R5-R6 - Unused Registers

Address 0x5, 0x6

Type R/W

Reset Default 8h’00

Bit

Field Name

Description or Comment

7:00

Unused

Write transactions to this register are ignored. Read transactions will

return a “No Response Frame.” A no response frame contains all

zeros (see PWI 1.0 specification).

R7 – VO2 Voltage Register (I/O Voltage)

Address 0x7

Type R/W

Reset Default 8h’78

Bit

Field Name

Description or Comment

7

Sign

This bit is fixed to ‘0’. Reading this bit will result in a ‘0’. Any data written into

this bit position using the Register Write command is ignored.

6:3

Voltage

Fixed voltage value. A code of all ones indicates maximum voltage while a code

of all zero indicates minimum voltage. Default value is in bold.

Voltage Data Code [6:3]

Voltage Value (volts)

4h’0

1.5

4h’1

1.5

4h’2

1.5

4h’3

1.5

4h’4

1.6

4h’5

1.7

4h’6

1.8

4h’7

1.9

4h’8

2

4h’9

2.1

4h’A

2.2

4h’B

2.3

4h’C

2.5

4h’D

2.8

4h’E

3

4h’F

3.3 (default)

2:0

Unused

These bits are fixed to ‘0’. Reading these bits will result in a ‘000’. Any data

written into these bits using the Register Write command is ignored.

R8 – VO1 Voltage Register (PLL/Fixed Voltage)

Address 0x8

Type R/W

Reset Default 8h’28

Bit

Field Name

Description or Comment

7

Sign

This bit is fixed to ‘0’. Reading this bit will result in a ’0’. Any data written into

this bit position using the Register Write command is ignored.

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