si3200-x-gs Silicon Laboratories, si3200-x-gs Datasheet - Page 30

• Manufacturer Part Number: si3200-x-gs
• Description: Dual Programmable Cmos Slic With Line Monitoring
• Manufacturer: Silicon Laboratories

Si3232
When generating a high-voltage ringing amplitude using the Si3220, the power dissipated during the OHT state
typically increases due to operating from the ringing battery supply in this mode. To reduce power, the Si3232/
Si3200 chipset provides the ability to accommodate up to three separate battery supplies by implementing a
secondary battery switch using a few low-cost external components as illustrated in Figure 13. The Si3232’s
BATSEL pin is used to switch between the V
internal to the Si3200. The Si3232’s GPO pin is used along with the external transistor circuit to switch the V
rail (the ringing voltage battery rail) onto the Si3200’s VBAT pin when ringing is enabled. The GPO signal is driven
automatically by the ringing cadence provided that the RRAIL bit of the RLYCON register is set to 1 (signifying that
a third battery rail is present).
30
806 kΩ
Figure 12. External Battery Switching Using the Si3232 and Si3200
SVBAT
V
BLO
V
BHI
Sensing
Battery
Circuit
VBATH
VBATL
VBAT
Si3232
BHI
Preliminary Rev. 0.96
(typically –48 V) and V
Si3200
Control
Battery
Logic
Linefeed
Circuitry
BLO
BATSEL
(typically –24 V) rails using the switch
Battery
Control
Select
BATSEL
40.2 kΩ
BRING