|
|
TH72012
Transmitter - 433MHz, ASK (SOIC8)
 Download TH72012 Datasheet (PDF)
Subscribe To Updates
TH72012 General Description
The TH72012 ASK transmitter IC is designed for applications in the European 433 MHz industrial-scientific-medical (ISM) band, according to the EN 300 220 telecommunications standard; but it can also be used in other counties with similar standards, e.g. FCC part 15.231.
The transmitter's carrier frequency fc is determined by the frequency of the reference crystal fref. The integrated PLL synthesizer ensures that carrier frequencies, ranging from 380 MHz to 450 MHz, can be achieved. This is done by using a crystal with a reference frequency according to: fref = fc/N, where N = 32 is the PLL feedback divider ratio.
TH72012 Features and Benefits
- Fully integrated PLL-stabilized VCO
- Frequency range from 380 MHz to 450 MHz
- Single-ended RF output
- ASK achieved by on/off keying of internal power amplifier up to 40 kbit/s
- Wide power supply range from 1.95 V to 5.5 V
- Operating temperature range -40°C to +125°C
- Very low standby current
- On-chip low voltage detector
- High over-all frequency accuracy
- Adjustable output power range from -11 dBm to +10 dBm
- Adjustable current consumption from 3.4 mA to 10.6 mA
- Conforms to EN 300 220 and similar standards
- 8-pin Small Outline Integrated Circuit (SOIC)
TH72012 Applications
| Application Note |
File Type |
Size |
Revision |
Date |
Action |
| PA Output Matching |
PDF |
114.5 KB |
001 |
4/10/2006 |
|
TH72012 Environmental Information
This text will be replaced
TH72012 Frequently asked Questions
about TH72012.2 0306 and TH72012.2 0347
Answer
We use TH72012 for 434MHz ASK Transmitter. at first, we
bought hundreds chips marked:"TH72012.2 0306", the
performance were OK.
After, we bought another hundreds chips again,
marked:"TH72012.2 0347", this time, we found many chips
transmitting frequency are at 404MHz, but if i touch
the crystal by finger,frequency will change to 434MHz.
Can you help me to solve this peoblem?
TH72012: need more power
Question
I'm trying to use a TH72012 to improve trasmission power in an application where I send data with a bitrate of 3Kbit/s, with an on/off modulation on 433.92MHz. I'm using suggested circuit in datasheet, but I don't know how to match the antenna. I would like to try a stylus 170mm long (lambda/4) or, better, a closed loop 50mm long printed in a PCB. How can I modify the circuit to have more power?
NOTE: using as transmitter a RF transistor (BFR93A) with a SAW resonator and a 50mm long closed loop as antenna, now I can measure, with a spectrum analyzer placed to 10mt, about 10dB more than with the circuit using TH72012 and a stylus 170mm long. WHAT'S WRONG???
EVB72032 Antenna Gain
Answer
The loop dimensions are already given in the EVB description: http://www.melexis.com/prodfiles/evb72032_rev006.pdf . Nevertheless there are some postings and links regarding this issue: "TH72012: need more power" & "TH72002".
FM with all TH71xxx /TH72xxx
Question
I'm looking for a low-cost IC for a simply analog signal transmission (with FM) on the european ISM-band.
Is it possible to solve this problem with each of the transmitter chips of the 2end /3erd generation?
Which one can I take for this project (maybe TH71071 or TH72012)?
Buy TH72012
|
|