d _ CTM

CD

DELAY_CTM

t

C

X

=

´

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SLUSA15C – JUNE 2010 – REVISED NOVEMBER 2010

www.ti.com

CELL CONNECTION SEQUENCE

NOTE

The recommended cell connection sequence begins from the bottom of the stack, as follows:

1. GND

2. VC4

3. VC3

4. VC2

5. VC1

While not advised, connecting the cells in a sequence other than that described above does not result in errant

activity on the OUT pin. For example:

1. GND

2. VC4, VC3, VC2, or VC1

3. Remaining VCx pin

4. Remaining VCx pin

5. Remaining VCx pin

CUSTOMER TEST MODE

Customer Test Mode (CTM) helps to greatly reduce the overvoltage detection delay time and enable quicker

customer production testing. This mode is intended for quick-pass board-level verification tests, and, as such,

overvoltage thresholds are to be tested, use the standard delay settings that are intended for normal use.

To enter CTM, VDD should be set to approximately 9.5 V higher than VC1. When CTM is entered, the device

thereby reducing the delay time during an overvoltage condition. The CTM overvoltage delay time is similar to

the equation presented in PROTECTION (OUT) TIMING AND DELAY TIME CAPACITOR SIZING with the

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 (VC1–VC2), (VC2–VC3), (VC3–VC4), and (VC4–GND).

Stressing the pins beyond the rated limits may cause permanent damage to the

device.

To exit CTM, power off the device and then power it back on.

functionality is exercised during protection testing. This can be accomplished by shorting the CD pin to GND. If

inaccurate.

8

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