ESMT

AD52070

Elite Semiconductor Microelectronics Technology Inc.

Publication Date: Oct. 2021

Revision: 1.1

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655ms/dB in AGC mode-Medium or 1311ms/dB in AGC mode-Slow, which is the

predefined release time. The AGC gain adjustment is applied with a ramp speed

selectable by the LIMRATE pin setting.

Figure.1 Waveform of output signal without clipping by rail

Figure.2 Waveform of output signal with clipping by rail

Attack Time

Release Time

Figure.3 Waveform of output signal with AGC ON

Table 2. AGC and Power limit Setting

LIMRATE Voltage

Mode

AGC attack rate

TFB attack

rate

AGC/TFB

release rate

GVDD

Fast (AGC)

0.32 ms/dB

164 ms/dB

328 ms/dB

2/3*GVDD

Medium (AGC)

2.56 ms/dB

326 ms/dB

655 ms/dB

1/3*GVDD

Slow (AGC)

5.12 ms/dB

655 ms/dB

1311 ms/dB

GND

PLIMIT

Disable

Disable

Disable

AGC function can not only automatically adjust system gain, but also further limit output

power of the amplifier without clipping. Figure 4 shows the output waveform with AGC

function. The limiter threshold set by the PLIMT pin voltage.

Attack Time

Release Time

Figure.4 Waveform of output signal with AGC