB = IC/β). Close examination of the data sheets reveals that these devices are typically specified under near no-load conditions; actual operating currents are much higher as evidenced by typical quiescent current versus load current curves. The TPS767D3xx uses a PMOS transistor to pass current; because the gate of the PMOS is voltage driven, operating current is low and invariable over the full load range. The TPS767D3xx specifications reflect actual performance under load condition. 14 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 Another pitfall associated with the pnp-pass element is its tendency to saturate when the device goes into dropout. The resulting drop in β forces an increase in IB to maintain the load. During power up, this translates to large start-up currents. Systems with limited supply current may fail to start up. In battery-powered systems, it means rapid battery discharge when the voltage decays below the minimum required for regulation. The TPS767D3xx quiescent current remains low even when the regulator drops out, eliminating both problems. The TPS767D3xx family also features a shutdown mode that places the output in the high-impedance state (essentially equal to the feedback-divider resistance) and reduces quiescent current to under 2 µA. If the shutdown feature is not used, EN should be tied to ground. Response to an enable transition is quick; regulated output voltage is typically reestablished in 120 µs. minimum load requirements The TPS767D3xx family is stable even at zero load; no minimum load is required for operation. FB - pin connection (adjustable version only) The FB pin is an input pin to sense the output voltage and close the loop for the adjustable option. The output voltage is sensed through a resistor divider network as is shown in Figure 27 to close the loop. Normally, this connection should be as short as possible; however, the connection can be made near a critical circuit to improve performance at that point. Internally, FB connects to a high-impedance wide-bandwidth amplifier and noise pickup feeds through to the regulator output. Routing the FB connection to minimize/avoid noise pickup is essential. In fixed output options this pin is a no connect. external capacitor requirements An input capacitor is not required; however, a ceramic bypass capacitor (0.047 pF to 0.1 µF) improves load transient response and noise rejection when the TPS767D3xx is located more than a few inches from the power supply. A higher-capacitance electrolytic capacitor may be necessary if large (hundreds of milliamps) load transients with fast rise times are anticipated. Like all low dropout regulators, the TPS767D3xx requires an output capacitor connected between OUT and GND to stabilize the internal control loop. The minimum recommended capacitance value is 10 µF and the ESR (equivalent series resistance) must be between 50 mΩ and 1.5 Ω. Capacitor values 10 µF or larger are acceptable, provided the ESR is less than 1.5 Ω. Solid tantalum electrolytic, aluminum electrolytic, and multilayer ceramic capacitors are all suitable, provided they meet the requirements described previously. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 15 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 external capacitor requirements (continued) When necessary to achieve low height requirements along with high output current and/or high ceramic load capacitance, several higher ESR capacitors can be used in parallel to meet the previous guidelines. TPS767D3xx 5 VI 6 IN 28 RESET 250 kΩ IN 24 OUT C1 0.1 µF 50 V 4 RESET EN VO 23 OUT + GND CO 10 µF 3 Figure 26. Typical Application Circuit (Fixed Versions) for Single Channel programming the TPS767D301 adjustable LDO regulator The output voltage of the TPS767D301 adjustable regulator is programmed using an external resistor divider as shown in Figure 27. The output voltage is calculated using: V O ǒ) Ǔ + Vref R1 R2 1 (1) Where: Vref = 1.1834 V typ (the internal reference voltage) Resistors R1 and R2 should be chosen for approximately 50-µA divider current. Lower value resistors can be used but offer no inherent advantage and waste more power. Higher values should be avoided as leakage currents at FB increase the output voltage error. The recommended design procedure is to choose R2 = 30.1 kΩ to set the divider current at 50 µA and then calculate R1 using: R1 + ǒ Ǔ V V O ref *1 (2) R2 OUTPUT VOLTAGE PROGRAMMING GUIDE TPS767D301 VI 0.1 µF IN RESET RESET Output 250 kΩ >2.7 V EN OUT <0.5V R1 FB / NC GND + OUTPUT VOLTAGE R1 33.2 30.1 kΩ 3.3 V 53.6 30.1 kΩ VO 3.6 V 61.9 30.1 kΩ CO 4 75V 90.8 30.1 kΩ 10 µF R2 POST OFFICE BOX 655303 UNIT 2.5 V Figure 27. TPS767D301 Adjustable LDO Regulator Programming 16 R2 • DALLAS, TEXAS 75265 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 Reset indicator The TPS767D3xx features a RESET output that can be used to monitor the status of the regulator. The internal comparator monitors the output voltage: when the output drops to 95% (typical) of its regulated value, the RESET output transistor turns on, taking the signal low. The open-drain output requires a pullup resistor. If not used, it can be left floating. RESET can be used to drive power-on reset circuitry or as a low-battery indicator. regulator protection The TPS767D3xx PMOS-pass transistor has a built-in back-gate diode that safely conducts reverse currents when the input voltage drops below the output voltage (e.g., during power down). Current is conducted from the output to the input and is not internally limited. When extended reverse voltage is anticipated, external limiting may be appropriate. The TPS767D3xx also features internal current limiting and thermal protection. During normal operation, the TPS767D3xx limits output current to approximately 1.7 A. When current limiting engages, the output voltage scales back linearly until the overcurrent condition ends. While current limiting is designed to prevent gross device failure, care should be taken not to exceed the power dissipation ratings of the package. If the temperature of the device exceeds 150°C(typ), thermal-protection circuitry shuts it down. Once the device has cooled below 130°C(typ), regulator operation resumes. power dissipation and junction temperature Specified regulator operation is assured to a junction temperature of 125°C; the maximum junction temperature should be restricted to 125°C under normal operating conditions. This restriction limits the power dissipation the regulator can handle in any given application. To ensure the junction temperature is within acceptable limits, calculate the maximum allowable dissipation, PD(max), and the actual dissipation, PD, which must be less than or equal to PD(max). The maximum-power-dissipation limit is determined using the following equation: P T max * T J A + D(max) R qJA Where: TJmax is the maximum allowable junction temperature RθJA is the thermal resistance junction-to-ambient for the package, i.e., 27.9°C/W for the 28-terminal PWP with no airflow. TA is the ambient temperature. ǒ Ǔ The regulator dissipation is calculated using: P D + VI * VO I O Power dissipation resulting from quiescent current is negligible. Excessive power dissipation will trigger the thermal protection circuit. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 17 TPS767D301, TPS767D318, TPS767D325 DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS SLVS209B – JULY 1999 – REVISED APRIL 2000 MECHANICAL DATA PWP (R-PDSO-G**) PowerPAD PLASTIC SMALL-OUTLINE PACKAGE 20-PIN SHOWN 0,30 0,19 0,65 20 0,10 M 11 Thermal Pad (See Note D) 4,50 4,30 0,15 NOM 6,60 6,20 Gage Plane 1 10 0,25 A 0°– 8° 0,75 0,50 Seating Plane 0,15 0,05 1,20 MAX PINS ** 0,10 14 16 20 24 28 A MAX 5,10 5,10 6,60 7,90 9,80 A MIN 4,90 4,90 6,40 7,70 9,60 DIM 4073225/E 03/97 NOTES: A. B. C. D. All linear dimensions are in millimeters. This drawing is subject to change without notice. Body dimensions do not include mold flash or protrusions. The package thermal performance may be enhanced by bonding the thermal pad to an external thermal plane. This pad is electrically and thermally connected to the backside of the die and possibly selected leads. E. Falls within JEDEC MO-153 PowerPAD is a trademark of Texas Instruments Incorporated. 18 POST OFFICE BOX 655303 • 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. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent TI deems necessary to support this warranty. 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