WM8955L

Product Preview

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Product Preview Rev 0.4 May2003

10

POWER CONSUMPTION

The power consumption of the WM8955L depends on the following factors.

•

Supplyvoltages: Reducing the supplyvoltages also reduces supplycurrents, and therefore results in significant power

savings.

•

Operating mode: Power consumption is lower in mono modes than in stereo, as one DAC is switched OFF. Unused

analogue outputs should be switched off.

Control Register

R24 R23 R38

Other settings

Tot. Power

Bit

V

I (mA)

V

I (mA)

V

I (mA)

V

I (mA)

(mW)

OFF

00 0 0 0 0 0 0 0 0 0

0

11

0

0 0

Clocks stopped

3.3

3.3

3.3

3.3

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Low-power standby(LPS)

10 1 0 0 0 0 0 0 0 0

0

11

0

0 0

3.3

3.3

3.3

3.3

using 500 KOhm VMID string

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Playback to Line-out

01 1 1 1 0 0 1 1 0 0

0

11

0

0 0

3.3

3.3

3.3

3.3

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Playback to Line-out

01 1 1 1 1 1 0 0 0 0

1

11

0

0 0

3.3

3.3

3.3

3.3

(64x oversampling mode)

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Playback

01 1 1 1 1 1 0 0 0 0

0

11

0

0 0

3.3

3.3

3.3

3.3

to 16 Ohm headphone

01

0

0 0

2.5

2.5

2.5

2.5

using caps on HPOUTL/R

00

0

0 0

1.8

1.5

1.5

1.8

Playback

01 1 1 1 1 1 0 0 0 1

0

11

0

0 0

R24, OUT3SW=00

3.3

3.3

3.3

3.3

to 16 Ohm headphone

01

0

0 0

2.5

2.5

2.5

2.5

capless mode using OUT3

00

0

0 0

1.8

1.5

1.5

1.8

Playback

01 1 1 1 0 0 1 1 0 0

0

11

0

0 0

R24, ROUT2INV=1

3.3

3.3

3.3

3.3

to 8 Ohm BTL speaker

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Headphone Amp

01 1 0 0 1 1 0 0 0 0

0

11

0

0 0

3.3

3.3

3.3

3.3

line-in to 16 Ohm h/phone

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Speaker Amp

01 1 0 0 0 0 1 1 0 0

0

11

0

0 0

R24, ROUT2INV=1

3.3

3.3

3.3

3.3

line-in to 8 Ohm speaker

01

0

0 0

2.5

2.5

2.5

2.5

00

0

0 0

1.8

1.5

1.5

1.8

Phone Call

01 1 00 110 01 1

0

11

1

0 0

3.3

3.3

3.3

3.3

diff. mono line-in to h/phone,

01

1

0 0

2.5

2.5

2.5

2.5

diff. mono line-out to TX

00

1

0 0

1.8

1.5

1.5

1.8

PLL only00 0 0 0 0 0 0 0 0 0

0

11

0

1 0

3.3

3.3

3.3

3.3

01

0

1 0

2.5

2.5

2.5

2.5

00

0

1 0

1.8

1.5

1.5

1.8

PLL and CLKOUT

00 0 0 0 0 0 0 0 0 0

0

11

0

1 1

3.3

3.3

3.3

3.3

01

0

1 1

2.5

2.5

2.5

2.5

00

0

1 1

1.8

1.5

1.5

1.8

Maximum Power

01 1 1 1 1 1 1 1 1 1

0

11

1

1 1

R24, ROUT2INV=1

3.3

3.3

3.3

3.3

everything ON

01

1

1 1

2.5

2.5

2.5

2.5

00

1

1 1

1.8

1.5

1.5

1.8

DBVDD

HPVDD

R43

R25

R26 (1Ah)

AVDD

DCVDD

Table 1 Supply Current Consumption (data to follow)

Notes:

1.

2.

All figures are quiescent, with no signal.

3.

The power dissipated in the headphone itself is not included in the above table.