Operation
8
SLUUBI1A – October 2016 – Revised July 2018
Copyright © 2016–2018, Texas Instruments Incorporated
bq34110EVM-796 Evaluation Module
3.2.1
Cell Configuration
The bq34110 operates in one of two modes for measuring battery voltage. Place jumpers on the J2 and
J5 headers to select the mode of operation. See the
section.
For packs where the stack voltage is less than 5 V:
•
Enable Calibration Mode on the device by pressing the
CAL_TOGGLE
button on the Commands
panel. Verify that the
CAL_EN
flag is set in the
Manufacturing Status
register.
•
Update the
Flash Update OK Voltage
parameter on the Data Memory
Configuration
screen to
100mV (default is 2.8V). This parameter prevents flash updates when the measured voltage is below
this setting. This can later be updated to an appropriate voltage once the dividers are configured.
•
Set the
Number of Series Cells
parameter to the appropriate value on the Data Memory
Configuration
screen.
•
Reset the gauge using the
RESET
button on the
Commands
panel.
•
Calibrate the stack voltage. See the
section.
NOTE:
The EVM can support single cell applications, where the cell voltage can drop below 2.5 V,
by providing an external 3.3-V supply to power REGIN. For voltages below 2.5V, remove the
jumper from J2 – pins 3 and 4 (upper
≤
5-V jumper location) and apply a 3.3-V supply to the
REGIN test point.
For packs where the stack voltage is greater than 5 V:
•
Enable Calibration Mode on the device by pressing the
CAL_TOGGLE
button on the
Commands
panel. Verify that the
CAL_EN
flag is set in the
Manufacturing Status
register.
•
Update the
Flash Update OK Voltage
parameter on the Data Memory
Configuration
screen to
100mV (default is 2.8V). This parameter prevents flash updates when the measured voltage is below
this setting.
•
Set the
VEN_EN
bit to “1” in the
Pin Control Config
in Data Memory on the
Settings
screen. This
enables the external voltage divider on the EVM and disables the internal voltage divider. The VEN pin
will pulse to enable the external resistor divider only during a voltage measurement to save power.
•
Set the
Number of Series Cells
parameter to the appropriate value on the Data Memory
Configuration
screen.
•
Set the
Voltage Divider
parameter in Data Memory on the
Calibration
screen. This value should be
set based on the external resistor divider setting. (For example, use ~19,200 when the J5 header is set
to the 16V setting which divides the BAT+ voltage by 19.2).
•
Reset the gauge using the
RESET
button on the
Commands
panel.
•
Calibrate the stack voltage. See the
section.