100

VCELL1

VCELL3

VCELL2

OUT

VDD

VSS

0. 1 µF

0.1µF

0.1µF

0.1µF

1k

1k

1k

bq2945xy

Pack +

Pack –

V3

V2

V1

PWRPAD

100

VCELL1

VCELL2

OUT

VDD

VSS

0.1

0.1µF

1k

1k

bq2945xy

Pack +

Pack –

V3

V2

V1

PWRPAD

µF

0.1µF

VCELL1

VCELL3

VCELL2

OUT

VDD

VSS

bq2945xy

Pack +

Pack–

V3

V2

V1

PWRPAD

bq294502, bq294504, bq294512, bq294515

bq294522, bq294524, bq294532, bq294562

bq294572, bq294582, bq294592

SLUSAJ3C – SEPTEMBER 2011 – REVISED MAY 2012

www.ti.com

APPLICATION INFORMATION

Figure 7. Application Configuration

Changes to the ranges stated in Table 1 will impact the accuracy of the cell measurements. Figure 7 shows each

external component.

Table 1. Parameters

PARAMETER

External Component

MIN

NOM

MAX

UNIT

Voltage monitor filter resistance

RIN

900

1000

1100

Ω

Voltage monitor filter capacitance

CIN

0.01

0.1

µF

Supply voltage filter resistance

RVD

100

1K

Ω

Supply voltage filter capacitance

CVD

0.1

µF

APPLICATION SCHEMATIC

Figure 8. 3-Series Cell Configuration with Fixed

Figure 9. 2-Series Cell Configuration with Internal

Delay

Fixed Delay

CUSTOMER TEST MODE

Customer Test Mode (CTM) helps to reduce test time for checking the overvoltage delay timer parameter once

the circuit is implemented in the battery pack. To enter CTM, VDD should be set to at least 10 V higher than V3

(see Figure 10). The delay timer is greater than 10 ms, but considerably shorter than the timer delay in normal

operation. To exit Customer Test Mode, remove the VDD to VC3 voltage differential of 10 V so that the decrease

in this value automatically causes an exit.

CAUTION

Avoid exceeding any Absolute Maximum Voltages on any pins when placing the part

into Customer Test Mode. Also avoid exceeding Absolute Maximum Voltages for the

individual cell voltages (V3–V2), (V2–V1), and (V1–VSS). Stressing the pins beyond

the rated limits may cause permanent damage to the device.

8

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