器件名称: U2538B
功能描述: IR RECEIVER FOR DATA COMMUNICATION
文件大小: 173.57KB 共9页
简 介:Features
Few External Components Low Power Consumption Microcomputer Compatible Insensitive to Ambient Light and Other Continuous Interferences
Applications
Keyless Entry Systems Remote Control Wireless Data Transfer up to 4 kbit/s
Description
The IC U2538B is a complete IR receiver for data communication. The useful input signals are separated by a special input circuit and amplified by a gain-controlled amplifier. The bandpass filter suppresses the off-band signals. The signal detector, consisting of a demodulator, an integrator and a Schmitt trigger, forms the input signal to an output pulse that can be interfaced to a microcomputer. The AGC and the ATC circuit control the receiver's sensitivity, making it insensitive to ambient light sources. Figure 1. Block Diagram with Typical Circuit
VS
IR Receiver for Data Communication U2538B
U2538B
Input Amplifier and filter Detector mC
AGC/ATC
Modulated IR signal carrier frequency 20 to 60 kHz minimum 6 pulses/burst
Rev. 4717A–IRRC–05/03
1
Block Diagram
VS RF0 RF VS
BIAS IN BPF
+ -
Comp 1
100 kW
OUT & dt
Vth + -
Comp 2 INT ST
TIA
CGA
AGC
ATC
DEM
AGND
CAGC
CAGC
DGND
TIA CGA BPF AGC
Transimpedance amplifier Controlled gain amplifier Bandpass filter Automatic gain control
ATC DEM INT ST
Automatic threshold control Demodulator Integrator Schmitt trigger
2
U2538B
4717A–IRRC–05/03
U2538B
Pin Configuration
Figure 2. Pinning SO8
NC 8 RF 7 AGND 6 IN 5
U2538B
1 VS
2 CAGC
3 OUT
4 DGND
Pin Descrip……
