Switch Current Limit vs. V

IN

Efficiency vs. Load (Switcher)

20154518

20154519

Switching Waveforms

PWM

Switching Waveforms

PFM

20154520

20154521

LP5550 PWI Register Map

The PWI standard supports sixteen 8-bit registers on the PWI slave. The table below summarizes these registers and shows

default register bit values after reset. The following sub-sections provide additional detail on the use of each individual register.

Summary

Register

Address

Register

Name

Register Usage

Type

Reset Default Value

7654

3

2

1

0

0x0

R0

Core voltage

R/W

0111

1

1

1

1

0x1

R1

Unused

R/W

----

-

-

-

-

0x2

R2

Memory retention voltage

R/W

0110

0

-

-

-

0x3

R3

Status register

R/O

0000

1

1

1

1

0x4

R4

PWI version number

R/O

0000

0

0

0

1

0x5

R5

Unused

R/W

----

-

-

-

-

0x6

R6

Unused

R/W

----

-

-

-

-

0x7

R7

LDO2 voltage

R/W

0111

1

-

-

-

0x8

R8

LDO1 voltage

R/W

0010

1

-

-

-

0x9

R9

PFM/PWM force

R/W

0

0

-

-

-

-

-

-

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