Preamp Hybrid for Class D GS3001 - HYB DATA SHEET FEATURES DESCRIPTION • designed to drive class D integrated receivers The GS3001 incorporates Gennum’s GL504 preamp, all the required coupling and decoupling capacitors, and a midsupply referencing 48 kΩ resistor. All that is required further for a fully functioning hearing aid system is the addition of a microphone, receiver, volume control and an MPO adjusting potentiometer. • adjustable peak clipper • low current drain (150 µA typical) • 46 dB of adjustable gain • low external parts required (R , RMPO) VC The GS3001 can be mounted on the back of the hearing aid’s battery compartment. It has several access pads allowing for adjustment of the frequency characteristics. An additional ground pad (8a) is also included to aid in the manufacturability of the system. • low noise and distortion • mid supply referenced output STANDARD PACKAGING The GL504 chip is Gennum’s proprietary low current preamplifier designed to drive class D integrated receivers. This preamp has a built-in symmetrical peak clipping output limiter and up to 46 dB of adjustable gain. • Hybrid typical dimensions 0.140 in. x 0.240 in. x 0.110 in. (3.56 mm x 6.10 mm x 2.79 mm) The major advantage of the GL504 over other preamplifiers is the electronic MPO adjustment. Since conventional MPO is not possible for integrated receivers, it is provided in the preamp. The maximum output swing is easily set using an RMPO resistor. The receiver output level is thus limited, preventing it from exceeding the discomfort level. VMIC 6 3 10 VB RPULL C4 -B -A 2 47n CIN 7 C1 3µ3 C2 AIN RMIC 9 BOUT 8 5 47n R1 48k 1 GL504 3 4 2 1 MGND 4 C3 GS3001 HYBRID All resistors in ohms, all capacitors in farads unless otherwise stated. 47n 5 AOUT 6 BIN 8a 8 PGND 7 MPO BLOCK DIAGRAM Revision Date: May 1998 Document No. 520 - 46 - 08 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 CIN VALUE & UNITS Supply Voltage 3 V DC Power Dissipation 25 mW Operating Temperature -10 to + 40 °C Storage Temperature -20 to +70 °C AIN 2 VMIC 10 VB 3 9 BOUT MGND 4 8a PGND AOUT 5 8 PGND 1 BIN CAUTION 7 6 TOP VIEW MPO CLASS 1 ESD SENSITIVITY ELECTRICAL CHARACTERISTICS Conditions: Temperature 25 oC, Frequency = 1 kHz. PARAMETER SYMBOL CONDITION MIN TYP MAX UNITS 44.5 46.5 48.5 dB System Gain AV VIN = -80 dBV, Frequency = 5 kHz Amplifier Current IAMP VIN = 0, RMPO = 0 Ω 75 150 225 µA Maximum Output MPO VIN = -50 dBV, RMPO = 0 Ω -16 -14 -12 dBV MPO Range ∆MPO VIN = -50 dBV, RMPO = 10 kΩ 10 12 14 dB Input Referred Noise IRN NFB at 200 Hz to 10 kHz - 2 - µVRMS Distortion THD - <1.0 - % On Chip Pull-up Resistance RPULL - 48 - kΩ On Chip Microphone Resistor RMIC - 4 - kΩ Mic Decoupling Capacitor C1 -20% 3.3 +20% µF Input Coupling Capacitor C2 -10% 0.047 +10% µF Interstage Coupling Capacitor C3 -10% 0.047 +10% µF Output Coupling Capacitor C4 -10% 0.047 +10% µF Output Resistor R1 -5% 48 +5% kΩ Output Impedance (Pad 9) ROUT - 24 - kΩ (All conditions and parameters remain as shown in test circuit unless stated in condition column) 520 - 46 - 08 2 6 3 RMIC C1 3µ3 3k9 10 IAMP RPULL C2 5 9 8 47n VIN R1 48k 1 1kHz GL504 3 4 4 2 1 VOUT C4 -B -A 2 47n VB = 1.3 VDC 7 C3 GS3001 HYBRID 47n 5 8a 6 8 7 RMPO =10k RFA =100k All resistors in ohms, all capacitors in farads unless otherwise stated. Fig. 1 Production Test Circuit 1.3 VDC 3 6 7 C1 3µ3 2 5 47n 10 RPULL C2 MIC RMIC C4 -B -A CLASS D RECEIVER 9 8 47n 1µ R1 48k 1 GL504 3 4 4 2 1 C3 GS3001 HYBRID 47n 5 6 RFA =100k 8a 8 7 RMPO =10k All resistors in ohms, all capacitors in farads unless otherwise stated. Fig. 2 Typical Hearing Instrument Application 3 520 - 46 - 08 -10 -10 -15 RVC = 100k -15 R MPO R = 33k VC -45 RVC = 10k -55 -65 R -75 VC = 3.3k RMPO = 3.3k -25 RMPO = 10k -30 -35 -40 -85 -45 -95 -140 -120 -100 -80 -60 -40 -50 -100 -20 -90 -80 INPUT (dBV) -50 -40 -30 -20 10 0 C = 0.47µ 9 -2 8 -4 THD (%) RELATIVE OUTPUT (dB) -60 Fig. 4 I/O for Various RMPO Settings 2 -6 -8 C = 0.1µ -10 7 6 5 4 -12 3 -14 2 -16 NO CAP. -18 1 0 -90 -20 20 200 2k 20k -86 -82 -78 -74 -70 -66 -62 -58 INPUT (dBV) FREQUENCY (Hz) Fig. 6 Fig. 5 Frequency Response for Various C//C2 Values 0 -10 -10 -14 Distortion vs Input Level (RVC = 100 kΩ) No Load -18 -20 -30 OUTPUT (dBV) RELATIVE AMPLIFIER CURRENT (µA) -70 INPUT (dBV) Fig. 3 I/O for Various RVC Settings -40 -50 -60 -22 50kΩ Load -26 -30 -34 -38 -70 -42 -80 -46 -50 -90 0 5 10 15 20 25 30 1 10 100 1k 10k (kΩ) MPO R MPO (Ω) Fig. 7 Quiescent Current vs MPO Resistance Fig. 8 Output vs MPO Resistance R 520 - 46 - 08 = 0Ω -20 -35 OUTPUT (dBV) OUTPUT (dBV) -25 4 100k VOLUME CONTROL 2 MIC + 1 10 + 3 9 4 8a REC 5 7 + 8 6 BATTERY MPO TRIMMER Fig. 9 Typical Assembly Diagram TOP VIEW 2 10 1 3 9 3001 0.140 (3.56) XXXXXX 8a 4 5 7 6 8 0.240 (6.10 ) 0.125 (MAX) (3.18) BOTTOM VIEW C4 C1 Dimensioning units are inches. Dimensions shown in parenthesis are in millimetres, converted from inches and include minor round off errors. 1.0000 inches = 25.400mm Pad size 0.045 x 0.025 (1.14 x 0.64) Dimension tolerances ±0.005 (+0.13) unless otherwise stated. XXXXXX - work order number. Pad numbers and capacitor numbers for illustration only. C2 C3 Fig. 10 Hybrid Layout and Dimensions 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. REVISION NOTES: Updated to Data sheet 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 September 1991 Gennum Corporation. All rights reserved. 5 Printed in Canada. 520 - 46 - 08