Datasheet

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DP83849C
1.8 Special Connections
1.9 Power Supply Pins
Signal Name Type Pin # Description
RBIAS I 32 Bias Resistor Connection: A 4.87 kΩ 1% resistor should be con-
nected from RBIAS to GND.
PFBOUT O 31 Power Feedback Output: Parallel caps, 10µ F and 0.1µF, s h oul d
be placed close to the PFBOUT. Connect this pin to PFBIN1 (pin
13), PFBIN2 (pin 27), PFBIN3 (pin35), PFBIN4 (pin 49). See
Section 5.4 for proper placement pin.
PFBIN1
PFBIN2
PFBIN3
PFBIN4
I 7
28
34
54
Power Feedback Input: These pins are fed with power from
PFBOUT pin. A small capacitor of 0.1
µF should be connected
close to each pin.
Note: Do not supply power to these pins other than from
PFBOUT.
RESERVED I/O 72, 73, 74,
75, 76
RESERVED: These pins must be left unconnected.
Signal Name Pin # Description
IOVDD1, IOVDD2, IOVDD3,
IOVDD4
11,51,65,78 I/O 3.3V Supply
IOGND1, IOGND2,
IOGND3, IOGND4
10,52,64,77 I/O Ground
COREGND1, COREGND2 6,55 Core Ground
CDGND1, CDGND2 25,37 CD Ground
ANA33VDD 30 Analog 3.3V Supply
ANAGND1, ANAGND2,
ANAGND3, ANAGND4
22,29,33,40 Analog Ground