APPLICATION INFORMATION

High Gain

Built-In Gain

TLV1012

Airgap

Diaphragm

Electret

Connector

Backplate

A-Weighted Filter

-70

-60

-50

-40

-30

-20

-10

0

10

10

100

1000

10000

100000

Frequency – Hz

TLV1012

The TLV1012 provides outstanding gain compared to JFET amplifiers and still maintains the same ease of

implementation, with improved gain, linearity, and temperature stability. A high gain eliminates the need for extra

external components.

The TLV1012 is offered in the space-saving YDC package, which fits perfectly into the metal can of a

microphone. This allows the TLV1012 to be placed on the PCB inside the microphone.

The bottom side of the PCB usually shows a bull's-eye pattern, where the outer ring, which is shorted to the

resistor. This phantom biasing allows both supply voltage and output signal on one connection.

Figure 2. Built-In Gain

The human ear has a frequency range from 20 Hz to about 20 kHz. Within this range the sensitivity of the human

ear is not equal for each frequency. To approach the hearing response, weighting filters are introduced. One of

those filters is the A-weighted filter.

The A-weighted filter is usually used in signal-to-noise ratio measurements, where sound is compared to device

noise. It improves the correlation of the measured data to the signal-to-noise ratio perceived by the human ear.

Figure 3. A-Weighted Filter

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