19-2515; Rev 0; 7/02
Electret Condenser Microphone Cartridge
Preamplifier
General Description
The MAX9810 microphone preamplifier is intended for
use inside electret condenser microphone (ECM) car-
tridges. Current solutions use a FET as an impedance
converter. FETs have limited gain, are susceptible to
noise and require additional components external to the
ECM cartridge for biasing and amplification. The
MAX9810 replaces the FET with a high-gain, high-noise
rejection, low-output-impedance amplifier. Designed to
be integrated inside the ECM cartridge, the MAX9810
offers a flat frequency response, tightly controlled gain,
increased sensitivity, and high-noise rejection greatly
simplifying system design. Target applications include
ECM cartridges in cell phones, PDAs, notebooks, and
other portable audio devices.
The MAX9810 operates from a single 2.3V to 5.5V sup-
ply and consumes only 670碌A(chǔ) of quiescent current. The
device features an internally generated 1.5V DC bias,
and is available in three internally fixed gain options
(24dB, 27dB, and 30dB). The MAX9810 is specified
over the extended temperature range (-40擄C to +85擄C)
and comes in a tiny 4-bump chip-scale package
(UCSP鈩? that is designed to fit inside the ECM cartridge.
Features
o
Replaces FET in Electret Condenser Microphone
o
2.3V to 5.5V Single-Supply Operation
o
Low-Impedance Output (<0.4鈩?
o
High PSRR: 82dB
o
Three High-Gain Options:
MAX9810A: 24dB
MAX9810B: 27dB
MAX9810C: 30dB
o
Internal Bias Voltage
o
Low Supply Current (670碌A(chǔ))
o
Rail-to-Rail
廬
Output
o
No Output Phase Reversal During Overload
Conditions
o
Available in a Tiny 4-Bump UCSP
MAX9810
Ordering Information
PART
MAX9810AEBS-T
MAX9810BEBS-T
MAX9810CEBS-T
TEMP RANGE
-40
o
C to +85
o
C
-40
o
C to +85
o
C
-40 C to +85 C
o
o
Applications
Electret Condenser Microphone Cartridges In:
Cell Phones
Notebooks
PDAs
Portable Audio
BUMP-
PACKAGE
4 UCSP-4
4 UCSP-4
4 UCSP-4
TOP
MARK
AFS
AFT
AFU
Selector Guide
PART
BUMP-PACKAGE
4 UCSP-4
4 UCSP-4
4 UCSP-4
GAIN
(dB)
24
27
30
Functional Diagram/
Typical Application Circuit
POWER
MAX9810AEBS-T
MAX9810BEBS-T
MAX9810CEBS-T
Pin Configuration
V
DD
ELECTRET
MIC
MAX9810
OUTPUT
TOP VIEW
(BUMP SIDE DOWN)
1
A
2
GND
GND
B
ECM CARTRIDGE
V
DD
OUT
MAX9810
IN
UCSP
GND
Rail-to-Rail is a registered trademark of Nippon Motorola Ltd.
USCP is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim鈥檚 website at www.maxim-ic.com.