Usage Notes

• Microphone and TR amplifiers

Since these two amplifiers are designed for high gain (they support gains up to 40 dB), they cannot be used as buffer

amplifiers. Use at lower gains may result in loss of phase margin and oscillation. Therefore, the gain must be set to a

value of at least 6 dB.

• Handset amplifier output (pin 34)

A resistor (of at least 150

Ω) must be inserted in series if this output is connected directly to a dynamic speaker.

• BTL power amplifier

The phase compensation capacitor C4 is not required if the high-frequency noise reduction capacitor C1 is not used.

Also, the phase compensation capacitors C2, C3, and C4 should be placed as close as possible to the IC pins, with C2

located the closest.

• Inter-pin shorting

This IC may be damaged or destroyed if power is applied with any pins shorted together. Therefore, when mounting

this IC to a printed circuit board always check for pin shorting caused by stray solder or any other foreign material

before applying power.

• Load shorting

This IC may be damaged or destroyed if it is operated for extended periods with the load shorted. Do not allow the load

to be shorted.

• The slightest fluctuations in operating conditions may cause the ratings to be exceeded if this IC is operated in the

vicinity of the maximum ratings. Since this can lead to destruction of the device, applications must be designed with

adequate margins with respect to the power-supply voltage and other parameters so that the maximum ratings are never

exceeded.

No. 6075-7/17

LA8520M

Input