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FIGURE 4. Example Write Sequence

TABLE 2. Device Address

B7

B6

B5

B4

B3

B2

B1

B0 R/W

Chip Address

1

1

1

0

1

1

0

0

TABLE 3. Mode Control Registers

Register Name

B7

B6

B5

B4

B3

B2

B1

B0

Mode Control

VOL4

VOL3

VOL2

VOL1

VOL0

0

ENABLE_A

ENABLE_B

GENERAL AMPLIFIER FUNCTION

The LM48823 is a ceramic speaker driver that utilizes National’s inverting charge pump technology to deliver over 15V

2.2µF ceramic speaker while operating from a single 4.2V supply. The LM48823 features a unique input stage that converts two

single-ended audio signals into a mono BTL output. This stereo to mono conversion is useful in applications where a stereo audio

source is driving a single ceramic speaker, such as a ringer on a cellular phone. Connect INA and INB as shown in Figure 5 for

the stereo-to-mono conversion. When the LM48823 is used with a single-ended mono audio source, connect both INA and INB to

the audio source as shown in Figure 6.

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FIGURE 5. Stereo to Mono Conversion Connection Example

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FIGURE 6. Mono Audio Source Connection Example

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