TELEFUNKEN Semiconductors
U4311B
Low–Current Superhet Remote Control Receiver
Description
The U4311B is a monolithic Integrated Circuit in bipolar
technology for low-current UHF remote control super-
heterodyne receivers in amplitude- or frequency-
modulated mode. Typical applications are keyless car
lock-, alarm or telecontrol remote indication systems.
Especially for automotive applications it supports a
superhet design with about 1 mA total current consump-
tion, as required by the car manufacturers.
Features
D
Usable for amplitude- and frequency- modulated
transmission systems
D
Extremely low quiescent current approximately 1 mA
in the stand-by mode due to wake-up concept
D
Wide power supply voltage range 3 to 13 V
D
Sensitive IF-amplifier for 10.7 MHz operating
frequency
D
D
D
D
Logarithmic AM demodulator
FM demodulator
Monoflop exit to wake up a microcontroller
High performance operational amplifier to realize a
data recovering filter
depending hysteresis for data regeneration
D
Non-inverting clamping comparator with amplitude-
Block Diagram
Wake up out
V
S
10
V
Ref
= 2.4V
13
Bandgap
11
Internal
V
Ref
= 2.4 V
Monoflop
RF
Level
Wake up
Non – invert.
clamping
comparator
3
7
6
5 Data out
10.7 MHz
9
IF
amplifier
Quadrature
detector
–
4
8
log AM out
12
14
FM out
Data
filter
16
Operational
amplifier
+
1
95 9968
2
10.7 MHz
Figure 1. Block diagram
Rev. A1: 23.06.1995
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