Applications

Automotive On Board Charger

1. Overview

ICs ideal for On Board Chargers

The On Board Charger (OBC) converts AC power supplied from either a household outlet or charging station into DC power, which charges the high-voltage battery, drive for EV and PHEV.
The On Board Charger (OBC) uses low on-resistance Si IGBTs or SiC MOSFETs to reduce conversion loss. The on-resistance has the characteristic to drop as the gate voltage rises so it is recommended to design a gate drive circuit using, for example, an Si IGBT with a high voltage of around 15V or an SiC MOSFET with a high voltage of around 18V.
ABLIC has a lineup of LDOs that can output a high voltage required for the gate driver circuit. In addition, our lineup offers LDOs with built-in watchdog timers for monitoring MCUs, and operational amplifiers ideal for current monitoring of PFC. ABLIC undoubtedly provides ICs ideal for On Board Chargers (OBC).

2. Block Circuit

Click each product group for more ​product information.

HV Battery 400V / 800V DC/DC Primary AC PFC DC/DC Secondary 12V Battery 15V 5V Isolated Gate Driver 15V 5V Isolated Gate Driver MCU ・・ ・・ LDO LDO LDO LDO OPAMP LDO VD WDT Flyback Controller Flyback Controller

*VD: Voltage detector (Reset IC) *LDO: Low-dropout regulator *WDT: Watchdog timer

3. ICs ideal for On Board Chargers

Product Recommended product Applications and Features
LDO Regulator
(Linear Regulator)
S-19212 For use in gate driver circuits. The output voltage can be set between 2.5 to 16V.
LDO Regulator
(Linear Regulator)
S-19213 For use in gate driver circuits. The output voltage can be adjusted between 1.8 to 30V using an external resistor.
Flyback Controller
(Switching regulator)
S-19990 Low voltage operation (from 3.0V). 60μA quiescent current. The industry's smallest package.

App note

Watchdog Timer S-1951x With reset and LDO regulator functions. Current consumption of 3.0µA.
Operational amplifier S-19630A High-accuracy current detection. 36V operation, Rail-to-Rail input/output, low offset voltage of 50μV.
Operational amplifier S-19611A High-accuracy current detection. 5.5V operation, Rail-to-Rail input/output, low offset voltage of 100μV.

4. Features