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TPS543321

ACTIVE

3.8V to 18V Input, 3A, 200kHz to 2.2MHz synchronous buck converter

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Data sheet

TPS543321

ACTIVE
Data sheet Order now

Product details

Rating Catalog Topology Buck Iout (max) (A) 3 Vin (max) (V) 18 Vin (min) (V) 3.8 Vout (max) (V) 17.64 Vout (min) (V) 0.6 Features Adjustable soft start, Adjustable switching frequency, Enable, External Sync, Light Load Efficiency, Low Quiescent Current, Phase Interleaving, UVLO adjustable Control mode current mode Operating temperature range (°C) -40 to 150 Iq (typ) (A) 0.000028 Duty cycle (max) (%) 98
Rating Catalog Topology Buck Iout (max) (A) 3 Vin (max) (V) 18 Vin (min) (V) 3.8 Vout (max) (V) 17.64 Vout (min) (V) 0.6 Features Adjustable soft start, Adjustable switching frequency, Enable, External Sync, Light Load Efficiency, Low Quiescent Current, Phase Interleaving, UVLO adjustable Control mode current mode Operating temperature range (°C) -40 to 150 Iq (typ) (A) 0.000028 Duty cycle (max) (%) 98
VQFN-HR (RQF) 9 3 mm² 2 x 1.5
  • Configured for a wide range of applications
    • 3.8V to 18V input voltage range
    • Up to 5A (TPS543521), 4A (TPS543421), 3A (TPS543321) continuous output current
    • 0.6V ±1% reference voltage (–40°C to 150°C)
    • 70ns and 114ns minimum switching on and off-time
    • 8us maximum switching on-time
    • 98% maximum duty cycle
  • High efficiency
    • Integrated 47mΩ and 21mΩ MOSFETs
    • Low quiescent current of 28uA (typical)
  • Ease of use and small design size
    • Peak current control mode with internal compensation
    • 200kHz to 2.2MHz selectable frequency
    • Synchronizable to an external clock (support phase shift): 200kHz to 2.2MHz
    • Selectable PFM / FCCM at light load condition
    • Selectable adjustable soft-start time, power-good indicator function
    • Good EMI performance with frequency spread spectrum and optimized pinout
    • Hiccup overcurrent (OC) limit for both high-side and low-side MOSFETs
    • Non-latched protections for over temperature protection (OTP), overcurrent protection (OCP), overvoltage protection (OVP), undervoltage protection (UVP), and undervoltage lockout (UVLO)
    • Integrated bootstrap capacitor to support single-layer PCB layout
    • –40°C to 150°C operating junction temperature
    • 1.5mm × 2.0mm QFN package
  • Create a custom design with the TPS543x21 using the WEBENCH Power Designer
  • Configured for a wide range of applications
    • 3.8V to 18V input voltage range
    • Up to 5A (TPS543521), 4A (TPS543421), 3A (TPS543321) continuous output current
    • 0.6V ±1% reference voltage (–40°C to 150°C)
    • 70ns and 114ns minimum switching on and off-time
    • 8us maximum switching on-time
    • 98% maximum duty cycle
  • High efficiency
    • Integrated 47mΩ and 21mΩ MOSFETs
    • Low quiescent current of 28uA (typical)
  • Ease of use and small design size
    • Peak current control mode with internal compensation
    • 200kHz to 2.2MHz selectable frequency
    • Synchronizable to an external clock (support phase shift): 200kHz to 2.2MHz
    • Selectable PFM / FCCM at light load condition
    • Selectable adjustable soft-start time, power-good indicator function
    • Good EMI performance with frequency spread spectrum and optimized pinout
    • Hiccup overcurrent (OC) limit for both high-side and low-side MOSFETs
    • Non-latched protections for over temperature protection (OTP), overcurrent protection (OCP), overvoltage protection (OVP), undervoltage protection (UVP), and undervoltage lockout (UVLO)
    • Integrated bootstrap capacitor to support single-layer PCB layout
    • –40°C to 150°C operating junction temperature
    • 1.5mm × 2.0mm QFN package
  • Create a custom design with the TPS543x21 using the WEBENCH Power Designer

The TPS543x21 is a high-efficiency, high-voltage input, and easy-to-use, synchronous buck converter with high design flexibility. With the wide operating input voltage range of 3.8V to 18V, the TPS543x21 is designed for systems powered from 5V, 12V power-bus rails. The device supports up to 5A, 4A, 3A continuous output current and 98% maximum duty cycle.

TPS543x21 uses fixed frequency peak current control with internal compensation for fast transient response and good line and load regulation. With the optimized internal loop compensation, the device eliminates the need for external compensation over a wide output voltage range and switching frequency. Integrated bootstrap capacitor helps achieve single layer PCB and reduce external component count.

TPS543x21 allows high design flexibility with wide supported switching frequency of 200kHz – 2.2MHz set by the RT/SYNC pin. The device has the option for pulse frequency modulation (PFM), forced continuous conduction modulation (FCCM) at light load condition and adjustable soft-start (SS) time / power-good (PG) indicator with different configuration of the MODE pin.

TPS543x21 provides protection functions including thermal shutdown, input undervoltage lockout, cycle-by-cycle current limit, and hiccup short-circuit protection. TPS543x21 is available in 9-pin, 1.5mm × 2.0mm QFN package, and the pinout is available for single-layer PCB layout and the junction temperature is specified from –40°C to 150°C.

The TPS543x21 is a high-efficiency, high-voltage input, and easy-to-use, synchronous buck converter with high design flexibility. With the wide operating input voltage range of 3.8V to 18V, the TPS543x21 is designed for systems powered from 5V, 12V power-bus rails. The device supports up to 5A, 4A, 3A continuous output current and 98% maximum duty cycle.

TPS543x21 uses fixed frequency peak current control with internal compensation for fast transient response and good line and load regulation. With the optimized internal loop compensation, the device eliminates the need for external compensation over a wide output voltage range and switching frequency. Integrated bootstrap capacitor helps achieve single layer PCB and reduce external component count.

TPS543x21 allows high design flexibility with wide supported switching frequency of 200kHz – 2.2MHz set by the RT/SYNC pin. The device has the option for pulse frequency modulation (PFM), forced continuous conduction modulation (FCCM) at light load condition and adjustable soft-start (SS) time / power-good (PG) indicator with different configuration of the MODE pin.

TPS543x21 provides protection functions including thermal shutdown, input undervoltage lockout, cycle-by-cycle current limit, and hiccup short-circuit protection. TPS543x21 is available in 9-pin, 1.5mm × 2.0mm QFN package, and the pinout is available for single-layer PCB layout and the junction temperature is specified from –40°C to 150°C.
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Technical documentation

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* Data sheet TPS543x21 3.8V to 18V, 5A, 4A, 3A, Synchronous Buck Converters With User Selectable Mode datasheet PDF | HTML 18 Mar 2025

Design & development

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Evaluation board

TPS543521EVM — TPS543521 evaluation module

The TPS543521EVM is a fully assembled and tested circuit for evaluating the TPS543521 converter. The evaluation module is configured to operate from input voltage range of 3.8V to 18V and produce a regulated 5.0V output with up to 5A load current. Most settings of the device can be easily adjusted (...)
User guide: PDF | HTML
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VQFN-HR (RQF) 9 Ultra Librarian
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