Texas Instruments bq24010/2 User Manual

Page 11

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Test Procedure

2-3

Test Summary

In place of a battery, a source meter that can sink current can easily be
adjusted to test each mode.

Another way to briefly see each mode on a scope is to connect a 1-mF
capacitor and a 10-k

resistor on the output in place of a battery to observe

the power-up and cycling between voltage regulation and fast charge via the
refresh threshold.

The difference between the bq2401x parts, where x is a 0 or 2, is as follows:
The functions on the 0 part are power good output (PG) for pin 7 and
temperature sense Input (TS) for pin 8. On part 2, pin 8 is charge enable (CE).
From the factory, the CE pin has a pulldown resistor and the TS pin is set at
50% of V

CC

, where applicable. These signals, if applicable, are available at the

connectors for external control.

Note:

Because of the battery-detection circuit, it is not possible to switch-in static
load resistors to jump between regulation and constant-current modes. An
alternate procedure described below uses a dynamic load to replace the
battery circuit. That procedure allows testing of each mode.

This is an alternative way of testing the EVM using a dynamic load board in
place of a battery. The circuit is adjusted to work with the displayed parts and
their inherent thresholds. The sequence of the test procedure is important
because of the active battery-detection circuit, refresh feature, and precharge
and fast-charge current levels. (Switching load in or out has different results
in different modes.) No damage should occur, but results might be different
than anticipated if procedure is altered.

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