High Power, Class B Output Stage GS551 DATA SHEET FEATURES CIRCUIT DESCRIPTION • adjustable gain to 48 dB The GS551 is a 10 pin, low voltage, class B amplifier which operates over a battery range of 1.1 VDC to 3 VDC. • capable of driving low impedance receiver • low component count, 3 small capacitors and 1 resistor • gain trim can be used as vol. control for reduced noise • minimal start-up transient • no gain expansion STANDARD PACKAGING • 10 pin MICROpac • 10 pin PLID® The GS551 consists of three gain blocks. The first block is an inverting amplifier with the gain set by two external resistors. The gain trim feature can be used as a volume control in hearing aid applications. The second block is an inverting unity gain amplifier which serves as a phase splitter. The outputs from the first and second blocks drive the differential input of the third block. The third block has a fixed AC gain of 28 dB when driving a receiver. The amplifier has internal compensation eliminating the need for a capacitor across the receiver. Two ground pins are available for “Star” grounding to reduce any second order harmonic distortion introduced by ground line resistance. • 10 pin SLT • Chip (68 x 60 mils) VB 6 10 A IN 5 -A C OUT 2 -B C A OUT 1 REFERENCE VOLTAGE C OUT 1 4 2 GND 1 9 GND 2 7 8 3 VREF DEC 2 DEC 1 U.S. Patent No. 4,719,430 Other Patents Pending BLOCK DIAGRAM Revision Date: January 2001 Document No. 510 - 31 - 04 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: [email protected] PIN CONNECTION ABSOLUTE MAXIMUM RATINGS PARAMETER VALUE/UNITS VB 5 VDC A IN Operating Temperature -10 to +40 °C A OUT VREF Storage Temperature -20 to +70 °C DEC 1 DEC 2 GND 1 GND 2 Supply Voltage CAUTION CLASS 1 ESD SENSITIVITY 5 C OUT 1 6 1 10 COUT 2 ELECTRICAL CHARACTERISTICS Conditions: Frequency = 1 kHz, Temperature = 25°C, Supply Voltage VB = 1.3 VDC PARAMETER SYMBOL CONDITIONS TYP MAX UNITS 46 48 50 dB Gain AV Amplifier Current IAMP 120 220 335 µA Transducer Current I TRANS 120 250 390 µA Input Referred Noise IRN NFB 0.2 to 10 kHz at 12 dB/Oct - 1.3 2.5 µV THD VO=0.707 VRMS - 0.25 1.3 % VO=1.3 VRMS - 0.3 1.5 % Total Harmonic Distortion VO=0.707 VRMS MIN Stable with RB to RSTAB RB=22Ω - - 22 Ω Maximum Output Current IOUT V P8=0 - >35 - mA All parameters remain as shown in Test Circuit unless otherwise stated in "Conditions" column VB = 1.3VDC RB = 4.7 6 IOUT 10 CS RS 5 -A 0.1 10k C RL = 400 100k 1 kHz 1 REFERENCE VOLTAGE 4 2 9 7 8 3 0.047 0.047 All resistors in ohms,all capacitors in farads unless otherwise stated Fig. 1 Test Circuit 510 - 31 - 04 VO -B 2 6 4 7 Base Current Compensation 2 5 6 1 10 8 2 3 9 Fig. 2 GS551 Functional Schematic 1.3 VDC 4 3 2 RS 3.9k 6 REGULATOR 4.7 0.1 10 + 0.1 10k 5 _ 30k 230 -A -B C RVC 100k 1 REFERENCE VOLTAGE 1.0 RGT 50k 4 LC506 1 GS551 2 5 CI2960 9 8 3 7 0.047 0.047 All resistors in ohms,all capacitors in farads unless otherwise stated Fig. 3 Application Circuit 3 510 - 31 - 04 4 10 2 0 RVC=100k -2 RVC=47k RELATIVE OUTPUT (dB) OUTPUT (dBV) -20 RVC=22k -30 RVC=10k -40 -50 RVC=3.3k -60 -70 -80 -90 -130 -120 -110 -100 -90 CS=0.22 µF 0 -10 CS=0.1 µF -4 CS=0.047 µF -6 -8 CS=0.033µF -10 -12 -14 -16 -18 -20 -80 -70 -60 -50 -40 -30 20 -20 -10 200 INPUT (dBV) 14 10 13 5 12 0 11 -5 10 RELATIVE GAIN (dB) POWER OUTPUT (mW) 20k Fig. 5 Closed Loop Frequency Response at Various CS Values (RS=3.92k) Fig. 4 I/O Characteristics at Various Gain Settings (RS=3.92k) 9 8 7 6 5 4 3 -10 -15 -20 -25 -30 -35 2 -40 1 -45 0 0 100 200 300 400 500 600 700 800 -50 900 1000 .8 .9 LOAD RESISTANCE (Ω) 1.1 1.2 1.3 1.4 Fig. 7 Gain vs Supply Voltage 0.10 50 RELATIVE AMPLIFIER CURRENT (µA) 0.08 0.06 0.04 0.02 0 -0.02 -0.04 -0.06 -0.08 -0.10 -20 1 SUPPLY VOLTAGE (VDC) Fig. 6 Power Outout vs Load Resistance at 7% Distortion, RB=0Ω, VB=1.35V RELATIVE GAIN (dB) 2k FREQUENCY (Hz) -10 0 10 20 30 40 50 40 30 20 10 0 -10 -20 -30 -40 -50 -60 -70 -20 TEMPERATURE (°C) -10 0 10 20 30 40 50 TEMPERATURE (°C) Fig. 8 Gain vs Temperature Fig. 9 Amplifier Current vs Temperature GENNUM CORPORATION DOCUMENT IDENTIFICATION: DATA SHEET The product is in production. Gennum reserves the right to make changes at any time to improve reliability, function or design, in order to provide the best product possible. MAILING ADDRESS: P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 Tel. +1 (905) 632-2996 Fax +1 (905) 632-2814 SHIPPING ADDRESS: 970 Fraser Drive, Burlington, Ontario, Canada L7L 5P5 REVISION NOTES: GENNUM JAPAN CORPORATION Changes to standard packaging information. C-101, Miyamae Village, 2-10-42 Miyamae, Suginami-ku, Tokyo 168-0081, Japan Tel. +81 (3) 3334-7700 Fax: +81 (3) 3247-8839 Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. © Copyright August 1988 Gennum Corporation. All rights reserved. 510 - 31 - 04 4 Printed in Canada.