Power Supply; Schematic Diagram Of The Power Supply - Motorola 56F8346 User Manual

2.11 Power Supply

The main power input to the 56F8346EVM, +12V DC at 1.2A, is through a 2.1mm coax
power jack. This input power is rectified to provide a DC supply input. This allows a user
the option to use a +12V AC power supply. A 1.2Amp power supply is provided with the
56F8346EVM; however, less than 500mA is required by the EVM. The remaining current
is available for custom control applications when connected to the Daughter Card
connectors. The 56F8346EVM provides +5.0V DC regulation for the CAN interface and
additional regulators. The 56F8346EVM provides +3.3V DC voltage regulation for the
hybrid controller, memory, D/A, ADC, parallel JTAG interface and supporting logic; refer
to Figure 2-11. Additional voltage regulation logic provides a low noise +3.0V DC
voltage reference to the hybrid controller's A/D V
V voltage can be provided by the +3.3V A supply on the board by removing U15 and
REFH
adding a 10 ohm resistor at R83. A jumper, JG10, and resistor, R2, is provided to allow the
analog and digital grounds to be isolated on the 56F8346EVM board. This allows the
analog ground reference point to be provided on a custom board attached to the
56F8346EVM's Daughter Card connectors. By removing R2, the AGND reference is
disconnected from the 56F8346EVM's digital ground. By placing a jumper in JG10, the
AGND is reconnected to the 56F8346EVM's digital ground. Power applied to the
56F8346EVM is indicated with a Power-ON LED, referenced as LED13. Optionally, the
user can provide the +2.5 DC voltage needed by the hybrid controller's core on connector
J22 and disable the on-chip CORE voltage regulator by moving the resistor at R97 to R96.
Additonally, four zero ohm resistors or shorting wires must be added at R92, R93, R94
and R95 to allow the external +2.5V DC to pass to the 56F8346.
P3
+12V DC/AC
Bridge
Input
Rectifier
Figure 2-10. Schematic Diagram of the Power Supply
2-16
Freescale Semiconductor, Inc.
+5.0V
Regulator
+2.5V DC
Ext In
Power ON
56F8346EVM User Manual
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. Optionally, the device's A/D
REFH
+5.0V DC
Power
Condition
+3.3V DC
+3.3V
Regulator
J22
R92-R95
1
2
+3.3V +3.3VA DC
Regulator
10 Ω
R83
U15
+3.0V A DC
+3.0V
Regulator
CAN
56F8346
V & PLL
DD_IO
56F8346EVM
Parts
56F8346
V Core
DD
56F8346
ADC
A
56F8346
V
REFH
MOTOROLA