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Fan Trays
19
R1.0, October 2018
6.3 Fan Tray Block Diagram
Figure 14: Fan Tray Block Diagram
12711838
PEM present
3.3 V
Hot Swap
Controller
Current
Limiter
RS232
LM75
Hot Swap Button
SEEPROM
local I²C Bus
I2C Buffer
LM75
Exhaust/Intake
IPMB_A
I2C Buffer
Enable
IPMB_B
I2C Buffer
Enable
Watchdog
PWM
48 V to 3.6 V
DC/DC
Converter
T
acho
48V
24V
PWM
T
acho
GND (Fan Tray present)
NSEAT (Short Pin)
HA0
HA1
Air Filter present
GND
GND
JTAG
Only in lower Fan Tray
VRTN_B
-
48V_A
-
48V_B
VRTN_A
Fuse Monitor
48V
24V
48V
24V
Hot Swap
Controller
PWM
T
acho
48V
24V
VRTN_B
-
48V_A
-
48V_B
VRTN_A
Fuse Monitor
48V
24V
48V
24V
Connector
LM75 LM75
MAJ
MIN
CRIT
Fault
OK
HS
ALARM SILENCE
Critical Alarm
Major Alarm
Minor Alarm
Power Alarm
Minor Clear
Major Clear
red
red
amber
red
green
blue
1
8
9
15
LED
Buffer
LED
Buffer
Serial Console of Shelf Manager 1
Serial 1
Serial 2
Serial Console of Shelf Manager 2
ESD
protection
ESD
protection
IPM
Controller
3.6 V