Bit

Field Name

Description or Comment

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

0.7

4h’1

0.8

4h’2

0.9

4h’3

1

4h’4

1.1

4h’5

1.2 (default)

4h’6

1.3

4h’7

1.4

4h’8

1.5

4h’9

1.6

4h’A

1.7

4h’B

1.8

4h’C

1.9

4h’D

2

4h’E

2.1

4h’F

2.2

2:0

Unused

These bits are fixed to ‘0’. Reading these bits will result in a 3b’000. Any data

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

R9– PFM/PWM Force Register

Address 0x9

Type R/W

Reset Default 8h’00

Bit

Field Name

Description or Comment

7:6

PFM/PWM

Force

User Register

PFM Force (bit 7)

PWM Force (bit 6)

Automatic Transition

0

0

Automatic Transition

1

1

Forced PFM Mode

1

0

Forced PWM Mode

0

1

5:0

Unused

These bits are fixed to ‘0’. Reading these bits will result in a ‘000000’. Any data written into

these bits using the Register Write command is ignored.

R10-R14 – Unused Registers

Address 0xA, 0xB, 0xC, 0xD, 0xE

Type R/W

Reset Default 8h’00

Bit

Field Name

Description or Comment

7:0

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) frame.

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