Huawei ATN 950B Hardware Description page 32

ATN 950B Multi-service Access Equipment
Hardware Description
Figure 3-2 Block diagram for the working principle of the AND1FAN
Start-delay/Combiner Module
This module provides start delay to the combined two 12 V power supplies and protecting fans
against overcurrent.
Filter Module
This module filters the LC low frequency to enhance the EMC feature of the system.
Communication Unit Module
This module reports the board manufacturing information, PCB version, and environment
temperature information. In addition, this module provides 12 V power shut signals to the start-
delay module.
Intelligent Fan Speed Adjustment Module
This module reports information about the fan rotating speed to the AND1CXPA/
AND1CXPB and adjusts the fan rotating speed according to the pulse-width modulation (PWM)
signals received from the AND1CXPA/AND1CXPB.
Board In-Position Module
This module reports the board in-position signals to the AND1CXPA/AND1CXPB.
Issue 03 (2012-07-23)
Fans x 6
12 V
12 V
12 V
Communication unit
PWM signals
Intelligent fan speed
adjustment module
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Start-delay
Filter module
12 V power shut signals
Inter-board communication bus
module
Fan rotating speed signals
Fan speed
reporting module
PWM driver
module
Board in-position Fan in-position signals
module
3 Heat Dissipation System
12 V
Combiner
Combiner/
12 V
soft-start module
CXP
CXP
CXP
CXP
CXP
CXP
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