MP174GJ-P

MP174GJ-P is a voltage regulator for offline switchers and AC/DC converters. It features a wide range of inputs, a low start-up current, internal soft-start, overvoltage protection (OVP) and short-circuit protection (SCP), and conversion to either forward or flyback topology. This device is suitable for applications such as server, telecom and industrial boards, or any application that requires a low power or small form factor.

Overview

The MP174GJ-P is a non-synchronous/buck converter with wide range input and output capability, making it suitable for both AC-DC and DC-DC applications. The PWM section delivers up to 15W of output power using its own internal power MOSFET. It has a built-in soft-start with 50ms transition time and a start-up current of 0.35A, making it ideal for low power applications. The internal compensation is tailored for applications with a wide input voltage range and an output current range from 0.3A up to 8A. It also features an internal on-board voltage reference generator for compensated voltage regulation.

Features

• Wide range input voltage range with non-synchronous buck conversion
• On-board voltage reference generator
• Low start-up current – 0.35A
• Internal soft-start with 50ms transition time
• Auto-mode with support for both forward and flyback topologies
• Programmable over voltage protection (OVP) and short-circuit protection (SCP)
• High efficiency – up to 97%

Application

The MP174GJ-P is suitable for applications such as servers, telecom and industrial boards, or any application that requires a low power or small form factor. It is ideal for applications that require a wide input voltage range and conversion to either a forward or flyback topology. An example of such an application would be to generate 3.3V and 2.5V rails from 12V input. The MP174GJ-P can deliver up to 15W of output power using its own internal power MOSFET.

Working Principle

The MP174GJ-P operates in either a buck or a flyback topology, depending on the on-board Mode pin setting. In the buck topology, it uses a step-down voltage regulator to generate a stable output voltage. In the flyback topology, it functions as a synchronous boost converter, which generates a higher output voltage than the input voltage. The output voltage is regulated by an onboard voltage reference generator that is trimmed for accuracy.

When in buck mode, the MP174GJ-P regulates the output voltage by sensing the output supply to ensure it remains within a predetermined range. The precise output voltage is set by the level of the compensation voltage, which is generated by an on-board voltage reference generator. The reference voltage is further trimmed for accuracy by a set of fine-tune pins.

When in flyback mode, the MP174GJ-P regulates the output voltage by transferring energy between inductors. The precise output voltage is set by the ratio of two transformers, which is programmed using the “mode” pin. The on-board voltage reference generator is used to ensure the output voltage remains within a predetermined range.

The MP174GJ-P incorporates protection features such as over-voltage protection (OVP) and short-circuit protection (SCP) to ensure a safe and reliable operation. OVP is achieved by sensing the output supply and activating an internal switch to shut off the output. In addition, the short-circuit protection will shut down the power supply automatically if an over-current condition is detected.