MICRF104 Datasheet, PDF (1/10 Pages) Micrel Semiconductor – 1.8V, QwikRadio™ UHF ASK Transmitter

MICRF104
Micrel
MICRF104
1.8V, QwikRadio™ UHF ASK Transmitter
Final Information
General Description
The MICRF104 is a low voltage Transmitter IC for remote
wireless applications. The device employs Micrel’s latest
QwikRadio™ technology. This device is a true “data-in,
antenna-out” device. All antenna tuning is accomplished
automatically within the IC which eliminates manual tuning,
and reduces production costs. The result is a highly reliable
yet extremely low cost solution for high volume wireless
applications. The MICRF104 incorporates a DC/DC con-
verter to boost the input voltage up to 5V for the RF portion of
the IC. This feature enables the MICRF104 to operate off
supply voltages as low as 1.8V and transmit at power in
excess of –2dBm.
The MICRF104 uses a novel architecture where the external
loop antenna is tuned to the internal UHF synthesizer. This
transmitter is designed to comply worldwide UHF unlicensed
band intentional radiator regulations. The IC is compatible
with virtually all ASK/OOK (Amplitude Shift Keying/On-Off
Keyed) UHF receiver types from wide-band super-regenera-
tive radios to narrow-band, high performance super-hetero-
dyne receivers. The transmitter is designed to work with
transmitter data rates from 100 to 20k bits per second.
The automatic tuning in conjunction with the external resistor,
insures that the transmitter output power stays constant for
the life of the battery.
When coupled with Micrel’s family of QwikRadio™ receivers,
the MICRF104 provides the lowest cost and most reliable
remote actuator and RF link system available.
Features
• Complete UHF transmitter on a chip
• Frequency range 300MHz to 470MHz
• Data rates to 20kbps
• Automatic antenna alignment, no manual adjustment
• Low external part count
Applications
• Remote Keyless Entry Systems (RKE)
• Remote Fan/Light Control
• Garage Door Opener Transmitters
• Remote Sensor Data Links
Ordering Information
Part Number
MICRF104BM
Temperature Range
0°C to +85°C
Package
14-Pin SOIC
Typical Application
1.8V to 4V
Supply
10µF
RF Standby
L1
22µH
MICRF104
1 _VDDPWR
EN ¹⁴
2 _VSS
3
5V
4 _VSS
5 _REFOSC
6 _RFSTBY
7 _ANTM
VSS ¹³
12
SW
PC ¹¹
Power
Control
0.1µF 100pF 10µF
10
VDDRF
9
ASK
ANTP ⁸
DATA IN
LOOP
ANTENNA
(PCB TRACE)
Figure 1
QwikRadio is a trademark of Micrel, Inc. The QwikRadio ICs were developed under a partnership agreement with AIT of orlando, Florida
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
November 8, 2001
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MICRF104