GE B30 Technical Reference Manual page 34

B30 Patient Monitor
Smart batteries, battery charger and PMC communicate via SMBus (System Management Bus).
It is a two-wire interface closely resembling I2C. Smart battery controls the charging and
calculates and stores the capacity information as well as other battery related data. Batteries
can be charged when external DC or AC/DC voltage is present.
Block diagram of the power supplies is represented in following
5V_PMC
PMC CPU
ON/STBY
SERIAL COMM.
ON/STBY CTRL
Figure 8
Battery charger
Battery charger is a Level 2 Smart Battery Charger. It communicates with the batteries and
PMC CPU via SMBus interface. The charger acts as an SMBus slave device that responds to
charging current and charging voltage values sent to it by a Smart Battery.
The charger includes an input current limiting feature. In a case where the input current
exceeds the limit, the charger reduces the output current to keep the input within the limit. The
currents of the MOD voltages (VMOD, I/O_VMOD) are taken through this current measurement
1-20
.
Document no 2044677-001
DC/DC BOARD FUNCTIONAL BLOCKS
AC / DC
15.9V
+/-2%
POWER
PATH
SWITCH
CIRCUIT
BREAKER
VSYS 9 - 16.2V
3.3V
BUCK
&
LOGIC
+3.3V
&
DC/DC board block diagram
2x BATTERY
EXTERNAL
10.8V Li-ION
DC
(9-12.6V)
10 - 16.5V
14.6V /
15.4V
2-LEVEL
SET_HI
BOOST
5V
BUCK
CIRCUIT
BREAKER
VSYS_OUT
+5V +5V_OUT
9 -16.2V
SMART
BATTERIES
= DC/DC-BOARD
POWER
PATH
SWITCH
SMART
BATTERY
CHARGER
(BUCK)
Boost converter Power source
15.4V (set_hi) @ EXTDC
14.6V @ Battery
passed by diode @ AC/DC
VBOOST 14.1 - 16V
CIRCUIT
BREAKER
VMOD
I/O_VMOD
13.8- 16V 13.8 -16V