Qorvo’s PMIC for In-vehicle Charging Integrates Analog and Power Functions

January 14, 2020 by Gary Elinoff

Qorvo claims that ACT475M is the industry’s first AEC-Q100-qualified PMIC DC-DC buck converter aimed at USB Type-C fast charging applications.

Qorvo, a manufacturer known for its RF solutions, has released, ACT475M, a power management IC (PMIC) built for fast in-vehicle charging of mobile phones, tablets, and laptops. Qorvo maintains that (PDF) ACT475M is the first device of its kind to integrate both the analog and power functions into a single power chip.


The ACT4751M. Image used courtesy of (PDF) Qorvo

This approach is said to save space, reduce the BOM count, increase reliability, and save development time. 


Input/Output Voltage and Other Specifications

The device can operate with input voltages ranging from 4.5V to 40V. In order to survive in the harsh automotive environment, Qorvo included built-in protection to allow the device to survive load-dump events of up to 48V. 

The ACT4751M can offer output voltages ranging from 3.0V to 24V in 23.5 microvolt steps. The output current can be varied from 0A to 4A in 256 steps. 

The unit switches from 460kHz to 2,250kHz. Spread spectrum operation enables non-interference with the AM radio band and the avoidance of noise peaks.


Block diagram of the ACT4751M

Block diagram of the ACT4751M. Image used courtesy of (PDF) Qorvo

The unit incorporates both high-side and low-side MOSFETs with 50 milliohms on resistances. This, in theory, increases efficiency and decreases power losses. 

In addition to the main output, the device also offers two additional power rails. There is a 5V, 350mA line powered by a mini-buck converter, and an LDO line offering from 0.9V to 4.0V at 20mA. 

The unit is controlled using an I2C interface.


USB Type C Charging in Today’s Automobiles

Because of their ability to impart lots of power quickly, high power USB Type-C ports are becoming ever more prevalent in a wide range of electronic devices. 

David Briggs, senior director of Qorvo's programmable power management business, has said that "The proliferation of connected car devices with advanced in-cabin infotainment systems demands more power ports at higher power levels. Qorvo's AEC-Q100 qualified power IC, ACT4751M, is a unique and easy-to-use step-down product that features the smallest size and highest efficiency on the market."


Meeting Industry Standards

The ACT4751M meets the Power Delivery 3.0 Programmable Power Supply (USB PD 3.0 PPS) specification. It also meets the CISPR 25 Class 3 standard for automotive EMI and is RoHS compliant.

The ACT4751M is available in a 32-pin 5mm x 5mm QFN package designed for dissipating heat.


Evaluation and Support Tools

In an effort to help OEMs bring their products to market more quickly, Qorvo offers reference designs certified for USB fast charging as per Qualcomm’s Quick Charge 3.0. 4, and 4+.

The company also offers an evaluation kit.


The ACT4751EVK1-101 evaluation kit
The ACT4751EVK1-101 evaluation kit. Image used courtesy of Qorvo


The ACT4751EVK1-101 evaluation kit includes a USB Dongle and a (ZIP) Graphical User Interface (GUI) for easy communication with the developer’s PC. 


Around the Industry

Texas Instrument’s (PDF) TPS2584x-Q1 is aimed at USB Type-A BC1.2 charging applications. The AEC-Q100 qualified buck converter offers works with inputs ranging from 4.5V to 36V and provides an output of 5V at 3.5A. 

The (PDF) ISL78083 from Renesas is designed to simplify the design of automotive camera systems. The unit is qualified to AEC-Q100, works with input voltages from 4.0V to 42V, and incorporates three buck converters and one boost converter.