Technical data

Functional Description
MVME2502 Installation and Use (6806800R96B)
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4.14 Reset/Control CPLD
The CPLD provides the following functions:
 Power control and fault detection
 Reset sequence and reset management
 Status and control registers
 Miscellaneous control logic
 Watchdog timer
 32-bit Tick Timer
 Clock generator
 Switch decoder and LED controller
4.15 Power Management
The MVME2502 backplane is utilized to derive +3.3V, +2.5V, +1.8V, +1.5V, +1.2V, +1.05V
voltage rail. Each voltage rail is controlled by the CPLD through an enable pin of the regulator,
while the output is monitored through power good signal. If a voltage rail fails, the CPLD will
disable all of the regulators. To restart the system, the chassis power switch must be power-
cycled.
4.15.1 Onboard Voltage Supply Requirement
The onboard power supply is considered to be out of regulation if the output voltage level is
below the minimum required power or goes beyond the maximum.
Table 4-5 Voltage Supply Requirement
Voltage Rail
Voltage Rail Requirement
Minimum Maximum
+3.3 V 3.15 V 3.45 V
+2.5 V 2.375 V 2.625 V
+1.8 V 1.7 V 1.9 V