ACT8600 datasheet(49/50 Pages) ACTIVE-SEMI

49 / 50 page

ACT8600

Rev 3, 15-Nov-12

Innovative Power

ActivePMU

TM and ActivePathTM are trademarks of Active-Semi.

2CTM is a trademark of NXP.

- 49 -

www.active-semi.com

temperature of the battery pack by injecting a 100μA

(typ) current into the thermistor (via the TH pin) and

sensing the voltage at TH. The voltage at TH is

continuously monitored, and charging is suspended

if the voltage at TH exceeds either of the internal

VTHH and VTHL thresholds of 0.5V and 2.5V,

respectively.

The net resistance (from TH to GA) required to cross

the thresholds are given by:

100μA × RNOM × kHOT = 0.5V → RNOM × kHOT ≈

5kΩ

100μA × RNOM × kCOLD = 2.5V → RNOM ×

kCOLD ≈ 25kΩ

where RNOM is the nominal thermistor resistance at

room temperature, and kHOT and kCOLD represent

the ratios of the thermistor's resistance at the

desired hot and cold thresholds, respectively, to the

resistance at 25°C.

The status of the battery temperature pin may be

read at any time by reading the TEMPDAT[-] bit,

where a value of 1 indicates that battery temperature

is within the valid range, and a value of 0 indicates

that battery temperature has exceeded either of the

thresholds.

Figure 7:

Simple Configuration

ACT8600 Datasheet(PDF) 49 Page - Active-Semi, Inc