SX1223I073TRT Semtech, SX1223I073TRT Datasheet
SX1223I073TRT
Specifications of SX1223I073TRT
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SX1223I073TRT Summary of contents
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... RF On-chip frequency synthesizer Continuous phase 2-level FSK modulation Very small RoHS green package (TQFN24, 4mm x 4mm) ORDERING INFORMATION Part number SX1223I073TRT (1) TR refers to tape & reel. T refers to Lead Free package. This device is WEEE and RoHS compliant. SX1223 Temperature Package range (1) -40 ° ...
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... Optional and Test Parameters ............................................................................................................ 19 6 Application Information .................................................................................................................... 21 6.1 Matching network of the transmitter .................................................................................................... 21 6.2 Reference crystal for the frequency synthesizer ................................................................................. 22 6.3 Loop filter components ........................................................................................................................ 22 6.4 Recommended modulation conditions ................................................................................................ 22 6.5 TYPICAL APPLICATION SCHEMATICS ............................................................................................ 23 7 Packaging information...................................................................................................................... 24 © Semtech 2007 Table of Contents 2 SX1223 www.semtech.com ...
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... MHz is user selectable for driving an external micro-controller. SX1223 comes in a RoHS green TQFN-24 package (body size mm). 1 FUNCTIONAL BLOCK DIAGRAM VDDF XTA VDD LDO CLOCK GEN LDO VDDP RFOUT PA BIAS © Semtech 2007 CRYSTAL LOOP FILTER XTB LD CPOUT OSCILLATOR LOCK DETECT ÷ M PFD PFD Open Loop OPAMP ...
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... VSSF - 23 VDDF - 24 CIBIAS OUT Note: Thermal Pad on the bottom of the package must be connected to ground. © Semtech 2007 Function Main analog power supply Max 3.6V in sv1-mode Max 2.5V in sv2-mode PA ground In sv1-mode: PA LDO output, capacitor needed In sv2-mode: PA power supply, max 2 output PA ground PTAT source bias resistor / PA start-up control capacitor Crystal oscillator pin & ...
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... Frequency range FDA Frequency deviation FDA_L Frequency deviation Variation of frequency FDA deviation BR Bit rate BR_3 Bit rate for mw3 mode SPICLK SPI clock frequency (SCK) © Semtech 2007 Min. -0.4 -55 Min. 2.0 -40 - Conditions Min - Crystal oscillator running, - CLKOUT off Frequency synthesizer ...
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... PHN Phase noise of the output signal CLKOUT Output clock VIH Digital input level high VIL Digital input level low © Semtech 2007 Conditions Min Highest programmable output 8 power RF output power step size - (8 steps available) Recommended value: 16 MHz - ...
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... There are two sets of each of these divide factors (M0, N0, A0 and M1, N1, A1). In modulation modes mw1 and mw2 (register bit Modulation1=0), only the M0, N0 and A0 are used to fix the carrier frequency. If modulation by using the dividers is selected (mw3, Modulation1=1, Modulation0=0), the two sets are used to program the two RF © Semtech 2007 f XCO ...
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... The VCO is fully integrated and has no external components. It oscillates at 1.8 GHz and is divided the 900 MHz or the 450 MHz band respectively (FreqBand = 1 or 0). Additionally two bits in the configuration registers set the VCO frequency and three bits control the bias current. The two VCO_freq bits have to be programmed by © Semtech 2007 XTA, pin 8 5p6 ...
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... The input capacitance is approximately 6 pF. For test purposes, the VCO can be bypassed by applying a differential local oscillator (LO) signal to the device on pin CPOUT and VARIN. A resistor proper biasing. The register bit VCO_by must be set to ‘1’. © Semtech 2007 VCO_IB1 VCO_IB0 VCO_freq1 VCO_freq0 1 1 ...
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... When designing a third order loop filter, the internal capacitance on the VARIN pin of approximately 6 pF must be taken into consideration. Figure 5b shows the loop filter configuration for the open loop VCO modulation case. © Semtech 2007 Comments VCO is phase-locked VCO is free-running Modulation inside PLL ...
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... Time diagram of the data interface in synchronous mode Figure 6: Before entering into transmit mode (mw1 or mw2 important to set DATAIN to high impedance. The data is provided directly to the modulation circuit and violation of this may cause abnormal behavior. © Semtech 2007 R2 VARIN, pin 21 CPO UT, pin 20 ...
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... Const : Const : Carrier frequency. C FreqBand: Frequency band. 0: 400MHz and 1: 900MHz. © Semtech 2007 f XTAL . Re fClk BRn BR 2 (VCO gain parameter of the radio chip, and is not controllable by the , is divided by RefClk_K to generate the modulator clock. Since this modulator FreqBand 12 SX1223 (4.1) (crystal oscillator frequency) is set XTAL (4 ...
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... Frequency deviation setting for MW3 In MW3 the modulation is done by switching between two frequency divider ratio sets: M The frequency f will be generated using the first set and frequency f 0 transmission of the two possible values ‘0’ and ‘1’. © Semtech 2007 Const f 2 FreqBand 1 ...
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... When LDO_en=0, the power supply range is 2.0 - 2.5 V (sv2). Power must be applied to pin and 23. In this case capacitors are only needed for normal noise decoupling. © Semtech 2007 and f 0 Output power ...
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... The SI line must stay high for at least one clock cycle on SCK to start a new write or read sequence. The typical current drive 2mA @ 2.7V, the maximum load is CLop. When the serial interface is not used for read or write operations, both SCK and SI should be set to “1”. Except in read mode set to “HZ”. © Semtech 2007 ...
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... Table 7: Contents of the configuration registers and their values at power-on 5.2.1 Operating Modes The SX1223 can be programmed into four different modes by the Mode1 and Mode0 bits, as illustrated in Table 8. Add Bits Mode1 Mode0 0 6 © Semtech 2007 Data Mode [1:0] PA [2:0] Freq_Band XCOcap_en LDO_en XCO_Quick_ XCO_High_ - PAC_en Start Current ...
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... RF frequency 850-950 MHz (default) Add Bit XCOcap_en Comments Internal capacitors for the crystal oscillator turned off Internal capacitors for the crystal oscillator turned on, external capacitors not needed 1 (default) © Semtech 2007 State PA0 21dB attenuation 0 18dB attenuation 1 15dB attenuation 0 12dB attenuation 1 9dB attenuation ...
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... Assuming FreqBand=1. When FreqBand=0, the RF frequency is halved. © Semtech 2007 Comments 0 Normal XCO bias current (default) 1 Higher XCO bias current 0 Quick start of XCO with normal bias current in steady state 1 Quick start of XCO with higher bias current in steady state Table 15: XCO start-up control ...
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... The two VCO_freq bits have to be programmed by the user according to the selected frequency band, whereas the three VCO_IB bits can be either forced by the user or set automatically by the circuit which will select the combination having the best phase noise. This automatic setting can be enabled by setting the three VCO_IB bits to ‘0’. © Semtech 2007 ...
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... PAbuffer bias current setting 1 0 PAbuffer bias current setting, highest bias current 1 1 Table 31: PA and PAbuffer bias current setting © Semtech 2007 Comment When VCO is bypassed, a differential signal can be applied to the circuit using pin CPOUT and VARIN Table 30: VCO bypass bit 20 SX1223 ...
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... Name Typical Value for 434 MHz CT1 CT2 CT3 CT4 LT1 Table 33: Typical component values for the recommended matching network at the output of the transmitter © Semtech 2007 434 MHz 869 MHz 19.4-j2.6 23.5-j1 CT2 CT3 LT1 Figure 9: Transmitter output network Typical Value ...
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... Semtech 2007 Min. value Typ. value - 16.0 MHz (fundamental Table 34: Crystal characteristics 12k 470pF 4.7nF 33nF Max. carrier ...
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... TYPICAL APPLICATION SCHEMATICS VDD C6 VDD Note: refer to chapter 4.3 for pin 6. Please contact Semtech for applications schematics and bills of materials for Reference Designs. © Semtech 2007 VDD SI 2 VSSP /EN 3 VDDP SCK SX1223 4 TQFN24 RFOUT DATAIN 4x4 5 VSSP DCLK 6 PTAT/PAC ...
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... PACKAGING INFORMATION SX1223 comes in a 24-pin RoHS green TQFN 4x4 package as shown in Figure 11 below. The exposed die pad on the bottom of the chip should be soldered. Please contact Semtech for foot print recommendations and PCB gerber files of Semtech reference designs. © Semtech 2007 ...
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... No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent or other industrial or intellectual property rights. Semtech assumes no responsibility or liability whatsoever for any failure or unexpected operation resulting from misuse, neglect improper installation, repair or improper handling or unusual physical or electrical stress including, but not limited to, exposure to parameters beyond the specified maximum ratings or operation outside the specified range ...