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I2c bus interface and register settings, 1 i2c bus interface, 2 i2c bus tfa9812 device addresses – NXP Semiconductors TFA9812 User Manual

Page 27: Section 9, Tfa9812, C bus interface and register settings, Nxp semiconductors, C bus interface, C bus tfa9812 device addresses

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TFA9812_2

© NXP B.V. 2009. All rights reserved.

Preliminary data sheet

Rev. 02 — 22 January 2009

27 of 66

NXP Semiconductors

TFA9812

BTL stereo Class-D audio amplifier with I

2

S input

[1]

See,

Section 9.5.10

.

[2]

Window Protection is only checked at power-up.

9.

I

2

C bus interface and register settings

9.1 I

2

C bus interface

The TFA9812 supports the 400 kHz I

2

C bus microcontroller interface mode standard. This

can be used to control the TFA9812 and to exchange data with it when in I

2

C control

mode, see

Section 8.2.1

.

The TFA9812 can operate in I

2

C slave mode only as slave receiver or a slave transmitter.

The serial hardware interface involves the pins of the TFA9812 as described in

Table 22

.

Voltage values applied to the I

2

C bus device address pins are interpreted as described in

Table 23

.

9.2 I

2

C bus TFA9812 device addresses

Table 24

shows the register address options for the TFA9812 as part of the 8-bit byte that

contains the device address as well as the bit indicator read/write_not R/!W. The TFA9812
supports four different addresses, each of which can be configured using the pins
ADSEL1/PLIM1 and ADSEL2/PLIM2, see

Table 22

.

OFP

PLL frequency > 140 MHz

Floating

OFP

Floating

Restart (fault to operating
when
PLL frequency < 140 MHz)

IBP

BCK/WS is not 32

±

2,

48 2 or 64 2

Floating

-

Floating

Restart (fault to operating
when BCK/WS is 32

±

2,

48 2 or 64 2)

Table 21.

Overview protections

…continued

Protections

Symbol Conditions

DIAG
pin

I

2

C

flag

[1]

Output

Recovering

Table 22.

I

2

C pins in I

2

C control mode

Pin name

Description

SCL/SFOR

I

2

C bus clock input

SDA/MS

I

2

C bus data input and output

ADSEL2/PLIM2

I

2

C bus device address bit A2

ADSEL1/PLIM1

I

2

C bus device address bit A1

Table 23.

I

2

C pin voltages in I

2

C control mode

Logic value

Voltage A2/A1

0

< V

IL

1

> V

IH

Table 24.

I

2

C bus device address

(MSB)

Bit

(LSB)

1

1

0

1

0

A2

A1

R/!W