5 BQ76922EVM Circuit Module Use
The BQ76922 circuit module contains the BQ76922 IC and related circuitry to demonstrate the features of the
IC. Surface mount FETs are provided for the high current path. A thermistor provides temperature sensing on the
board. Other components provide support for the IC and connections to the board. Basic operation is described
in the
. For details of the circuit, refer to the
5.1 Cell Simulator
The EVM includes a resistive cell simulator made up of 200-Ω series resistors. The taps of the resistor network
are connected to the cell inputs using shunts on the J16 header. BAT- is always connected to the resistor divider
network. Installing a shunt on the top cell location connects the top cell input to the resistor divider to provide
simulated voltages for the other cell inputs. If the shunt is not installed on the top cell position of the header all
lower inputs are pulled to VSS. Installing shunts for the lower cell positions connects the input to the simulated
voltage. There is no indication of the cell simulator connection, the user must be aware of the shunt installation.
5.2 Evaluating with Load Current
With the BQ76922 configured and the FETs enabled discharge current can be demonstrated by attaching
suitable resistors or a DC load at the PACK terminals as shown in
.
DC Power Supply
+ -
Install cell
simulator shunts
Position shunts
to “INT”
DC Load
+ -
Figure 5-1. Evaluating with Load Current
5.3 Evaluating Charge and Discharge Currents
Bipolar power supplies source or sink currents to maintain the set voltage. When bipolar supplies are available,
they may be used for both the battery and pack side of the board to allow charge and discharge currents without
re-connecting the equipment. Be sure to set the supplies appropriately to prevent exceeding the ratings of the
EVM.
BQ76922EVM Circuit Module Use
14
BQ76922EVM Evaluation Module
SLVU957A – SEPTEMBER 2019 – REVISED NOVEMBER 2021
Copyright © 2021 Texas Instruments Incorporated