Atmel AVR365
3
8336A-AVR-03/12
Figure 2-2.
The SCH of polarity circuit.
2.1.3 Pre-charge circuit
The Atmel ATBM302 supports two pre-charge methods: Internal pre-charge and
External pre-charge.
If external pre-charge is selected, the external PCH pads in BM303 should be
connected as shown in
, and the parameter ‘PrechargeCircuitSel’ in SMBus
should be configured to 1.
If internal pre-charge is selected, the two pads must be divided. The charger must in
this case control the pre-charge current – either by sensing the voltage level or by
receiving commands from the BM303 to control the current. The parameter
‘PrechargeCircuitSel’ in SMBus must be configured to 0.
Figure 2-3.
Pre-charge switch pad.
2.1.4 LED indication
The LEDs in the battery pack is used to indicate the capacity of battery. When the
switch is pushed down, the LEDs will be on for about three seconds. If the capacity is
from 0% to 20%, LED0 will be on, if battery capacity is from 20% to 40%, LED0 and
LED1 will be on etc.
2.1.5 Fuse blowing
In the BM302 the fuse is not mounted on the PCB, pin 1 and pin 3 of fuse are
connected by polygons. The voltage in the PF test point can be monitored to check if
fuse is blown.
To mount a fuse, please cut the polygon in black rectangle first.
