ATR4251_09 Datasheet, PDF (1/21 Pages) ATMEL Corporation – Low-noise, High-dynamic-range Antenna Amplifier IC

Features
• High Dynamic Range for AM and FM
• Integrated AGC for AM and FM
• High Intercept Point 3rd Order for FM
• FM Amplifier Adjustable to Various Cable Impedances
• High Intercept Point 2nd and 3rd Order for AM
• Low Noise Output Voltage
• Low Power Consumption
• Low Output Impedance AM
1. Description
The ATR4251 is an integrated low-noise AM/FM antenna amplifier with integrated
AGC in BiCMOS2S technology. The device is designed in particular for car applica-
tions, and is suitable for windshield and roof antennas.
Figure 1-1.
Block Diagram QFN24 Package
FM FM
FM AGC
VREF1 IN GAIN GND2 OUT IN
NC*
1
24
23
22
21
20
19
FM
amplifier
18
Paddle = GND
NC*
GND
2
AGC1
3
BAND
GAP
AGC
VS
17
AGCCONST
16
AGC2
4
VREF4
15
VREF2
5
AMIN
6
AM
7
8
AGC
(AM)
AMOUT1
14
GND1
13
9
10
11
12
NC* ^{CREG AGC AGC T NC*}
AMIN AM CONST
* Pin must not be connected to any other pin or supply chain except GND.
Low-noise,
High-dynamic-
range AM/FM
Antenna
Amplifier IC
ATR4251
4913J–AUDR–10/09