RT9535B

Copyright © 2016 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation.

DS9535B-04

February

2016

www.richtek.com

1

High Efficiency Switching Mode Battery Charger

General Description

The RT9535B is a PWM switch mode battery charger

controller to fast charge single or multiple Li-Ion, NiMH

and NiCd batteries, using constant current or constant

voltage control. Maximum current can be easily

programmed by external resistor. The constant voltage

output can support up to 22V with 0.5% accuracy.

A third control loop limits the input current drawing from

the adapter during charging. This allows simultaneous

operation of the equipment and fast battery charging

without over loading to the adapter.

The RT9535B can charge batteries from 2.5V to 22V

with dropout voltage as low as 0.4V. A logic output

indicates Li-Ion full charge when current drops to 17%

of the full-scale programmed charge current.

The RT9535B is available in the WQFN-24L 4x4

package.

Features



Fast Charging for Li-Ion, NiMH and NiCd Batteries



Adjustable Battery Voltages from 2.5V to 22V



High Efficiency : Up to 95%



Charging Current Programmed by Resistor



Precision 0.5% Charging Voltage Accuracy



Provide 5% Charging Current Accuracy



Input Current Limit Maximizes Charging Rate



500kHz Switching Frequency



Flag Indicates Li-Ion Charge Completion



Auto Shutdown with Adapter Removal



Only 10

A Battery Reverse Current when Idle

Applications



Notebook Computers



Portable Instruments



Chargers for Li-lon, NiMH, NiCd and Lead Acid

Rechargeable Batteries

Simplified Application Circuit

C2

RT9535B

V5V

BOOT

HSD

SW

SNSH

SNSL

BATT

SGND

VC

ISET

SS

VHH

VHH

NTC

PGND

M1

R5

C4

C5

R4

R3

R2

D2

D3

R9

C7

C8

D1

L1

RS3

RS2

RS1

C9

To VHH Pin

RF2

RF1

To VFB Pin

STATUS

GND

(Exposed Pad)

VFB

VFB

R1

VIN

EN

ACDRV

ACP

ACN

RS4

C1

R10

C3

C11

C6