Texas Instruments bq77915EVM-014, Руководство пользователя

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Additional Evaluation Setups
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6 SLUUBU2B – March 2018 – Revised August 2018
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bq77915 3-5S Low Power Protector Evaluation Module
16. Remove the load resistor on the PACK terminals. Observe that the pack voltage returns to the supply
voltage because undervoltage recovers on the installed part configuration with both voltage and load
removal.
17. Disable the power supply and disconnect, if complete.
3 Additional Evaluation Setups
CAUTION
The bq77915 EVM does not contain capacitors on the input or output current
paths to dampen transients. Be sure to use appropriate transient suppression
to avoid damage to the board from cable or equipment transient responses
during evaluation.
3.1 Operation With Charge and Discharge Currents
If bipolar power supplies are available, current control can be demonstrated through the board in both
directions, see
Figure 2 . A battery voltage in range must be applied to the BATT side of the EVM for
operation. The instrument on the PACK side can be used as a load if it is set to a lower voltage than the
battery side or as a charger if set to a higher voltage. Additional equipment can be used to adjust the
voltage across the individual input resistors to simulate different cell voltages.
Figure 2. Bipolar Operation
Operation can also be demonstrated with conventional supplies and loads. Connect and operate the
equipment within its performance limits.
3.2 Reducing the Cell Count
The bq77915 EVM may be modified to provide monitoring of three or four cells. Figure 3 shows a concept
of simple three-cell evaluation. Cells are connected from the bottom up with unused top-cell inputs
connected to the top cell at J2. While this is not the direct IC pin connection shown in the data sheet, it will
work for general evaluation. The CCFG pin must also be connected to AVDD or GND to select monitoring
of three or four cells. This can be done by adding a jumper at the J8 pattern between pins 1 and 2 or 2
and 3 as desired. If the board will be used for further evaluation, be sure to remove the jumper at J8 after
the reduced cell test.