DESCRIPTION

The LP508 is an 8 pin Class A amplifier utilizing Gennum's

proprietary low voltage bipolar JFET technology. It consists of

2 single ended, low noise inverting gain blocks. The first block

has a typical open loop gain of 50 dB, with the closed loop gain

set by the ratio of the feedback resistor to the the source

impedance. The second block has the output transistor bias

set by

R

E

and

V

Typically, the gain of the first block is set to 29 dB, with the

second block at 32 dB, giving a total gain of 61 dB.

BLOCK DIAGRAM

B IN

R

B OUT

V

E

B

GND

A OUT

A IN

V

MIC

1

2

4

3

8

7

5

18K

6

Document No. 500 - 71 - 9

Class A Amplifier with

2 Independent Gain Blocks

LP508 DATA SHEET

FEATURES

• 1

• 1.0 to 5 VDC operating range

• 61 dB typical gain (adjustable)

• 0.28 to 2.0 mA range of transducer current

• 1 % electrical distortion

• the first and second blocks can be DC coupled

• 4.0 k

• 100 Hz to 50 kHz frequency response

• volume control range >40 dB

STANDARD PACKAGING

• 8 pin MICROpac

• 8 pin PLID

®

• 8 pin SLT

• Chip (59 x 53 mils)

Au Bump

Revision Date: January 2001

GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 tel. +1 (905) 632-2996

Web Site: www.gennum.com

E-mail: hipinfo@gennum.com