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MAX9812 Datasheet, PDF (1/11 Pages) Dallas Semiconductor – Tiny, Low-Cost, Single/Dual-Input, Fixed-Gain Microphone Amplifiers with Integrated Bias
19-2840; Rev 0; 4/03
Tiny, Low-Cost, Single/Dual-Input, Fixed-Gain
Microphone Amplifiers with Integrated Bias
General Description
The MAX9812/MAX9813 are single/dual-input, 20dB
fixed-gain microphone amplifiers. They offer tiny pack-
aging and a low-noise, integrated microphone bias,
making them ideal for portable audio applications such
as notebook computers, cell phones, and PDAs. These
amplifiers feature a 500kHz bandwidth, Rail-to-Rail®
outputs, an industry-leading 100dB power-supply rejec-
tion ratio, and a very low 0.015% THD+N. Power-saving
features include very low 230µA supply current and a
total shutdown mode that cuts the combined supply
and BIAS currents to only 100nA.
The MAX9812 is a single amplifier in a 6-pin SC70
package (2mm x 2.1mm) and the MAX9813 is a dual-
input amplifier available in an 8-pin SOT23 (3mm x
3mm) package. The MAX9813 has two inputs allowing
two microphones to be multiplexed to a single output.
The MAX9812/MAX9813 are offered in two grades. The
MAX9812L/MAX9813L are optimized for 3.3V supply
operation (2.7V to 3.6V). The MAX9812H/MAX9813H are
PC2001 compliant and are optimized for 5V operation
(4.5V to 5.5V). Both devices are specified over the -40°C
to +85°C extended operating temperature range.
Applications
Notebook Computers
PDAs
Smart Phones
Car Kit Adapters
Digital Cameras
Video Tape Recorders
Features
o PC2001 Compliant
o 100dB at 217Hz Power-Supply Rejection Ratio
o Very Low 230µA Quiescent Current
o Low 0.015% THD+N
o Available in Two Versions
MAX9812L/MAX9813L—2.7V to 3.6V
MAX9812H/MAX9813H—4.5V to 5.5V
o Internal Low-Noise Microphone Bias Supply
2.3V for MAX9812L/MAX9813L
4.0V for MAX9812H/MAX9813H
o 100nA Low-Power Shutdown Mode
o Rail-to-Rail Outputs
o 20dB Fixed Gain
o Available in Tiny 6-Pin SC70 (2mm x 2.1mm) and
8-Pin SOT23 (3mm x 3mm) Packages
o Extended Temperature Range -40°C to +85°C
Ordering Information
PART
PIN-
TEMP RANGE PACKAGE
VCC (V)
MAX9812LEXT-T -40°C to +85°C 6 SC70-6
2.7 to 3.6
MAX9812HEXT-T -40°C to +85°C 6 SC70-6
4.5 to 5.5
MAX9813LEKA-T -40°C to +85°C 8 SOT23-8 2.7 to 3.6
MAX9813HEKA-T -40°C to +85°C 8 SOT23-8 4.5 to 5.5
Pin Configurations, Selector Guide, and Typical Operating
Circuits appear at end of data sheet.
Rail-to-Rail is a trademark of Nippon Motorola Ltd.
Simplified Block Diagrams
VCC
VCC
BIAS
REFERENCE
2.3V (L VERSION)
4.0V (H VERSION)
SHDN
BIAS
REFERENCE
2.3V (L VERSION)
4.0V (H VERSION)
SHDN
IN1
IN
OUT
20dB
OUT
20dB
IN2
MAX9812
GND
IN1/IN2
MAX9813
GND
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.