STMicroelectronics PM6644 350 mA Adjustable Step-Down Regulator Datasheet

The PM6644 is a 350mA valley current limit step-down regulator capable of delivering an adjustable output voltage in the range between 0.9 V and 8 V.

Brand: STMicroelectronics
Category: Other Electronics
Document type: Datasheet
Language: English
Pages: 35
File format: PDF
File size: 2.9 MB
Published: 10 August, 2012
Updated: 30 September, 2023
MD5 checksum: FF266E415B4317F643BCE59863D7D562
PDF: STMicroelectronics PM6644 350 mA Adjustable Step-Down Regulator Datasheet PDF

About this manual

The PM6644 is a step-down regulator designed for networking, portable, microcontroller, and industrial power supply applications. It features a constant-on-time (COT) architecture for fast load transient response and includes a pulse skipping mode to improve efficiency at light loads. The device offers a programmable switching frequency ranging from 200 kHz to 600 kHz via an external resistor.

What's inside

Simplified application schematic
Pin description
Absolute maximum ratings
Electrical characteristics
Output voltage set-up
Constant-on-time control
Current sensing and current limit
Fault management
External component selection
Package mechanical data

Specifications

Input voltage range	4.5 V to 25 V
Output voltage (fixed)	3.47 V
Output voltage (adjustable)	0.9 V to 8 V
Valley current limit	350 mA
Switching frequency range	200 kHz to 600 kHz
Package type	DFN10 3x3

Frequently asked questions

What is the output voltage range for the PM6644?

The output voltage is adjustable between 0.9 V and 8 V, or can be set to a fixed value of 3.47 V.

How is the switching frequency programmed?

The switching frequency can be adjusted from 200 kHz to 600 kHz through a simple external resistor connected to the TON pin.

Does the PM6644 support pulse skipping mode?

Yes, it supports pulse skipping mode at light loads to increase efficiency.

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