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U2740B Datasheet, PDF (1/10 Pages) TEMIC Semiconductors – UHF AM/FM Transmitter
UHF AM/FM Transmitter
U2740B
Description
The U2740B-B is an one-chip multi-purpose UHF
ASK/FSK transmitter IC designed for various applica-
tions within a wide frequency range. When a Chip-Select
(CS) signal is supplied, the IC starts operation (Power-up,
XTO, VCO, PD) and the VCO is then locked to
128 f(XTO). The locked status is indicated at the
Lock-Detect (LD) output.
The digital data is supplied to either an AM- or FM-input
pin, the output power being set via the AM-input pin. A
differential output enables simple applications with loop
antennas. An output driver (XTO_out) can be used for
clocking the microcontrolller.
Features
D One-chip solution with few external components
D Wide frequency range (200 to 500 MHz)
D Single voltage supply (2.2 to 5.5 V) with power-down
feature
D Adjustable output power with differential output for
loop antenna
D PLL lock-detect signal
D XTO output for µC clock
D ESD protection according to MIL–STD. 883
(except Pins 1, 2, 13 and 14)
D Low standby current <0.25 mA for VS = 3 V
D Single lithium-cell operation
Applications
D Keyless entry (automotive, domestic,...)
D Alarm systems
D Remote control
D Communication systems
Ordering Information
Extended Type Number
U2740B-BFP
Package
SO16
Remarks
System Block Diagram
1 Li cell
Antenna
U2740B
VCO
Encoder
Keys M44Cx9x
PLL
Power
ampl.
XTO
RF–Transmitter
Figure 1. System block diagram
13350
TELEFUNKEN Semiconductors
1 (10)
Rev. A3, 24-Feb-97
Preliminary Information