19-2840; Rev 0; 4/03
Tiny, Low-Cost, Single/Dual-Input, Fixed-Gain
Microphone Amplifiers with Integrated Bias
General Description
Features
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.
ꢀ PC2001 Compliant
ꢀ 100dB at 217Hz Power-Supply Rejection Ratio
ꢀ Very Low 230µA Quiescent Current
ꢀ Low 0.015% THD+N
ꢀ Available in Two Versions
MAX9812L/MAX9813L—2.7V to 3.6V
MAX9812H/MAX9813H—4.5V to 5.5V
ꢀ Internal Low-Noise Microphone Bias Supply
2.3V for MAX9812L/MAX9813L
4.0V for MAX9812H/MAX9813H
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.
ꢀ 100nA Low-Power Shutdown Mode
ꢀ Rail-to-Rail Outputs
ꢀ 20dB Fixed Gain
ꢀ Available in Tiny 6-Pin SC70 (2mm x 2.1mm) and
8-Pin SOT23 (3mm x 3mm) Packages
ꢀ Extended Temperature Range -40°C to +85°C
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.
Ordering Information
PIN-
PART
TEMP RANGE PACKAGE
V
(V)
CC
Applications
MAX9812LEXT-T -40 C to +85 C 6 SC70-6
MAX9812HEXT-T -40 C to +85 C 6 SC70-6
MAX9813LEKA-T -40 C to +85 C 8 SOT23-8
MAX9813HEKA-T -40 C to +85 C 8 SOT23-8
2.7 to 3.6
4.5 to 5.5
2.7 to 3.6
4.5 to 5.5
Notebook Computers
PDAs
Smart Phones
Pin Configurations, Selector Guide, and Typical Operating
Circuits appear at end of data sheet.
Rail-to-Rail is a trademark of Nippon Motorola Ltd.
Car Kit Adapters
Digital Cameras
Video Tape Recorders
Simplified Block Diagrams
V
V
CC
CC
SHDN
OUT
SHDN
OUT
REFERENCE
2.3V (L VERSION)
4.0V (H VERSION)
REFERENCE
2.3V (L VERSION)
4.0V (H VERSION)
BIAS
BIAS
IN1
IN2
IN
20dB
20dB
IN1/IN2
MAX9812
MAX9813
GND
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.