X3100 Datasheet, PDF (27/40 Pages) Xicor Inc. – 3 or 4 Cell Li-Ion Battery Protection and Monitor IC

X3100/X3101 – Preliminary Information
Write Configuration Register (WCFIG)
The Write Configuration Register (WCFIG) instruction
updates the static part of the Configuration Register.
These new values take effect immediately, for example
writing a new Over-discharge voltage limit. However, to
make these changes permanent, so they remain if the
cell voltages are removed, an EEWRITE operation to
the EEPROM array is required following the WCFIG
command. This command is shown in Figure 16.
Write Control Register (WCNTRL)
The Write Control Register (WCNTRL) instruction
updates the contents of the volatile Control Register.
This command sets the status of the FET control pins,
the cell balancing outputs, the current sense gain and
external entry to the sleep mode. Since this instruction
controls a volatile register, no other commands are
required and there is no delay time needed after the
instruction, before subsequent commands. The
operation of the WCNTRL command is shown in
Figure 17.
Figure 16. Write Configuration Register (WCFIG) Operation Sequence
CS
SCK
SI
0123456789
20 21 22 23
WCFIG Instruction
(1 BYTE)
Configuration
Register Data
15 14
3210
(2 BYTE)
High Impedance
SO
Figure 17. Write Control Register (WCNTR) Operation Sequence
CS
SCK
SI
SO
Control
Bits
0123456789
18 19 20 21 22 23
WCNTR Instruction
(1 Byte)
High Impedance
Control
Register Data
15 14
5 4 3 21 0
(2 Byte)
Old Control Bits
New Control Bits
REV 1.1.8 12/10/02
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Characteristics subject to change without notice. 27 of 40