TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 POWER GOOD FAST-TRANSIENT RESPONSE 7.5-A LOW-DROPOUT VOLTAGE REGULATORS FEATURES * * * * * * * * * TO-220 (KC) PACKAGE (TOP VIEW) 7.5-A Low-Dropout Voltage Regulator Available in 1.5-V, 1.8-V, 2.5-V, and 3.3-V Fixed-Output and Adjustable Versions Open Drain Power-Good (PG) Status Output (Fixed Options Only) Dropout Voltage Typically 400 mV at 7.5 A (TPS75933) Low 125 A Typical Quiescent Current Fast Transient Response 3% Tolerance Over Specified Conditions for Fixed-Output Versions Available in 5-Pin TO-220 and TO-263 Surface-Mount Packages Thermal Shutdown Protection EN IN GND OUTPUT FB/PG 1 2 3 4 5 TO-263 (KTT) PACKAGE (TOP VIEW) EN IN GND OUTPUT FB/PG 1 2 3 4 5 DESCRIPTION The TPS759xx family of 7.5-A low dropout (LDO) regulators contains four fixed voltage option regulators with integrated power-good (PG) and an adjustable voltage option regulator. These devices are capable of supplying 7.5 A of output current with a dropout of 400 mV (TPS75933). Therefore, the devices are capable of performing a 3.3-V to 2.5-V conversion. Quiescent current is 125 A at full load and drops below 10 A when the devices are disabled. The TPS759xx is designed to have fast transient response for large load current changes. TPS75933 IO = 7.5 A VDO - Dropout Voltage - mV 500 400 300 200 200 VO = 1.5 V Co = 100 F 100 di 1 A s dt 0 -100 -200 10 5 100 0 0 -40 -25 -10 -5 20 35 50 65 80 95 110 125 TJ - Junction Temperature - C 0 20 40 60 I O - Output Current - A 600 TPS75915 LOAD TRANSIENT RESPONSE VO - Change in Output Voltage - mV DROPOUT VOLTAGE vs JUNCTION TEMPERATURE 80 100 120 140 160 180 200 t - Time - s 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. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright (c) 2000-2004, Texas Instruments Incorporated TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 Because the PMOS device behaves as a low-value resistor, the dropout voltage is very low (typically 400 mV at an output current of 7.5 A for the TPS75933) 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 125 A over the full range of output current, 1 mA to 7.5 A). These two key specifications yield a significant improvement in operating life for battery-powered systems. The device is enabled when EN is connected to a low-level voltage. 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 less than 1 A at TJ = 25C. The power-good terminal (PG) is an active low, open drain output, which can be used to implement a power-on reset or a low-battery indicator. The TPS759xx is offered in 1.5-V, 1.8-V, 2.5-V, and 3.3-V fixed-voltage versions and in an adjustable version (programmable over the range of 1.22 V to 5 V). Output voltage tolerance is specified as a maximum of 3% over line, load, and temperature ranges. The TPS759xx family is available in a 5-pin TO-220 (KC) and TO-263 (KTT) packages. AVAILABLE OPTIONS TJ OUTPUT VOLTAGE (TYP) TO-220 (KC) TO-263 (KTT) (1) 3.3 V TPS75933KC TPS75933KTT 2.5 V TPS75925KC TPS75925KTT 1.8 V TPS75918KC TPS75918KTT 1.5 V TPS75915KC TPS75915KTT Adjustable 1.22 V to 5 V TPS75901KC TPS75901KTT -40C to 125C (1) The TPS75901 is programmable using an external resistor divider (see application information). Add T for KTT devices in 50-piece reel. Add R for KTT devices in 500-piece reel. 2 VI IN PG OUT 1 F 5 PG 4 VO 1 EN + GND Co(1) 47 F 3 (1) See application information section for capacitor selection details. Figure 1. Typical Application Configuration (For Fixed Output Options) Terminal Functions (TPS759xx) TERMINAL NAME NO. I/O DESCRIPTION EN 1 I FB/PG 5 I/O GND 3 IN 2 I Input voltage OUTPUT 4 O Regulated output voltage 2 Enable input Feedback input voltage for adjustable device/PG output for fixed options Regulator ground TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 FUNCTIONAL BLOCK DIAGRAM - ADJUSTABLE VERSION VOUT VIN Current Sense UVLO SHUTDOWN ILIM _ GND R1 + FB EN UVLO R2 Thermal Shutdown External to the Device Bandgap Reference VIN Vref = 1.22 V FUNCTIONAL BLOCK DIAGRAM - FIXED VERSION VOUT VIN UVLO Current Sense SHUTDOWN ILIM _ R1 + GND UVLO EN R2 Thermal Shutdown Vref = 1.22 V VIN Bandgap Reference PG Falling Edge Delay 3 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TPS759xx PG TIMING DIAGRAM VIN1 VUVLO VUVLO t VOUT VIT+(see Note A) Threshold Voltage VIT- (see Note A) t PG Output t NOTE A: VIT -Trip voltage is typically 9% lower than the output voltage (91%VO) VIT- to VIT+ is the hysteresis voltage. DETAILED DESCRIPTION The TPS759xx family includes four fixed-output voltage regulators (1.5 V, 1.8 V, 2.5 V, and 3.3 V), and an adjustable regulator, the TPS75901 (adjustable from 1.22 V to 5 V). The bandgap voltage is typically 1.22 V. PIN FUNCTIONS Enable (EN) The EN terminal is an input which enables or shuts down the device. If EN is a logic high, the device will be in shutdown mode. When EN goes to logic low, then the device will be enabled. Power-Good (PG) The PG terminal for the fixed voltage option devices is an open drain, active low output that indicates the status of VO (output of the LDO). When VOreaches approximately 91% of the regulated voltage, PG will go to a low impedance state. It will go to a high-impedance state when VO falls below 91% (i.e., over load condition) of the regulated voltage. The open drain output of the PG terminal requires a pullup resistor. Feedback (FB) FB is an input terminal used for the adjustable-output option and must be connected to the output terminal either directly, in order to generate the minimum output voltage of 1.22 V, or through an external feedback resistor divider for other output voltages. The FB connection should be as short as possible. It is essential to route it in such a way to minimize/avoid noise pickup. Adding RC networks between FB terminal and VO to filter noise is not recommended because it may cause the regulator to oscillate. 4 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 Input Voltage (IN) The VIN terminal is an input to the regulator. Output Voltage (OUTPUT) The VOUTPUT terminal is an output to the regulator. ABSOLUTE MAXIMUM RATINGS over operating junction temperature range (unless otherwise noted) (1) TPS759XX Input voltage range (2) VI -0.3 V to 6 V Voltage range at EN -0.3 V to 6 V Maximum PG voltage (TPS759xx) 6V Peak output current Internally limited Continuous total power dissipation See Dissipation Rating Table Output voltage VO (OUTPUT, FB) Operating junction temperature range TJ -40C to 150C Storage temperature range Tstg -65C to 150C ESD rating HBM 2 kV CDM 500 V (1) (2) 5.5 V 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. DISSIPATION RATING TABLE (1) (2) (3) PACKAGE RJC (C/W) RJA (C/W) (1) TO-220 2 58.7 (2) TO-263 2 38.7 (3) For both packages, the RJAvalues were computed using JEDEC high K board (2S2P) with 1 ounce internal copper plane and ground plane. There was no air flow across the packages. RJA was computed assuming a vertical, free standing TO-220 package with pins soldered to the board. There is no heatsink attached to the package. RJA was computed assuming a horizontally mounted TO-263 package with pins soldered to the board. There is no copper pad underneath the package. RECOMMENDED OPERATING CONDITIONS VI (1) Input voltage VO Output voltage range IO Output current TJ Operating virtual junction temperature (1) MIN MAX 2.8 5.5 V 1.22 5 V 0 7.5 A -40 125 C To calculate the minimum input voltage for your maximum output current, use the following equation: VI(min)= VO(max)+ VDO(max UNIT load). 5 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 ELECTRICAL CHARACTERISTICS over recommended operating junction temperature range (TJ = -40C to 125C), VI = VO(typ) + 1 V, IO = 1 mA, EN = 0 V, CO = 100 F (unless otherwise noted) PARAMETER TEST CONDITIONS MIN 1.22 V VO 5.5 V, TJ = 25C Adjustable voltage 1.5 V Output Output voltage (1) 1.8 V Output 2.5 V Output 3.3 V Output Quiescent current (GND current) (3), (4) Output voltage line regulation (VO/VO) (4) 1.03 VO 1.22 V VO 5.5 V, TJ = 0 to 125C (2) 0.98 VO 1.02 VO TJ = 25C, 2.8 V < VI < 5.5 V 2.8 V VI 5.5 V 1.746 2.425 3.3 TPS75915 200 VO + 1 V VI 5.5 V, TJ = 25C 0.04 VO + 1 V VI < 5.5 V 0.1 BW = 300 Hz to 50 kHz, TJ = 25C, VI = 2.8 V VO = 0 V 8 TPS75901 FB = 1.5 V TPS75915 f = 100 Hz, TJ = 25C, VI = 2.8 V, IO = 7.5 A IO(PG) = 300 A, V(PG) 0.8 V PG trip threshold voltage Fixed options only VO decreasing PGhysteresis voltage Fixed options only Measured at VO PGoutput low voltage Fixed options only VI = 2.8 V, IO(PG) = 1 mA PG leakage current Fixed options only V(PG) = 5 V Low level EN input voltage 6 IO = 0 mA to 7.5 A The adjustable option operates with a 2% tolerance over TJ = 0 to 125C. IO = 0 mA to 7.5 A If VO 1.8 V then VImin = 2.8 V, VImax = 5.5 V: VOVImax 2.8V Line regulator (mV) (%V) 1000 100 If VO 2.5 V then VImin = VO + 1 V, VImax = 5.5 V: VOVImax VO 1V Line regulator (mV) (%V) 1000 100 14 A C 10 A 1 A 58 dB 0 V 93 0.15 -1 High level EN input voltage Vrms 0.5 EN = 0 V %/V A 89 -1 A 0.1 -1 EN = VI V 150 EN = VI Minimum input voltage for valid PG (1) (2) (3) (4) 10 V %/V 35 EN = VI , TJ = 25C Standby current Input current (EN) 3.399 125 Thermal shutdown junction temperature Power supply ripple rejection 2.575 3.201 TJ = 25C V 1.854 2.5 TJ = 25C, 4.3 V < VI < 5.5 V 4.3 V VI 5.5 V 1.545 1.8 TJ = 25C, 3.5 V < VI < 5.5 V 3.5 V VI 5.5 V V 1.5 1.455 TJ = 25C, 2.8 V < VI < 5.5 V 2.8 V VI 5.5 V UNIT VO 0.97 VO 0.35 Output current limit FB input current MAX 1.22 V VO 5.5 V Load regulation (3) Output noise voltage TYP 0 %VO %VO 0.4 V 1 A 1 A 1 A 2 V 0.7 V TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 ELECTRICAL CHARACTERISTICS (continued) over recommended operating junction temperature range (TJ = -40C to 125C), VI = VO(typ) + 1 V, IO = 1 mA, EN = 0 V, CO = 100 F (unless otherwise noted) PARAMETER VO VI (5) Dropout voltage (3.3 V output) (5) TEST CONDITIONS MIN IO = 7.5 A, VI = 3.2 V, TJ = 25C TYP MAX 400 IO = 7.5 A, VI = 3.2 V mV 750 Discharge transistor current VO = 1.5 V, TJ = 25C 10 UVLO TJ = 25C, VI rising 2.2 UVLO hysteresis TJ = 25C, VI falling 25 mV mA 2.75 100 UNIT V mV IN voltage equals VO(Typ) - 100 mV; TPS75915, TPS75918, and TPS75925 dropout voltage limited by input voltage range limitations (i.e., TPS75933 input voltage is set to 3.2 V for the purpose of this test). 7 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS Table of Graphs FIGURE vs Output current 2, 3 vs Junction temperature 4, 5 Ground current vs Junction temperature 6 Power supply ripple rejection vs Frequency 7 Output spectral noise density vs Frequency 8 zo Output impedance vs Frequency 9 VDO Dropout voltage vs Input voltage 10 vs Junction temperature 11 VI Minimum required input voltage vs Output voltage 12 VO Output voltage Line transient response 13, 15 Load transient response VO 14, 16 Output voltage and enable voltage vs Time (start-up) 17 Equivalent series resistance (ESR) vs Output current 19, 20 TPS75933 OUTPUT VOLTAGE vs OUTPUT CURRENT TPS75915 OUTPUT VOLTAGE vs OUTPUT CURRENT 1.545 3.345 VI = 2.8 V TJ = 25C VI = 4.3 V TJ = 25C 1.530 VO - Output Voltage - V VO - Output Voltage - V 3.330 3.315 3.3 3.285 1.5 1.485 1.470 3.270 3.255 0 1.5 3 4.5 IO - Output Current - A Figure 2. 8 1.515 6 7.5 1.455 0 1.5 3 4.5 IO - Output Current - A Figure 3. 6 7.5 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) TPS75933 OUTPUT VOLTAGE vs JUNCTION TEMPERATURE TPS75915 OUTPUT VOLTAGE vs JUNCTION TEMPERATURE 3.345 1.545 VI = 4.3 V VI = 2.8 V 1.530 VO - Output Voltage - V VO - Output Voltage - V 3.33 3.315 3.3 3.285 1.515 1.5 1.485 1.470 3.270 3.255 -40 -25 10 5 20 35 50 65 80 1.455 -40 -25 -10 95 110 125 TJ - Junction Temperature - C 35 50 65 80 95 110 125 Figure 5. TPS759xx GROUND CURRENT vs JUNCTION TEMPERATURE TPS75933 POWER SUPPLY RIPPLE REJECTION vs FREQUENCY 90 PSRR - Power Supply Ripple Rejection - dB VI = 5 V IO = 7.5 A 114 Ground Current - A 20 Figure 4. 118 116 5 TJ - Junction Temperature - C 112 110 108 106 104 102 -40 -25 -10 5 20 35 50 65 80 95 110 125 VI = 4.3 V Co = 100 F TJ = 25C 80 70 IO = 1 mA 60 50 40 30 IO = 7.5 A 20 10 0 10 100 1k 10k 100k TJ - Junction Temperature - C f - Frequency - Hz Figure 6. Figure 7. 1M 10M 9 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) TPS75933 OUTPUT SPECTRAL NOISE DENSITY vs FREQUENCY 2.5 100 VI = 4.3 V VO = 3.3 V Co = 100 F TJ = 25C 2 10 IO = 7.5 A 1.5 IO = 1 mA 1 1 0.1 0.01 0.0001 100 1k f - Frequency - Hz 10k 100k 0.00001 10 100 1k 10k 100k f - Frequency - Hz Figure 8. Figure 9. TPS75901 DROPOUT VOLTAGE vs INPUT VOLTAGE TPS75933 DROPOUT VOLTAGE vs JUNCTION TEMPERATURE 1M 10M 600 700 IO = 7.5 A IO = 7.5 A 600 500 VDO - Dropout Voltage - mV VDO - Dropout Voltage - mV IO = 7.5 A 0.001 0.5 0 10 TJ = 125C 500 400 TJ = 25C 300 TJ = -40C 200 400 300 200 100 100 0 2.5 3 3.5 4 VI - Input Voltage - V Figure 10. 10 VI = 4.3 V Co = 100 F TJ = 25C IO = 1 mA z o - Output Impedance - Hz Output Spectral Noise Density - V/ TPS75933 OUTPUT IMPEDANCE vs FREQUENCY 4.5 5 0 -40 -25 -10 -5 20 35 50 65 80 95 110 125 TJ - Junction Temperature - C Figure 11. TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) MINIMUM REQUIRED INPUT VOLTAGE vs OUTPUT VOLTAGE TPS75915 LINE TRANSIENT RESPONSE VO - Change in Output Voltage - mV 4 TJ = 125C TJ = 25C TJ = -40C 50 0 -50 3.7 2.8 3 2.25 2.5 2.75 VO - Output Voltage - V 100 150 200 250 300 350 400 450 500 t - Time - s Figure 13. TPS75915 LOAD TRANSIENT RESPONSE TPS75933 LINE TRANSIENT RESPONSE di 1 A s dt 0 -100 VO = 3.3 V IO = 7.5 A Co = 100 F 50 0 -50 -100 10 5 0 20 40 60 80 100 120 140 160 180 200 t - Time - s Figure 14. I O - Output Current - A -200 0 50 Figure 12. VO = 1.5 V Co = 100 F 100 0 3.5 3.25 5.3 4.3 0 50 VI - Input Voltage - V 200 2 1.75 VI - Input Voltage - V 2.8 2 1.5 VO - Change in Output Voltage - mV VO = 1.5 V IO = 7.5 A Co = 100 F -100 3 VO - Change in Output Voltage - mV VI- Minimum Required Input Voltage - V IO = 7.5 A 100 150 200 250 300 350 400 450 500 t - Time - s Figure 15. 11 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) TPS75933 OUTPUT VOLTAGE AND ENABLE VOLTAGE vs TIME (START-UP) VO - Output Voltage - V VO = 3.3 V Co = 100 F 100 0 di 1 A s dt -100 -200 10 7.5 5 0 0 20 40 60 80 100 120 140 160 180 200 t - Time - s Figure 16. 12 Enable Voltage - V 200 I O - Output Current - A VO - Change in Output Voltage - mV TPS75933 LOAD TRANSIENT RESPONSE VI = 4.3 V IO = 10 mA TJ = 25C 3.3 0 4.3 0 0 0.2 0.4 0.6 t - Time (Start-Up) - ms Figure 17. 0.8 1 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 TYPICAL CHARACTERISTICS (continued) To Load IN VI OUT + EN RL Co GND ESR Figure 18. Test Circuit for Typical Regions of Stability (See Figure 19 and Figure 20) (Fixed Output Options) TYPICAL REGION OF STABILITY EQUIVALENT SERIES RESISTANCE(A) vs OUTPUT CURRENT 10 Co = 680 F TJ = 25C ESR - Equivalent Series Resistance - ESR - Equivalent Series Resistance - 10 TYPICAL REGION OF STABILITY EQUIVALENT SERIES RESISTANCE(A) vs OUTPUT CURRENT 1 Region of Stability 0.1 Co = 47 F TJ = 25C 1 Region of Stability 0.2 Region of Instability 0.015 Region of Instability 0.01 0.01 0 1.5 3 4.5 6 7.5 0 1.5 3 4.5 IO - Output Current - A IO - Output Current - A Figure 19. Figure 20. 6 7.5 A. Equivalent series resistance (ESR) refers to the total series resistance, including the ESR of the capacitor, ay series resistance added externally, and PWB trace resistance to CO. 13 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION The amount of heat that an LDO linear regulator generates is directly proportional to the amount of power it dissipates during operation. All integrated circuits have a maximum allowable junction temperature (TJmax) above which normal operation is not assured. A system designer must design the operating environment so that the operating junction temperature (TJ) does not exceed the maximum junction temperature (TJmax). The two main environmental variables that a designer can use to improve thermal performance are air flow and external heatsinks. The purpose of this information is to aid the designer in determining the proper operating environment for a linear regulator that is operating at a specific power level. In general, the maximum expected power (PD(max)) consumed by a linear regulator is computed as: P max V V I V xI D I(avg) O(avg) O(avg) I(avg) (Q) (1) Where: * * * * VI(avg) is the average input voltage. VO(avg) is the average output voltage. IO(avg) is the average output current. I(Q) is the quiescent current. For most TI LDO regulators, the quiescent current is insignificant compared to the average output current; therefore, the term VI(avg) x I(Q) can be neglected. The operating junction temperature is computed by adding the ambient temperature (TA) and the increase in temperature due to the regulator's power dissipation. The temperature rise is computed by multiplying the maximum expected power dissipation by the sum of the thermal resistances between the junction and the case (RJC), the case to heatsink (RCS), and the heatsink to ambient (RSA). Thermal resistances are measures of how effectively an object dissipates heat. Typically, the larger the device, the more surface area available for power dissipation and the lower the object's thermal resistance. Figure 21 illustrates these thermal resistances for (a) a TO-220 package attached to a heatsink, and (b) a TO-263 package mounted on a JEDEC High-K board. C B A TJ RJC A B A B TC RCS C RSA TA TO-220 Package (a) Figure 21. Thermal Resistances 14 TO-263 Package (b) C TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION (continued) Equation 2 summarizes the computation: T J T PDmax x R R R A JC CS SA (2) The RJC is specific to each regulator as determined by its package, lead frame, and die size provided in the regulator's data sheet. The RSA is a function of the type and size of heatsink. For example, black body radiator type heatsinks, like the one attached to the TO-220 package in Figure 21(a), can have RCS values ranging from 5C/W for very large heatsinks to 50C/W for very small heatsinks. The RCSis a function of how the package is attached to the heatsink. For example, if a thermal compound is used to attach a heatsink to a TO-220 package, RCSof 1C/W is reasonable. Even if no external black body radiator type heatsink is attached to the package, the board on which the regulator is mounted will provide some heatsinking through the pin solder connections. Some packages, like the TO-263 and TI's TSSOP PowerPADTM packages, use a copper plane underneath the package or the circuit board's ground plane for additional heatsinking to improve their thermal performance. Computer aided thermal modeling can be used to compute very accurate approximations of an integrated circuit's thermal performance in different operating environments (e.g., different types of circuit boards, different types and sizes of heatsinks, different air flows, etc.). Using these models, the three thermal resistances can be combined into one thermal resistance between junction and ambient (RJA). This RJA is valid only for the specific operating environment used in the computer model. Equation 2 simplifies into Equation 3: T T PDmax x R J A JA Rearranging Equation 3 gives Equation 4: T -T R J A JA P max D (3) (4) Using Equation 3 and the computer model generated curves shown in Figure 22 and Figure 25, a designer can quickly compute the required heatsink thermal resistance/board area for a given ambient temperature, power dissipation, and operating environment. TO-220 POWER DISSIPATION The TO-220 package provides an effective means of managing power dissipation in through-hole applications. The TO-220 package dimensions are provided in the Mechanical Data section at the end of the data sheet. A heatsink can be used with the TO-220 package to effectively lower the junction-to-ambient thermal resistance. To illustrate, the TPS75925 in a TO-220 package was chosen. For this example, the average input voltage is 3.3 V, the output voltage is 2.5 V, the average output current is 3 A, the ambient temperature 55C, the air flow is 150 LFM, and the operating environment is the same as documented below. Neglecting the quiescent current, the maximum average power is: P Dmax (3.3 - 2.5) V x 3 A 2.4 W (5) Substituting TJmax for TJ into Equation 4 gives Equation 6: R max (125 - 55) C2.4 W 29 CW JA (6) From Figure 22, RJA vs Heatsink Thermal Resistance, a heatsink with RSA = 22C/W is required to dissipate 2.4 W. The model operating environment used in the computer model to construct Figure 22 consisted of a standard JEDEC High-K board (2S2P) with a 1 oz. internal copper plane and ground plane. Since the package pins were soldered to the board, 450 mm2 of the board was modeled as a heatsink. Figure 23 shows the side view of the operating environment used in the computer model. 15 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION (continued) 65 R JA - Thermal Resistance - C/W Natural Convection 55 Air Flow = 150 LFM 45 Air Flow = 250 LFM Air Flow = 500 LFM 35 25 15 No Heatsink 5 25 20 15 10 5 RSA - Heatsink Thermal Resistance - C/W 0 Figure 22. Thermal Resistance vs Heatsink Thermal Resistance 0.21 mm 0.21 mm 1 oz. Copper Power Plane 1 oz. Copper Ground Plane Figure 23. From the data in Figure 22 and rearranging Equation 4, the maximum power dissipation for a different heatsink RSA and a specific ambient temperature can be computed (see Figure 24). 16 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION (continued) 10 PD - Power Dissipation Limit - W TA = 55C Air Flow = 500 LFM Air Flow = 250 LFM Air Flow = 150 LFM Natural Convection No Heatsink 1 20 10 RSA - Heatsink Thermal Resistance - C/W 0 Figure 24. Power Dissipation vs Heatsink Thermal Resistance The TO-263 package provides an effective means of managing power dissipation in surface mount applications. The TO-263 package dimensions are provided in the Mechanical Data section at the end of the data sheet. The addition of a copper plane directly underneath the TO-263 package enhances the thermal performance of the package. To illustrate, the TPS75925 in a TO-263 package was chosen. For this example, the average input voltage is 3.3V, the output voltage is 2.5 V, the average output current is 3 A, the ambient temperature 55C, the air flow is 150 LFM, and the operating environment is the same as documented below. Neglecting the quiescent current, the maximum average power is: P Dmax (3.3 - 2.5) V x 3 A 2.4 W (7) Substituting TJmax for TJ into Equation 4 gives Equation 8: R max (125 - 55) C2.4 W 29 CW JA (8) 2 From Figure 25, RJA vs Copper Heatsink Area, the ground plane needs to be 2 cm for the part to dissipate 2.4W. The model operating environment used in the computer model to construct Figure 25 consisted of a standard JEDEC High-K board (2S2P) with a 1 oz. internal copper plane and ground plane. The package is soldered to a 2 oz. copper pad. The pad is tied through thermal vias to the 1 oz. ground plane. Figure 26 shows the side view of the operating environment used in the computer model. 17 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION (continued) 40 R JA - Thermal Resistance - C/W No Air Flow 35 150 LFM 30 250 LFM 25 20 15 0 0.01 0.1 1 10 Copper Heatsink Area - cm2 100 Figure 25. Thermal Resistance vs Copper Heatsink Area 2 oz. Copper Solder Pad with 25 Thermal Vias 1 oz. Copper Power Plane 1 oz. Copper Ground Plane Thermal Vias, 0.3 mm Diameter, 1.5 mm Pitch Figure 26. From the data in Figure 25 and rearranging Equation 4, the maximum power dissipation for a different ground plane area and a specific ambient temperature can be computed (see Figure 27). 18 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 THERMAL INFORMATION (continued) 5 PD - Maximum Power Dissipation - W TA = 55C 250 LFM 4 150 LFM 3 No Air Flow 2 1 0 0.01 0.1 1 10 Copper Heatsink Area - cm2 100 Figure 27. Maximum Power Dissipation vs Copper Heatsink Area 19 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 APPLICATION INFORMATION PROGRAMMING THE TPS75901 ADJUSTABLE LDO REGULATOR The output voltage of the TPS75901 adjustable regulator is programmed using an external resistor divider as shown in Figure 28. The output voltage is calculated using: V O V ref 1 R1 R2 Where: Vref = 1.224 V typ (the internal reference voltage) (9) Resistors R1 and R2 should be chosen for approximately 40-A 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 k to set the divider current at 40 A and then calculate R1 using: R1 V V O 1 ref R2 (10) TPS75901 VI 1 F OUTPUT VOLTAGE PROGRAMMING GUIDE IN OUTPUT VOLTAGE 2V 0.7 V EN OUT VO R1 FB GND Co R1 R2 UNIT 2.5 V 31.6 30.1 k 3.3 V 51 30.1 k 3.6 V 58.3 30.1 k R2 Figure 28. TPS75901 Adjustable LDO Regulator Programming REGULATOR PROTECTION The TPS759xx PMOS-pass transistor has a built-in back diode that 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 TPS759xx also features internal current limiting and thermal protection. During normal operation, the TPS759xx limits output current to approximately 10 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 150C (typ), thermal-protection circuitry shuts it down. Once the device has cooled below 130C (typ), regulator operation resumes. INPUT CAPACITOR For a typical application, a ceramic input bypass capacitor (0.22 F-1 F) is recommended to ensure device stability. This capacitor should be as close as possible to the input pin. Due to the impedance of the input supply, large transient currents will cause the input voltage to droop. If this droop causes the input voltage to drop below the UVLO threshold, the device will turn off. Therefore, it is recommended that a larger capacitor be placed in parallel with the ceramic bypass capacitor at the regulator's input. The size of this capacitor depends on the output current, response time of the main power supply, and the main power supply's distance to the regulator. At a minimum, the capacitor should be sized to ensure that the input voltage does not drop below the minimum UVLO threshold voltage during normal operating conditions. 20 TPS75901, TPS75915 TPS75918, TPS75925, TPS75933 www.ti.com SLVS318E - DECEMBER 2000 - REVISED MARCH 2004 APPLICATION INFORMATION (continued) OUTPUT CAPACITOR As with most LDO regulators, the TPS759xx requires an output capacitor connected between OUT and GND to stabilize the internal control loop. The minimum recommended capacitance value is 47 F with an ESR (equivalent series resistance) of at least 200 m. As shown in Figure 29, most capacitor and ESR combinations with a product of 47e-6 x 0.2 = 9.4e-6 or larger will be stable, provided the capacitor value is at least 47 F. Solid tantalum electrolytic and aluminum electrolytic capacitors are all suitable, provided they meet the requirements described in this section. Larger capacitors provide a wider range of stability and better load transient response. This information along with the ESR graphs, Figure 19, Figure 20, and Figure 29, is included to assist in selection of suitable capacitance for the user's application. When necessary to achieve low height requirements along with high output current and/or high load capacitance, several higher ESR capacitors can be used in parallel to meet these guidelines. 1000 Output Capacitance - F Region of Stability ESR min x Co = Constant 100 47 Region xofCInstability Y = ESRmin o 10 0.01 0.1 ESR - Equivalent Series Resistance - 0.2 Figure 29. Output Capacitance vs Equivalent Series Resistance 21 PACKAGE OPTION ADDENDUM www.ti.com 17-Aug-2012 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/ Ball Finish MSL Peak Temp (3) (Requires Login) TPS75901KC ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75901KCG3 ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75901KTT OBSOLETE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75901KTTR ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75901KTTRG3 ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75901KTTT ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75901KTTTG3 ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75915KC ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75915KCG3 ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75915KTT OBSOLETE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75915KTTR ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75915KTTRG3 ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75915KTTT ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75915KTTTG3 ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75918KC ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75918KCG3 ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75918KTT OBSOLETE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com Orderable Device 17-Aug-2012 Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/ Ball Finish MSL Peak Temp (3) TPS75918KTTT ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75918KTTTG3 ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75925KC ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75925KCG3 ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75925KTT OBSOLETE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75925KTTR ACTIVE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75925KTTRG3 ACTIVE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75925KTTT ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75925KTTTG3 ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75933KC ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75933KCG3 ACTIVE TO-220 KC 5 50 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type TPS75933KTT OBSOLETE DDPAK/ TO-263 KTT 5 TBD Call TI Call TI TPS75933KTTR ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75933KTTRG3 ACTIVE DDPAK/ TO-263 KTT 5 500 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75933KTTT ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR TPS75933KTTTG3 ACTIVE DDPAK/ TO-263 KTT 5 50 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. Addendum-Page 2 Samples (Requires Login) PACKAGE OPTION ADDENDUM www.ti.com 17-Aug-2012 PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 3 PACKAGE MATERIALS INFORMATION www.ti.com 17-Aug-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant TPS75901KTTR DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75901KTTT DDPAK/ TO-263 KTT 5 50 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75915KTTR DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75915KTTT DDPAK/ TO-263 KTT 5 50 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75918KTTT DDPAK/ TO-263 KTT 5 50 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75925KTTT DDPAK/ TO-263 KTT 5 50 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75933KTTR DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 TPS75933KTTT DDPAK/ TO-263 KTT 5 50 330.0 24.4 10.6 15.6 4.9 16.0 24.0 Q2 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 17-Aug-2012 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) TPS75901KTTR DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 TPS75901KTTT DDPAK/TO-263 KTT 5 50 367.0 367.0 45.0 TPS75915KTTR DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 TPS75915KTTT DDPAK/TO-263 KTT 5 50 367.0 367.0 45.0 TPS75918KTTT DDPAK/TO-263 KTT 5 50 367.0 367.0 45.0 TPS75925KTTT DDPAK/TO-263 KTT 5 50 367.0 367.0 45.0 TPS75933KTTR DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 TPS75933KTTT DDPAK/TO-263 KTT 5 50 367.0 367.0 45.0 Pack Materials-Page 2 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All semiconductor products (also referred to herein as "components") are sold subject to TI's terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI's terms and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. TI assumes no liability for applications assistance or the design of Buyers' products. Buyers are responsible for their products and applications using TI components. To minimize the risks associated with Buyers' products and applications, Buyers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions. Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety-critical applications. In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI's goal is to help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and requirements. Nonetheless, such components are subject to these terms. No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties have executed a special agreement specifically governing such use. Only those TI components which TI has specifically designated as military grade or "enhanced plastic" are designed and intended for use in military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use. TI has specifically designated certain components which meet ISO/TS16949 requirements, mainly for automotive use. Components which have not been so designated are neither designed nor intended for automotive use; and TI will not be responsible for any failure of such components to meet such requirements. Products Applications Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers DLP(R) Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps DSP dsp.ti.com Energy and Lighting www.ti.com/energy Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial Interface interface.ti.com Medical www.ti.com/medical Logic logic.ti.com Security www.ti.com/security Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video RFID www.ti-rfid.com OMAP Applications Processors www.ti.com/omap TI E2E Community e2e.ti.com Wireless Connectivity www.ti.com/wirelessconnectivity Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright (c) 2012, Texas Instruments Incorporated