 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
MICRF104 Datasheet(PDF) 6 Page - Micrel Semiconductor |
|
||||||||||||||||||||||||||||||
MICRF104 Datasheet(HTML) 6 Page - Micrel Semiconductor |
|
|
6 / 10 page 
MICRF104 Micrel MICRF104 6 November 8, 2001 Functional Description The block diagram illustrates the basic structure of the RF portion of the MICRF104. Identified in the figure are the principal functional blocks of the IC, namely the (1, 2, 3, 4, 5) UHF Synthesizer, (6a/b) Buffer, (7) Antenna tuner, (8) Power amplifier, (9) TX bias control, (10) Reference bias and (11) Process tuner. The UHF synthesizer generates the carrier frequency with quadrature outputs. The in-phase signal (I) is used to drive the PA and the quadrature signal (Q) is used to compare the antenna signal phase for antenna tuning purpose. Functional Diagram TX Bias Control Varactor Device Antenna Tuning Control Power Amp Buffer VSS ANTM ANTP ASK Buffer Prescaler Divide by 32 RF Transmitter REF.OSC PC VDDRF VDD (10) (5) (2) Reference Oscillator (1) VCO (4) (3) (9) (8) (7) (11) (6a) (6b) STBY Reference Bias Phase Detector 5V VSS VDDPWR EN Enable Thermal Shutdown Logic Driver Bandgap Reference DC/DC Converter Error Amplifier 1.2V SW Oscillator Figure 2. MICRF104 Block Diagram (RF Circuit) The Antenna tuner block senses the phase of the transmit signal at the antenna port and controls the varactor capacitor to tune the antenna. The Power control unit senses the antenna signal and con- trols the PA bias current to regulate the antenna signal to the transmit power. The Process tune circuit generates process independent bias currents for different blocks. A PCB antenna loop coupled with a resonator and a resistor divider network are all the components required to construct |
English ▼
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
