Power Supply Filter Unit (Pow320); Input Filter; Battery Alarm; Battery Distribution And Presence Sensors - Alcatel 1850 TSS-320 Technical Handbook

4.3 Power supply filter unit (POW320)

This unit may be considered as an interface between the input battery coming from the TOP RACK UNIT
and the backplane in order to supply all the boards of the subrack.
Besides it supplies two "Auxiliary voltages": 3.6V and 5.3V (see the block diagram Figure 112. on page
174).
On the sub-unit POW320 power supply main board we can find the following functions:
–

Input filter

– Battery distribution
– Battery alarms (battery missing and And of batteries
– Presence sensors
– Card missing
– By-pass for Access battery
– Power monitoring
– 2M/bit terminations
– Spider
On the sub-unit POW320 daughter board we can find the following functions:
– Input power stage for DC/DC converters
– DC/DC converters
– Step-down
4.3.1 Input filter
An EMI filter (Refer to Figure 112. on page 174) used on the power line is basically a low pass filter that:
– Prevents the entry of high frequency interference carried by the DC power line into the equipment
– Prevents the exit of interference energy generated within the protected equipment into the DC power
line.

4.3.2 Battery alarm

This circuit is connected before fuses in order to monitor the presence or absence of the input battery. The
relative alarm is managed by SPIDER and "Battery alarms management block".

4.3.3 Battery distribution and presence sensors

This bock distributes the input battery towards backpanel and all the boards. Each line foresees a fuse
("over-voltage and over-current protection" block in Figure 112. on page 174) both on positive line and
negative line.
Fuses are fitted on each line in order to prevent a failed backpanel from shorting the input bus.
Technical Handbook Common
Unit Descriptions
Alcatel 1850 TSS-320 Rel. 1.1
8DG 07734 AAAA Edition 01 171/270