Kontron AT8402 User Manual page 52

AT8402
3.1.9.2 Power Supply Mezzanine
The Filter, the Hot-Swap-Controller, the Hold Over circuit and the Quarter-Brick are situated on
the Power Supply Mezzanine Module. The Power Supply Mezzanine is connected to the Car-
rier Board with the J4 connector.
3.1.9.3 Power Distribution
The 48 Volts are supplied by the backplane via two independent rails, primary (A) and second-
ary (B). The rails are mixed using power Schottky rectifiers. A 7A fuse protects each -48V line
and a 10A fuse protects each RTN line. A hot swap controller enables the 48V power to the
board.
On the mezzanine module, a quarter brick DC/DC converter transforms the 48 Volts to second-
ary 12 Volts for payload supply and 3.3 Volts for management supply.
Two further management voltages (5V and 1.8V) and six payload voltages (1.0V, 1.2V, 1.25V,
1.5V, 2.5V and 3.3V) are generated by point of load converters from the secondary voltages.
The management (or suspend) power is present once the board is connected to the backplane.
It supplies the IPMI part which in turn controls the payload power. The various payload voltages
are sequenced. The initial power up sequence is as follows (1ms delay between steps):
1. V_1V0
2. V_VCORE, V_1V5
3. V_3V3
4. V_2V5
5. V_1V25
6. V_1V2
The power down sequence is performed in reversed order with a 1ms delay.
3.1.9.4 Power Supply AMCs
Each AMC has its own power supply. The 12V payload power is generated by a hot swap con-
troller and for the 3V3 management power a current limit switch is used. The maximum power
dissipation for an AMC is 60W.
For further details please refer the AMC Specification.
3.1.9.5 Power Supply RTM
The RTM has its own power supply. The 12V payload power is generated by a hot swap con-
troller and for the management power a current limit switch is used. The maximum power dis-
sipation for an RTM is 10W.
For further details please refer the PICMG 3.0 standard.
Hardware Description
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