MP2681B – CC/CV CONTROLLER WITH FULL PROTECTION

MP2681B Rev.1.0

www.MonolithicPower.com

11

12/22/2014

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2014 MPS. All Rights Reserved.

OPERATION

T1

+

Flyback

Primary

C

NTC

ID

...

Battery

Detection

Charge

On/Off

Control

Temperature

Sense

Current

Sense

Indication

Control

Core

Current

Reference

Voltage

Reference

CC/ CV

Control

Voltage

Sense

LED

To

Primary

BT+

BT-

Fixed

Pre-Charge

CR

Figure 1. Functional Block Diagram

Charge Voltage Setting

The MP2681B supports 3 different types of

battery configurations: 3S, 4S, and 5S using a

dedicated ID resistor pin. When a battery pack

configuration is detected through the ID resistor,

automatically the charge voltage is set internally;

different battery pack implementations require

different ID resistor values. The MP2681B ID is

connected to the ID resistor in the battery pack

and pulled up to LDO by a resistor (see Figure 2).

internal reference to figure out the inserted

battery configuration. As the battery changes

among the six pre-set configurations, the

MP2681B detects such conditions, and it

modifies automatically the resistor divider from

VDD (see Figure 3). Charge current, as well as

other charge parameters, change accordingly.

Figure 2

. Battery-Pack Pin Connection

Additionally, if the battery pack does not have an

ID resistor, the charge-termination voltage can be

configured by setting a dedicated voltage to ID

each battery configuration).