si4021 Silicon Laboratories, si4021 Datasheet
si4021
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si4021 Summary of contents
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... Si4020 by offering a higher output power and an improved phase noise characteristic. The Si4021 shares the same pinout and control command set as the Si4020. The Si4021 offers all of the frequencies as the Si4020, with the exception of the 315 MHz band. ...
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... DETAILED DESCRIPTION The Si4021 FSK transmitter is designed to cover the unlicensed frequency bands at 433, 868, and 915 MHz. The device facilitates compliance with FCC and ETSI requirements. PLL The programmable PLL synthesizer determines the operating frequency, while preserving accuracy based on the on-chip crystal-controlled reference oscillator. The PLL’ ...
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PACKAGE PIN DEFINITIONS, MICROCONTROLLER MODE Pin type key: D=digital, A=analog, S=supply, I=input, O=output, IO=input/output Microcontroller Mode Pin Assignment Pin Name Type 1 SDI DI 2 SCK DI 3 nSEL DI 4 PB1 DI 5 PB2 DI 6 PB3 DI 7 ...
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Typical Application, Microcontroller Mode VDD GP3 GP4 GP6 To other GP7 MICRO circuits GP2 GP8 CONTROLLER GP1 GP9 GP0 GP5 CLKin (EC osc. mode) GND OPTIONAL 100p 10p GND OPTIONAL SDI 1 2 SCK 3 nSEL ...
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PACKAGE PIN DEFINITIONS, EEPROM MODE Pin type key: D=digital, A=analog, S=supply, I=input, O=output, IO=input/output EEPROM Mode Pin Assignment Pin Name Type 1 SDI DI 2 SCK DO 3 nSEL DO 4 PB1 DI 5 PB2 DI 6 PB3 DI 7 ...
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Typical Application, EEPROM Mode VDD 100p GND OPTIONAL GND C3 10p 1 8 nCS EEPROM 3 6 nWP 25A A 080 GND SDI SCK 3 ...
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GENERAL DEVICE SPECIFICATIONS All voltages are referenced the potential on the ground reference pin VSS. ss Absolute Maximum Ratings (non-operating) Symbol Parameter V Positive supply voltage dd V Voltage on any pin except open collector outputs in ...
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AC Characteristics Symbol Parameter f PLL reference frequency ref f Transmitter frequency o t PLL lock time lock t PLL startup time sp Open collector output current (Note I OUT 3) Available output power P maxL (433 MHz band) Available ...
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... Using anything but a 10 MHz crystal is allowed but not recommended because all crystal-referred timing and frequency parameters will change accordingly. Note 3: Adjustable in 8 steps. Note 4: Optimal antenna admittance/impedance for the Si4021: 434 MHz 868 MHz 915 MHz Note 5: With selective resonant antennas (see: Application Notes available from http://www.silabs.com/integration). ...
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TYPICAL PERFORMANCE DATA Phase noise measurements in the 868 MHz ISM band 50% Charge pump current setting (Ref. level: -60 dBc/Hz, 10 dB/div) 11:52:47 May 5, 2005 Phase Noise Carrier Power -11.11 dBm Atten 0.00 dB Ref -60.00dBc/Hz 10.00 dB/ ...
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Modulated RF Spectrum At 433 MHz with 180 kHz Deviation at 64 kbps 17:11:41 Dec 7, 2005 Ref 10 dBm Atten 20 dB #Samp Log 10 dB/ VAvg Center 434 MHz #Res BW 1 ...
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CONTROL INTERFACE Commands to the transmitters are sent serially. Data bits on pin SDI are shifted into the device upon the rising edge of the clock on pin SCK whenever the chip select pin nSEL is low. When the nSEL ...
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Control Commands Control Command 1 Configuration Setting Command 2 Power Management Command 3 Frequency Setting Command 4 Data Rate Command 5 Power Setting Command 6 Low Battery Detector Command 7 Sleep Command 8 Push-Button Command 9 Wake-Up Timer Command 10 ...
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Power Management Command bit Bits 5-0, enable the corresponding block of the transmitters, i.e. the crystal oscillator is enabled by the ex bit, the synthesizer by es, the ...
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Frequency Setting Command bit f11 f10 The 12-bit parameter of the Frequency Setting Command <f11 : f0> has the value F. The value F should be in the range ...
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Low Battery Detector Command bit Bit 7 <dwc> Disables the Wake-up timer periodical (every 30 second) calibration if this bit is set. Bit 5 <ebs> Enables the TX ...
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Push-Button Command bit the corresponding bit was set (b1-b4) the event remains active while the button is pressed. In EEPROM mode, the chip is continuously performing the ...
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Simultaneously Pressed Push-Button Detect by Microcontroller Microcontroller mode Vdd POR (internal) Push button input 1 Push button input 2 nIRQ POR PB1 PB_nIRQdly* SPI Status rd Status rd Simplified Block Diagram of Push-Button 1–4 Inputs VDD WEAK PULL-UP ENABLE/DISABLE Push-button1,2,3 ...
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Wake-Up Timer Command bit The wake-up time period can be calculated as [ms wake-up where M is defined by the ...
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Data Transmit Sequence Through the FSK Pin nSEL SCK instruction SDI Xtal osc staus Internal ...
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Status Register Read Command bit With this command possible to read the chip’s status register through the nIRQ pin. This command clears the last serviced interrupt ...
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EEPROM MODE In this mode, the transmitters can operate with a standard at least 1 kbyte serial EEPROM with an SPI interface, and no microcontroller is necessary. The following events cause wake-up of the device: Event Number ...
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Push-button 1: 00000080 00000090 000000A0 000000B0 000000C0 000000D0 000000E0 000000F0 00 00 ...
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... CRYSTAL SELECTION GUIDELINES The crystal oscillator of the Si4021 requires a 10 MHz parallel mode crystal. The circuit contains an integrated load capacitor in order to minimize the external component count. The internal load capacitance value is programmable from 8 0.5 pF steps. With appropriate PCB layout, the total load capacitance value can variety of crystal types can be used. ...
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RESET MODES The chip will enter into reset mode if any of the following conditions are met: • Power-on reset: During a power up sequence until the V • Power glitch reset: Transients present on the V • Software reset: ...
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Sensitive Reset Enabled, Ripple Reset threshold voltage (600mV) 1.6V H nRes output L Sensitive reset disabled Reset threshold voltage (600mV) 250mV H nRes output L Software reset Software reset can be issued ...
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SIMPLIFIED INTERNAL CONTROL AND TIMING The internal controller uses the clock generated by the crystal oscillator to sequentially process the various events and to de-bounce the push-button (PB) inputs. If the oscillator is not running, internal logic automatically turns it ...
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... MATCHING NETWORK FOR A 50 OHM SINGLE ENDED OUTPUT Matching Network Schematic Si4021 L1 [nH] L2 [nH] 433 MHz 16 47 868 MHz 5.1 24 915 MHz 4.3 24 Note thick board Note 2: 1.5 mm thick board Note 3: C4 must be connected parallel to the supply decoupling capacitors (10nF + 2.2µF recommended) as close as possible to the VDD ...
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EXAMPLE APPLICATIONS: DATA PACKET TRANSMISSION Data packet structure An example data packet structure using the IA422x – IA4320 pair for data transmission. This packet structure is an example of how to use the high efficiency FIFO mode at the receiver ...
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EXAMPLE APPLICATIONS For Microcontroller Mode Schematic PCB Layout of Keyboard Transmitter Demo Circuit Using Microcontroller Mode (operating in the 915 MHz band) Top Layer IA4221 IA4221 Bottom Layer 30 ...
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For EEPROM Mode Schematic PCB Layout of Push-Button Transmitter Demo Circuit Using EEPROM Mode (operating in the 434 MHz band) Top Layer IA4221 Bottom Layer 31 ...
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PACKAGE INFORMATION 16-pin TSSOP Symbol Min 4, ...
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... RELATED PRODUCTS AND DOCUMENTS Si4021 Universal ISM Band FSK Transmitter DESCRIPTION Si4021 16-pin TSSOP die Demo Boards and Development Kits DESCRIPTION Development Kit Remote Temp. Monitoring Station Related Resources DESCRIPTION Antenna Selection Guide Antenna Development Guide IA4320 Universal ISM Band FSK Receiver Note: Volume orders must include chip revision to be accepted ...