The RT4813 is a Boost converter with the input voltage range from 1.8V to 5.5V and provide an average output current limit range from 0.55A to 3.1A. This document explains the function and use of the RT4813 evaluation board (EVB), and provides information to enable operation, output voltage setting of the evaluation board.

Introduction

General Product Description

The RT4813 allows systems to take advantage of new battery chemistries that can supply significant energy when the battery voltage is lower than the required voltage for system power ICs. By combining built-in power transistors, synchronous rectification, and low supply current; this IC provides a compact solution for systems using advanced Li-Ion battery chemistries.

The RT4813 is a boost regulator designed to provide a minimum output voltage from a single-cell Li-Ion battery, even when the battery voltage is below system minimum. In boost mode, output voltage regulation is guaranteed to a maximum load current of 3.1A. Quiescent current in Shutdown Mode is less than 1µA, which maximizes battery life.

• CMCOT Topology and Small Output Ripple when VIN Close VOUT Voltage
• Operates from a Single Li-ion Cell : 1.8V to 5.5V
• Adjustable Output Voltage : 1.8V to 5.5V
• PSM Operation
• Up to 96% Efficiency
• Input Over Current Limit
• Input/Output Over Voltage Protection
• Programmable Average Output Current Limit Range : 3100mA to 550mA
• Internal Compensation
• Output Discharge
• Output Short Protection
• True Load Disconnect

Key Performance Summary Table

Headers Description and Placement

Carefully inspect all the components used in the EVB according to the following Bill of Materials table, and then make sure all the components are undamaged and correctly installed. If there is any missing or damaged component, which may occur during transportation, please contact our distributors or e-mail us at evb_service@richtek.com.

Test Points:

The EVB is provided with the test points and pin names listed in the table below.

Power-up & Measurement Procedure

1. Connect input voltage (1.8V < V_IN < 5.5V).

2. To use a jumper at “H” option to tie EN pin to input voltage VIN via JP1 or external voltage for enabling the device. Inversely, to use a jumper at “L” option to tie EN pin to ground GND for disabling the device.

3. To verify the output voltage V_OUT via the dividing resistors.

4. To connect an external load up to 1A and verify the output voltage and current.

I2C Register Setting

The register as the table shown can be programmed by a MCU through the dedicated I2C interface. The device slave address is 0x39.

EVB Schematic Diagram:

BOM:

PCB Layout:

Top View (1^st layer)

PCB Layout—Inner Side (2^nd Layer)

PCB Layout—Inner Side (3^rd Layer)

Bottom View (4^th Layer)