onsemi NCP1597BMNTWG

Overview

NCP1597BMNTWG from onsemi is a fixed-frequency, synchronous buck regulator IC integrating high-side P-channel and low-side N-channel MOSFETs, delivering up to 2 A output current with 0.8 V to 3.3 V adjustable output voltage, 1 MHz switching frequency, and internal current-mode control - used in DSP power supplies and USB-powered peripherals.

For engineers reviewing the NCP1597BMNTWG datasheet, pinout, applications, or equivalent options, key selection considerations include input voltage range (4.0–5.5 V), thermal shutdown threshold (185 °C), soft-start ramp time (1.0 ms), and DFN10 package thermal pad requirements for PCB layout and thermal management.

Technical Context

The NCP1597BMNTWG implements internally compensated current-mode PWM control with a transconductance error amplifier and fixed 1 MHz oscillator, enabling stable regulation across 4.0–5.5 V input and down to 0.8 V output. It features adaptive dead-time gate driving to minimize shoot-through and body-diode conduction loss in the integrated MOSFETs.

Protection architecture includes cycle-by-cycle current limiting (2.7–4.3 A regulation limit), hiccup-mode overcurrent response, undervoltage lockout (3.2–3.8 V threshold with 335 mV hysteresis), and thermal shutdown at 185 °C with 30 °C hysteresis - all implemented without external components.

Key Specifications

Pinout & Package

Package: DFN10 (3 mm × 3 mm, 0.5 mm pitch), thermally enhanced with exposed pad (EP) soldered to PCB ground plane for optimal thermal performance (R_JA = 68.5 °C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck regulator applications.

Compared with MP2315GJ-Z and TPS562210DRCT, the NCP1597BMNTWG offers tighter input voltage optimization (4–5.5 V), superior light-load efficiency via adaptive dead-time, and robust hiccup-mode protection - making it ideal for USB- and 5 V–based embedded systems where size, thermal headroom, and reliability are prioritized over wide-VIN flexibility.

Availability

NCP1597BMNTWG is available at Aetrix Electronics and suitable for DSP power supplies, USB peripheral designs, and set-top box SoC core rails requiring stable component supply, long-term lifecycle assurance, and Pb-free compliance.

Supply support for NCP1597BMNTWG includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The NCP1597BMNTWG belongs to onsemi's high-efficiency DC-DC converter product line, designed specifically for space-constrained, thermally sensitive 5 V input applications such as portable computing peripherals and digital entertainment systems.

FAQ

What is the minimum output voltage supported by the NCP1597BMNTWG?

The NCP1597BMNTWG supports an output voltage as low as 0.8 V, set by its internal 0.800 V feedback reference voltage and external resistor divider. This allows direct regulation for modern low-voltage DSP, FPGA, and microcontroller cores without additional external references or level-shifting circuitry. The reference tolerance is ±12 mV over −40 °C to +85 °C ambient, ensuring stable low-voltage operation across temperature.

Does the NCP1597BMNTWG support startup into a pre-biased output?

Yes, the NCP1597BMNTWG explicitly supports pre-biased startup: during soft-start, the low-side MOSFET remains off until the internal reference ramp reaches the FB pin voltage, preventing reverse current flow into a partially charged output capacitor. This feature is confirmed in the DETAILED DESCRIPTION section and enables safe integration into systems with shared power rails or standby supplies.

What is the maximum recommended output capacitance for reliable startup of the NCP1597BMNTWG?

The NCP1597BMNTWG limits maximum output capacitance to ensure successful soft-start under worst-case conditions. With 1 ms soft-start time and minimum soft-start current limit of 4.0 A, the maximum allowed output capacitance is calculated as ~546 µF for a 3.3 V/2.0 A output with 20% ripple. Exceeding this value risks failure to regulate due to insufficient charge current during ramp-up.

How does the NCP1597BMNTWG handle overcurrent faults?

The NCP1597BMNTWG uses cycle-by-cycle current limiting with hiccup-mode recovery: if overcurrent persists for seven consecutive switching cycles, it shuts down both MOSFETs, discharges the compensation network, waits 2 ms, then attempts a new soft-start. This limits average power dissipation during shorts and enables automatic recovery upon fault removal - a behavior verified in the PROTECTIONS section of the datasheet.

Is the exposed thermal pad of the NCP1597BMNTWG electrically connected to ground?

Yes, the exposed pad (EP) of the NCP1597BMNTWG is electrically connected to PGND and must be soldered to a large PCB ground plane. It serves dual roles: providing low-inductance power ground return for the LX and PGND pins, and enhancing thermal conduction from the die to the board. Failure to solder the pad results in degraded thermal performance (R_JA increases significantly) and potential thermal shutdown under load.