4 BQ76942 Circuit Module Use
The BQ76942 circuit module contains the BQ76942 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
section. For details of the circuit, refer to the
4.1 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 J19 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 will connect the input to the simulated
voltage. There is no indication of the cell simulator connection, the user must be aware of the shunt installation.
4.2 Evaluating with Load Current
With the BQ769x2 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
DC Load
+ -
Figure 4-1. Evaluating with Load Current
4.3 Evaluating Charge and Discharge Currents
Bipolar power supplies will source or sink current 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.
BQ76942 Circuit Module Use
SLUUC32A – NOVEMBER 2019 – REVISED OCTOBER 2020
BQ76942 Evaluation Module
17
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