micrf219a Micrel Semiconductor, micrf219a Datasheet
micrf219a
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micrf219a Summary of contents
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... General Description The MICRF219A is a 300MHz to 450MHz super- heterodyne, image-reject, RF receiver with automatic gain control, ASK/OOK demodulator, analog RSSI output, and integrated squelch features. It only requires a crystal and a minimum number of external components to implement. The MICRF219A is ideal for low-cost, low-power, RKE, TPMS, and remote actuation applications. ...
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... Data Output. Demodulated data output. A current limited CMOS output during normal operation, 25kΩ pull down is present when device is in shutdown. Tie this pin to VDD to ensure robust register programming. Use register bits D[4:3] to set demodulation 11 SEL1 bandwidth. July 2011 MICRF219AAYQS 2 RadioTech@micrel.com MICRF219A M9999-071811-A or (408) 944-0800 ...
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... Received Signal Strength Indicator. The voltage on this pin is an inversed amplified version of the voltage 14 RSSI on CAGC. Output is from a switched capacitor integrating op amp with 250Ω typical output impedance. 15 SCLK Programming clock input. Reference resonator connection to the Pierce oscillator. Internal capacitance of 7pF to GND during normal 16 RO2 operation. July 2011 3 RadioTech@micrel.com MICRF219A M9999-071811-A or (408) 944-0800 ...
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... 315MHz 433.92MHz RF −40dBm RF input level −100dBm RF input level f = 315MHz 433.92MHz RF RO1 when driven externally RO2 External input, AC couple to RO1 RO1 4 MICRF219A (2) ).................................... +3.0V to +3. ........................ –40°C to +105°C A Min. Typ. Max. 4.3 6.0 13 0.1 −112.5 −110 −112.5 −110 25 0.85 1.18 235 330 1.15 1.55 9.81713 13 ...
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... Device is ESD sensitive. Use appropriate ESD precautions. Exceeding the absolute maximum rating may damage the device. 4. Encoded bit rate is 1/(shortest pulse duration) that appears at MICRF219A DO pin ON/OFF keyed (OOK) signal, the signal level goes between a “mark” level (when the RF signal is ON) and a “space” level (when the RF signal is OFF). Sensitivity is defined as the input signal level when “ ...
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... PN9 SEQUENCE @ 1kbps 0.1 -116 -115 -114 -25 0 INPUT POWER (dBm) Sensitivity at 1% BER D[4: -98 -100 -102 -104 315MHz -106 -108 -110 -112 BIT RATE (kbps) RadioTech@micrel.com MICRF219A -40ºC 3.3 3.4 3.5 3.6 433.92MHz ` -113 -112 -111 -110 433.92MHz M9999-071811-A or (408) 944-0800 ...
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... XTAL -40 -50 -60 -70 -80 -90 -100 -110 -120 304 309 314 319 449 INPUT FREQUENCY (MHz) 7 Bandpass Filter Attenuation f = 9.81713MHz XTAL -10 -11 314.8 314.9 315.0 434.2 INPUT FREQUENCY (MHz) 324 M9999-071811-A RadioTech@micrel.com or (408) 944-0800 MICRF219A 315.1 315.2 ...
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... Micrel, Inc. Functional Diagram July 2011 Figure 1. Simplified Block Diagram 8 MICRF219A M9999-071811-A RadioTech@micrel.com or (408) 944-0800 ...
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... Micrel, Inc. Functional Description The simplified block diagram (Figure 1) illustrates the basic structure of the MICRF219A receiver made up of four sub-blocks: • UHF Down-Converter • ASK/OOK Demodulator • Reference and Control logic • Auto-poll circuitry Outside the device, the MICRF219A receiver requires ...
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... This voltage starts to drop when there is RF signal present. When the RF signal level is greater than −100dBm, the voltage is about 400mV. The value of the capacitor from CTH pin to GND is not critical to the sensitivity of MICRF219A, although it should be large enough to provide a stable slicing level ⎞ Operating ...
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... DECREASED in strength is much slower, since only 1.5μA is available to charge CAGC to increase the gain. When designing a transmitter that communicates with the MICRF219A, ensure that the power level remains constant throughout the transmit burst. The value of CAGC impacts the time to good data (TTGD), which is defined as the time when signal is first applied, to when the pulse width within 10% of the steady state value ...
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... The sleep time is programmable from 10ms to 1.28s polling state, every block in the MICRF219A is on, and the chip looks for signal with bit durations greater than a user- programmed value. ...
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... Micrel, Inc. Serial Interface Register Programming There are twenty register bits in MICRF219A. The functions are described in the following tables. D19 Always set this bit to 0 D18 Always set this bit D17 Squelch Enable Pin 0 0 Squelch Circuit Enabled 0 1 Squelch Circuit Disabled ...
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... Figure 7. Serial Interface Start Sequence sure the other bits (besides T1 < 0.1 us, Time from SCLK to convert DO to input pin T6 > 0.1 us, SCLK high time T7 > 0.1 us, SCLK low time T2, T3, T4, T5, T8, T9, T10 > 0.1 us Figure 8. Serial Interface Stop Sequence M9999-071811-A RadioTech@micrel.com or (408) 944-0800 MICRF219A D17) are ...
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... Serial Interface Register Loading Examples See Figures 9 to 11. (Channel 1 is the DO pin, and channel 2 is the SCLK pin). Figure 9. All Bits D19 through Figure 10. All Bits D19 through July 2011 Figure 11. D[19:18] = 11, D[17:0] = All 0s 15 RadioTech@micrel.com MICRF219A M9999-071811-A or (408) 944-0800 ...
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... D13 D12 causing damage. But applying put the part in an unknown test mode. If this accidently D6 D5 happens, cycle the power supply to restore the part to normal operation MICRF219A Figure 12. Auto-Poll Example + 0.3V without DD + 0.3V to SCLK can DD M9999-071811-A RadioTech@micrel.com or (408) 944-0800 ...
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... MICRF219A. The SHDN pin needs to have 50kΩ resistor to GND and a coupling capacitor to VDD as shown in the evaluation board schematic to ensure that the part starts up in shutdown mode first. Then the micro controller can bring the SHDN pin voltage down to turn the part on ...
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... IF bandwidth of MICRF219A. From this consideration, the tolerance should be ±50ppm on both the transmitter and the MICRF219A side. The ESR should be less than 300Ω, and the temperature range of the crystal should match the range required by the application ...
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... Micrel, Inc. PCB Recommended Layout Considerations July 2011 MICRF219A Evaluation Board Assembly MICRF219A Evaluation Board Top Layer MICRF219A Evaluation Board Bottom Layer 19 MICRF219A M9999-071811-A RadioTech@micrel.com or (408) 944-0800 ...
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... Micrel, Inc. MICRF219A Evaluation Board Schematic July 2011 20 RadioTech@micrel.com MICRF219A M9999-071811-A or (408) 944-0800 ...
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... Micrel, Inc. Bill of Materials − MICRF219A Evaluation Board: 433.92MHz Item Part Number C3 GQM1885C2A1R2C C4 GRM219R60J475K C5, C6 GRM188R71E104K C7 C9 GQM1885C2A1R5C C10, C11 GRM1885C1H100J C12 GRM188R61A105K J2 J3 571-41031480 L2 LQG18HN39NJ00 L3 LQG18HN33NJ00 R3 CRCW040250KFKEA R4 CRCW0402100KFKEA R5, R6 CRCW04020000Z R7, R8 ABLS-13.52313MHz-10J4Y Y2 DSX321GK-13.52313MHz U1 MICRF219AAYQS Notes: 1. Murata: www.murata.com. ...
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... Micrel, Inc. Bill of Materials − MICRF219A Evaluation Board: 315MHz Item Part Number C3 GQM1885C2A1R5C C4 GRM21BR60J475K C5, C6 GRM188R71E104K C7 C9 GQM1885C2A1R2C C10, C11 GRM1885C1H100J C12 GRM188R61A105K J2 J3 571-41031480 L2, L3 LQG18HN68NJ00 R3 CRCW040250KFKEA R4 CRCW0402100KFKEA R5, R6 CRCW04020000Z R7, R8 ABLS-9.81713MHz-10J4Y Y2 DSX321GK-9.81713MHz U1 MICRF219AAYQS Notes: 7. Murata: www.murata.com. ...
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... Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully July 2011 QSOP16 Package (AQS16) indemnify Micrel for any damages resulting from such use or sale. © 2011 Micrel, Incorporated. 23 http://www.micrel.com M9999-071811-A RadioTech@micrel.com or (408) 944-0800 MICRF219A nt ...