AUTOMOTIVE ANTENNA AMPLIFIERS--MT1120 AUTOMOTIVE AM/FM ANTENNA AMPLIFIER SUBSYSTEM

The MT1120 is an advanced, lowpower,
highly integrated single-chip
amplifier IC specifically designed for
automotive AM/FM antenna systems
requiring low noise and very low
distortion. Additionally, the MT1120
integrates two true-RMS power
detectors and two uncommitted
op-amps in order to realize an AGC
function for AM and FM by simply
adding external PIN diodes. The
thresholds of the AM and FM AGC
function are variable and can be set
according to the application
requirements. The on-chip 2.55V
temperature compensated reference
generator and high output voltage
op-amp combine to form a low-cost,
reliable, automotive-capable power
supply which can be directly derived
from the car battery.
The MT1120 is capable of
amplifying signals with frequencies
in the 0.15 MHz to 30 MHz range for
AM and 76 MHz to 165 MHz range
for FM. External components
determine the gain of the AM and
FM amplifiers and can also be
modified to extend the operating
frequency of the MT1120.
The AM amplifier uses a highly
sophisticated design technology in
order to reach low noise, very low
distortion, high input impedance and
its capability to drive very low output
impedance. The FM amplifier is
matched to 50 ohms and is specially
designed to perform with very low
noise and distortion.
The small 28-pin QFN package
of the MT1120 and the requirement
for minimal external components
enables a compact, cost-effective
solution fulfilling automotive
requirements.
APPLICATIONS
In-glass antennas
Active roof antennas
Other active AM/FM antenna
systems
FEATURES
AM input frequency range
0.15 MHz to 30 MHz supports
AM, DRM and HD Radio
standards in the longwave,
midwave and shortwave band
FM input frequency range 76
MHz to 165 MHz supports
FM and HD Radio standards
in the FM and weather band
Fully integrated amplifiers for
AM and FM
Fully integrated RMS level
detectors and general
purpose op-amps (PIN-diode
drivers) for easy
implementation of AGC
functions for AM and FM
On-chip reference voltage
generator and high output
voltage op-amp builds a
reliable low-cost voltage
regulator function
Low noise
Low power consumption
Ultra low distortion
Very high AM input
impedance
Very small package
Highly sophisticated
temperature compensation
design technology to support
the extended automotive
ambient temperature range
from -40