LMV1032-06_0511 Datasheet, PDF (1/12 Pages) National Semiconductor (TI) – Amplifiers for 3-Wire Analog Electret Microphones

November 2005
LMV1032-06/LMV1032-15/LMV1032-25
Amplifiers for 3-Wire Analog Electret Microphones
General Description
The LMV1032s are an audio amplifier series for small form
factor electret microphones. They are designed to replace
the JFET preamp currently being used. The LMV1032 series
is ideal for extended battery life applications, such as a
Bluetooth communication link. The addition of a third pin to
an electret microphones that incorporates an LMV1032 al-
lows for a dramatic reduction in supply current as compared
to the JFET equipped electret microphone. Microphone sup-
ply current is thus reduced to 60 µA, assuring longer battery
life. The LMV1032 series is guaranteed for supply voltages
from 1.7V to 5V, and has fixed voltage gains of 6 dB, 15 dB
and 25 dB.
The LMV1032 series offers low output impedance over the
voice bandwidth, excellent power supply rejection (PSRR),
and stability over temperature.
The devices are offered in space saving 4-bump ultra thin
micro SMD (TM) lead free packages and are thus ideally
suited for the form factor of miniature electret microphone
packages. These extremely miniature packages have the
Large Dome Bump (LDB) technology. This micro SMD tech-
nology is designed for microphone PCBs requiring 1 kg
adhesion criteria.
Features
(Typical LMV1032-15, 1.7V Supply; Unless Otherwise
Noted)
n Output voltage noise (A-weighted)
−89 dBV
n Low supply current
60 µA
n Supply voltage
1.7V to 5V
n PSRR
70 dB
n Signal to noise ratio
61 dB
n Input capacitance
n Input impedance
n Output impedance
2 pF
>100 MΩ
<200Ω
n Max input signal
n Temperature range
170 mV_PP
−40˚C to 85˚C
n Large Dome 4-Bump micro SMD package with improved
adhesion technology.
Applications
n Mobile communications - Bluetooth
n Automotive accessories
n Cellular phones
n PDAs
n Accessory microphone products
Block Diagram
Electret Microphone
20084201
© 2005 National Semiconductor Corporation DS200842
20084202
www.national.com