DC Power Supply
+ -
Install cell
simulator shunts
Short
CELL15 to CELL14
and
CELL14 to CELL13
Figure 4-4. Example 14 Cell Simple Evaluation Configuration
When reducing the cell count with the top cell used, the resulting configuration of the BQ7718 secondary
protector does not match its data sheet configuration. While the circuit will typically function on the EVM, when
implementing a design the configuration of the data sheet is recommended.
4.6 Connecting Cells
The EVM is constructed with a single connection to the top and bottom of the cell stack. Cell voltage for these
cells is sensed on the board.
While the EVM has a place to mount an activated fuse, the pattern is shorted to allow easy evaluation without
the concern of activating the fuse. When connecting cells use a fuse in the current path and any other signal
path appropriate for your application.
The cell simulator provides resistors between the cell inputs. When the cell simulator shunts are installed, these
resistors will load the cells and divide the voltage to any unconnected inputs as cells are connected. If desired,
the cell simulator shunts can be installed during cell connection and removed after cell connection. The shunts
must be removed after connection of cells or the cells will be discharged by the constant drain of the cell
simulator resistors.
BAT- is the reference voltage for the IC and should be connected first. After BAT- cells may be connected in any
order. Cell connection from the bottom up minimizes the voltage step size applied to the board. Recommended
connection sequence for the EVM when connecting cells is bottom up:
1. Connect BAT–
2. Connect cells bottom up; CELL1, CELL2, CELL3 ...
3. Be sure the cell simulator shunts are removed
shows an example connecting cells with an EVM configuration reduced to 15 cells.
BQ76952 Circuit Module Use
20
BQ76952 Evaluation Module
SLUUC33A – NOVEMBER 2019 – REVISED OCTOBER 2020
Copyright © 2020 Texas Instruments Incorporated