The LM4867’s pin configuration simplifies the process of

upgrading systems that use the LM4863. Except for its four

MUX function pins, the LM4867’s pin configuration matches

the LM4863’s pin configuration. If the LM4867’s MUX func-

tionality is not needed when replacing an LM4863, connect

the MUX CTRL pin to either V

correct amplifier operation, unused MUX inputs must be

tied to GND. As shown in Table 1, grounding the MUX CTRL

pin selects stereo input 1 (−IN A1 and −IN B1), whereas

applying V

(−IN A2 and −IN B2).

The LM4867’s unique headphone sense circuit requires a

dual switch headphone jack. Replace the four-terminal head-

phone jack used with the LM4863 and LM4873 with the

five-terminal headphone jack, such as the Switchcraft

35RAPC4BH3, shown in Figure 4. Connect the +OUT A

(Amp2A) pin to the five-terminal headphone jack’s sleeve

pin.

DS200013-57

FIGURE 3. Single-ended output signal (Trace B) is

devoid of transients. The SHUTDOWN pin is driven by

a shutdown signal (Trace A). The inverting output

(Trace C) and the V

across a 32

Ω BTL load.

DS200013-31

FIGURE 4. Typical Audio Amplifier Application Circuit

(Pin out shown for the 24-pin Exposed-DAP LLP package. Numbers in ( ) are for the 20-pin MTE and MT packages.)

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