Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsPMICsPMIC - DC/DC voltage regulator Holder MSOP 10

EFFICIENCY

LOAD CURRENT

0 0.1 0.2 0.3 0.4

Load Current – A

Efficiency – %

100

0.5

V = 12 V

V = 5 V

f = 700 kHz

OUT

VIN

GND

BOOT

VSENSE

COMP

TPS5401

RT/CLK

SS/TR

PWRGD

BOOT

OUT

TPS5401

www.ti.com

SLVSAB0 –DECEMBER 2010

0.5-A, 42-V Input, Step-Down SWIFT™ Converter

Check for Samples: TPS5401

FEATURES

• 0.8-V ±3.5% Internal Voltage Reference

• 3.5-V to 42-V Input Voltage Range

• MSOP10 With PowerPAD™ Package

• 200-mΩ High-Side MOSFET • Supported by SwitcherPro™ Software Tool

(http://focus.ti.com/docs/toolsw/folders/print/s

• High Efficiency at Light Loads With a

witcherpro.html)

Pulse-Skipping Eco-mode™ Control Scheme

• For SWIFT™ Power Products Documentation,

• 116-mA Operating Quiescent Current

See the TI Web Site at http://www.ti.com/swift

• 1.3-mA Shutdown Current

• 100-kHz to 2.5-MHz Switching Frequency

APPLICATIONS

• Synchronizes to External Clock

• 12-V and 24-V Industrial and Commercial

• Adjustable Slow Start/Sequencing

Low-Power Systems

• E-Meters

• UV and OV Power-Good Output

• Adjustable UVLO Voltage and Hysteresis

DESCRIPTION

The TPS5401 device is a 42-V, 0.5-A, step-down regulator with an integrated high-side MOSFET. Current-mode

control provides simple external compensation and flexible component selection. A low-ripple pulse-skip mode

reduces the supply current to 116 mA when outputting regulated voltage with no load. Using the enable pin,

shutdown supply current is reduced to 1.3 mA when the enable pin is low.

Undervoltage lockout is internally set at 2.5 V, but can be increased using the enable pin. The output voltage

start-up ramp is controlled by the slow-start pin that can also be configured for sequencing/tracking. An

open-drain power-good signal indicates the output is within 94% to 107% of its nominal voltage.

A wide switching-frequency range allows efficiency and external component size optimization. Frequency

foldback and thermal shutdown protect the part during an overload condition.

The TPS5401 is available in a 10-pin thermally enhanced MSOP PowerPAD package.

SPACER

SIMPLIFIED SCHEMATIC

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.

2Eco-mode, PowerPAD, SwitcherPro, SWIFT are trademarks 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.

Summary of content (41 pages)

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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 0.5-A, 42-V Input, Step-Down SWIFT™ Converter Check for Samples: TPS5401 FEATURES • • • 1 • • • 2 • • • • • • • 3.5-V to 42-V Input Voltage Range 200-mΩ High-Side MOSFET High Efficiency at Light Loads With a Pulse-Skipping Eco-mode™ Control Scheme 116-mA Operating Quiescent Current 1.3-mA Shutdown Current 100-kHz to 2.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 THERMAL INFORMATION (continued) TPS5401 THERMAL METRIC (1) MSOP (10 PINS) UNIT qJB Junction-to-board thermal resistance 44.6 °C/W yJT Junction-to-top characterization parameter 1.4 °C/W yJB Junction-to-board characterization parameter 22.8 °C/W qJC(bottom) Junction-to-case(bottom) thermal resistance 25.6 °C/W ELECTRICAL CHARACTERISTICS TJ = –40°C to 150°C, VIN = 3.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com ELECTRICAL CHARACTERISTICS (continued) TJ = –40°C to 150°C, VIN = 3.5 V to 42 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 2500 kHz 720 kHz 2200 kHz TIMING RESISTOR AND EXTERNAL CLOCK (RT/CLK PIN) Switching-frequency range using RT mode fSW Switching frequency 100 RT = 200 kΩ 450 Switching-frequency range using CLK mode 581 300 Minimum CLK input pulse width 40 RT/CLK high threshold 1.9 RT/CLK low threshold 0.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DEVICE INFORMATION PIN CONFIGURATION MSOP10 (TOP VIEW) BOOT 1 VIN 2 10 Thermal Pad (11) PH 9 GND 8 COMP EN 3 SS/TR 4 7 VSENSE RT/CLK 5 6 PWRGD PIN FUNCTIONS PIN I/O DESCRIPTION NAME NO. BOOT 1 O A bootstrap capacitor is required between BOOT and PH. If the voltage on this capacitor is below the minimum required by the output device, the output is forced to switch off until the capacitor is refreshed.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 TYPICAL CHARACTERISTICS VOLTAGE REFERENCE vs JUNCTION TEMPERATURE 0.816 500 VIN = 12 V VIN = 12 V 375 Vref – Voltage Reference – V rDS(on) – Static Drain-Source On-State Resistance – mW ON-RESISTANCE vs JUNCTION TEMPERATURE VBOOT – VPH = 3 V 250 VBOOT – VPH = 6 V 125 0 –50 –25 0 25 50 75 100 TJ – Junction Temperature – °C 125 0.808 0.800 0.792 0.784 –50 150 0 25 50 75 100 TJ – Junction Temperature – °C 125 150 Figure 1. Figure 2.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com TYPICAL CHARACTERISTICS (continued) EA TRANSCONDUCTANCE DURING SLOW-START vs JUNCTION TEMPERATURE EA TRANSCONDUCTANCE vs JUNCTION TEMPERATURE 40 150 VIN = 12 V gm – EA Transconductance – mA/V gm – EA Transconductance – mA/V VIN = 12 V 30 20 10 –50 –25 0 25 50 75 100 TJ – Junction Temperature – °C 125 130 110 90 70 50 –50 150 –25 0 25 50 Figure 7. 150 –3.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 TYPICAL CHARACTERISTICS (continued) SS/TR DISCHARGE CURRENT vs JUNCTION TEMPERATURE SWITCHING FREQUENCY vs VSENSE 120 100 VIN = 12 V TJ = 25°C 80 115 % of Nominal fsw ISS/TR – SS/TR Pin Discharge Current – mA VIN = 12 V 110 60 40 105 20 100 –50 0 –25 0 25 50 75 100 TJ – Junction Temperature – °C 125 150 0 Figure 14.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 OVERVIEW The TPS5401 device is a 42-V, 0.5-A, step-down (buck) regulator with an integrated high-side n-channel MOSFET. To improve performance during line and load transients, the device implements a constant-frequency, current-mode control which reduces output capacitance and simplifies external frequency compensation design.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION Fixed Frequency PWM Control The TPS5401 uses an adjustable fixed-frequency, peak current mode control. The output voltage is compared through external resistors on the VSENSE pin to an internal voltage reference by an error amplifier which drives the COMP pin. An internal oscillator initiates the turnon of the high-side power switch. The error amplifier output is compared to the high-side power-switch current.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DETAILED DESCRIPTION (continued) VOUTac VPH IL Figure 25. Pulse-Skip Mode Operation Low-Dropout Operation and Bootstrap Voltage (BOOT) The TPS5401 has an integrated boot regulator, and requires a small ceramic capacitor between the BOOT and PH pins to provide the gate-drive voltage for the high-side MOSFET. The BOOT capacitor is refreshed when the high-side MOSFET is off and the low-side diode conducts. The value of this ceramic capacitor should be 0.1 mF.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION (continued) voltage and output voltage is greater than 2.1 V, at which point the BOOT UVLO threshold is exceeded, and the device starts switching again until the desired output voltage is reached. This operating condition persists until the input voltage and/or the load current increases.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DETAILED DESCRIPTION (continued) Enabling and Adjusting Undervoltage Lockout The TPS5401 is disabled when the VIN pin voltage falls below 2.5 V. If an application requires a higher undervoltage lockout (UVLO), use the EN pin as shown in Figure 28 to adjust the input voltage UVLO by using the two external resistors. Though it is not necessary to use the UVLO adjust resistors, for operation it is highly recommended to provide consistent power-up behavior.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION (continued) VEN VSS/TR VVSENSE VOUT Figure 29. Operation of SS/TR Pin When Starting Overload Recovery Circuit The TPS5401 has an overload recovery (OLR) circuit. The OLR circuit slow-starts the output from the overload voltage to the nominal regulation voltage once the fault condition is removed.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DETAILED DESCRIPTION (continued) TPS5401 EN PWRGD EN VEN1 SS /TR SS /TR VPWRGD1 PWRGD VOUT1 VOUT2 Figure 30. Schematic for Sequential Start-Up Sequence Figure 31. Sequential Start-Up Using EN and PWRGD TPS54160 TPS5401 3 EN 4 SS/TR 6 PWRGD VEN1, VEN2 VOUT1 TPS5401 TPS54160 3 EN 4 SS/TR 6 PWRGD VOUT2 Figure 32. Schematic for Ratiometric Start-Up Sequence Figure 33.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION (continued) TPS5401 EN VOUT1 SS /TR PWRGD TPS5401 VOUT2 EN R1 SS / TR R2 PWRGD VSENSE R3 R4 Figure 34. Schematic for Ratiometric and Simultaneous Start-Up Sequence Ratiometric and simultaneous power supply sequencing can be implemented by connecting the resistor network of R1 and R2 shown in Figure 34 to the output of the power supply that must be tracked or to another voltage reference source.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DETAILED DESCRIPTION (continued) DV = VOUT1 - VOUT2 (7) R1 > 2800 ´ VOUT1 - 180 ´ DV (8) VEN VEN VOUT1 VOUT1 VOUT2 Figure 35. Ratiometric Start-Up With Vout2 Leading Vout1 VOUT2 Figure 36. Ratiometric Start-Up With Vout1 Leading Vout2 VEN VOUT1 VOUT2 Figure 37.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION (continued) Constant Switching Frequency and Timing Resistor (RT/CLK Pin) The switching frequency of the TPS5401 is adjustable over a wide range from approximately 100 kHz to 2500 kHz by placing a resistor on the RT/CLK pin. The RT/CLK pin voltage is typically 0.5 V and must have a resistor to ground to set the switching frequency.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 DETAILED DESCRIPTION (continued) IL Inductor current Rdc Inductor resistance VIN Maximum input voltage VOUT Output voltage VOUTSC Output voltage during short Vd Diode voltage drop rDS(on) Switch on resistance tON Controllable on-time ƒDIV Frequency divide equals (1, 2, 4, or 8) fSW – Switching Frequency – kHz 2500 Skip 2000 1500 Shift 1000 500 VOUT = 5 V 0 10 20 30 VIN – Input Voltage – V 40 Figure 38. Maximum Switching Frequency vs.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com DETAILED DESCRIPTION (continued) Power Good (PWRGD Pin) The PWRGD pin is an open-drain output. Once the VSENSE pin is between 94% and 107% of the internal voltage reference, the PWRGD pin is de-asserted and the pin floats. It is recommended to use a pullup resistor between the values of 10 kΩ and 100 kΩ to a voltage source that is 5.5 V or less. PWRGD is in a defined state once the VIN input voltage is greater than 1.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 APPLICATION INFORMATION Typical Application The TPS5401 is good for the E-meter application. The power supply design is a challenge work to E-meter designers because it must get enough output current from a wide input voltage range with a limited input power. For example, in China, a single-phase or three-phase E-meter must work properly with an input AC electricity voltage range from 0.7 Un to 1.9 Un. Here Un is the phase voltage of 220 V.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com Switching Frequency The first step is to decide on a switching frequency for the regulator. Typically, the user may want to choose the highest switching frequency possible, because this produces the smallest solution size. The high switching frequency allows for lower-valued inductors and smaller output capacitors compared to a power supply that switches at a lower frequency. Alternatively, the user may choose a lower switching frequency to improve efficiency.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 Using the design example values, IOUT(max) = 0.5 A, CIN = 4.4 mF,and fSW = 700 kHz, yields an input voltage ripple of 40.6 mV and a maximum rms input ripple current of 0.25 A when VIN is equal to 10 V, which is 2 times the output voltage of 5 V. IINRMS = IOUT × VINRIPPLE = (VIN -VOUT ) VOUT × VIN VIN (13) IOUT(max) × 0.25 CIN × fSW (14) Table 4. Capacitor Types VENDOR VALUE (mF) 1 to 2.2 Murata 1 to 4.7 1 1 to 2.2 1 10 1.8 Vishay 1 to 1.2 1 to 3.
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TPS5401 SLVSAB0 – DECEMBER 2010 ILRIPPLE = IL(RMS) = www.ti.com ( VIN(max) - VOUT ) ´ VOUT VIN(max) ´ LOUT ´ fSW (IOUT )2 + IL(peak) = IOUT (17) 1 æ ( VIN(max) - VOUT ) ´ VOUT ´ç 12 çè VIN(max) ´ LOUT ´ fSW ö ÷ ÷ ø 2 I + RIPPLE 2 (18) (19) As the equation set demonstrates, lower ripple currents reduce the output voltage ripple of the regulator but require a larger value of inductance.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 inductor, IOH is the output current under heavy load, IOL is the output under light load, VFIN is the final peak output voltage, and VINI is the initial capacitor voltage. For this example, the worst-case load step is from 0.5 A to 0 A. The output voltage increases during this load transition, and the stated maximum in our specification is 4% of the output voltage. This makes VFIN = 1.04 × 5 V = 5.2 V.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com The B160A has a junction capacitance (CJ) of 110 pF. Using Equation 24, the selected diode dissipates 0.29 W. This power dissipation, depending on mounting techniques, should produce a 5.9°C temperature rise in the diode when the input voltage is 42 V and the load current is 0.5 A.
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TPS5401 www.ti.com fZmod = SLVSAB0 – DECEMBER 2010 1 2p ´ RESR ´ COUT (27) A type 2A compensation scheme is recommended for the TPS5401. As RC, CC, CP shown in Figure 41, the compensation components are chosen to set the desired loop crossover frequency and phase margin for output filter components. The type 2A compensation has the following characteristics: a dc gain, a low-frequency pole, and a mid-frequency zero / pole pair. VOUT VSENSE Type2A gmEA V ref COMP RO CO RC CP CC Figure 41.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com And, the mid-frequency pole is given by Equation 32. 1 fP1 = 2p ´ RC ´ CP (32) The first step is to choose the closed-loop crossover frequency fCO. In general, the closed-loop crossover frequency could be less than 1/10 of the minimum operating frequency. But for the TPS5401, it is recommended that the maximum closed-loop crossover frequency be not greater than 40 kHz. For this example, we choose 15-kHz crossover frequency.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 PH = 20 V div PH = 20 V div VOUT = 20 mV / div (ac coupled) VOUT = 20 mV / div (ac coupled) Inductor Current = 100 mA div Inductor Current = 100 mA div Time = 1 usec / div Time = 1 usec / div Figure 44. Output Ripple, CCM Figure 45.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com 60 100 180 90 Phase 40 80 20 Gain - dB VIN = 15 V 60 50 VIN = 24 V 40 30 60 0 Phase - ° 70 Efficiency - % 120 VIN = 7.5 V 0 Gain −20 −60 −40 −120 VIN = 35 V 20 10 0 0.001 0.01 0.1 1 −60 100 1000 IOUT - Output Current - A Figure 50. Light-Load Efficiency 0.10 0.08 0.08 VIN = 24 V 0.06 IOUT = 0.25 A 0.06 0.04 Regulation - % 0.04 Regulation - % −180 1000000 100000 Figure 51. Overall Loop-Frequency Response 0.10 0.02 0.00 −0.
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TPS5401 www.ti.com SLVSAB0 – DECEMBER 2010 Power Dissipation Estimate The following formulas show how to estimate the IC power dissipation under continuous-conduction mode (CCM) operation. These equations should not be used if the device is working in discontinuous-conduction mode (DCM). The power dissipation of the IC includes conduction loss (Pcon), switching loss (Psw), gate-drive loss (PGD), and supply current (PSUP). V Pcon = IOUT 2 ´ r DS(on) ´ OUT VIN (36) Psw = VIN2 ´ lOUT ´ 0.
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TPS5401 SLVSAB0 – DECEMBER 2010 www.ti.com Layout Layout is a critical portion of good power-supply design. There are several signals paths that conduct fast-changing currents or voltages that can interact with stray inductance or parasitic capacitance to generate noise or degrade the power-supply performance. To help eliminate these problems, the VIN pin should be bypassed to ground with a low-ESR ceramic bypass capacitor with X5R or X7R dielectric.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE MATERIALS INFORMATION www.ti.com 9-Sep-2011 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 TPS5401DGQR MSOPPower PAD DGQ 10 2500 330.0 12.4 5.3 3.3 1.3 8.0 12.0 Q1 TPS5401DGQT MSOPPower PAD DGQ 10 250 180.0 12.4 5.3 3.3 1.3 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 9-Sep-2011 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) TPS5401DGQR MSOP-PowerPAD DGQ 10 2500 346.0 346.0 35.0 TPS5401DGQT MSOP-PowerPAD DGQ 10 250 203.0 203.0 35.
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