AS3977-BQFU austriamicrosystems, AS3977-BQFU Datasheet
AS3977-BQFU
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AS3977-BQFU Summary of contents
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... General Description The AS3977 is a low-power fully integrated ETSI, FCC and ARIB compliant FSK transmitter capable of operating at any ISM frequency in the range of 300 to 928 MHz based on a sigma-delta controlled fractional-N synthesizer phase locked loop (PLL) with fully integrated voltage controlled oscillator (VCO). The power amplifier (PA) output is programmable and can deliver power ranging from – ...
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... AS3977 Data Sheet - Figure 1. Block Diagram XTAL IN ÷4 XTAL OUT CLK Gen Baudrate Gen. MC CLK ÷T Deviation Data sync. DATA I/O CLOCK ENABLE www.austriamicrosystems.com VCCPLL VCC PA Phase Charge Loop detector pump filter VCO ΔΦ ±Q ÷ P ΣΔ ÷N RF Band ...
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... AS3977 Data Sheet - Contents 1 General Description.............................................................................................................................. 2 Key Features ........................................................................................................................................ Main Characteristics......................................................................................................................................... 1 Additional Features .......................................................................................................................................... 1 3 Applications .......................................................................................................................................... 4 Pin Assignments................................................................................................................................... Pin Descriptions ................................................................................................................................................... 5 Absolute Maximum Ratings.................................................................................................................. 6 Electrical Characteristics ...................................................................................................................... 7 Timing Characteristics ........................................................................................................................ Timing Parameters ............................................................................................................................................. 8 Detailed System Description .............................................................................................................. Reference Frequency Generator........................................................................................................................ Phase Locked Loop............................................................................................................................................ Gaussian Filter and Digital Modulator ................................................................................................................ ...
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... AS3977 Data Sheet - FSK Deviation Setting and Frequency Trimming ........................................................................................... 37 Baud Rate Generator ......................................................................................................................................... Reference Design PREOUT and PAOUT Connection ....................................................................................... Matching Circuit and PREOUT and PAOUT Connections to the Supply Voltage .......................................... 38 10 Measurement Results....................................................................................................................... Applicable Radio Standards ........................................................................................................................... 42 11 Package Drawings and Markings ..................................................................................................... 12 Ordering Information......................................................................................................................... ...
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... RESERVED 3 VCCPLL 4 ENABLE 5 www.austriamicrosystems.com MCCLK 1 12 DATAIO 2 11 AS3977 GND VDD 3 10 VREGDIG Type PREOUT Open Collector preamplifier output, need a feeding coil connected to VREGRF or VDD and is the input for the Power amplifier Open Collector power amplifier output, need a feeding coil connected to VREGRF or VDD ...
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... AS3977 Data Sheet - Table 1. Pin Descriptions Pin Name Pin Number CLK 6 XTALIN 7 XTALOUT 8 VREGDIG 9 VDD 10 DATAIO 11 MCCLK 12 VSS 13 Reserved 14 VCCPA 15 VREGRF 16 GND 17 www.austriamicrosystems.com Type CLK SDI clock VDD VDD XTAL oscillator input, DC Level approximately 1 Volt, needs an DC Blocker in case of external clock ...
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... AS3977 Data Sheet - Absolute Maximum Ratings Stresses beyond those listed under “Absolute Maximum Ratings“ may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated under “Operating Conditions” ...
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... AS3977 Data Sheet - Electrical Characteristics Table 3. Operating Conditions Symbol Parameter V Positive supply voltage analog SUP Negative supply voltage analog GND V Negative supply voltage digital SS Difference of supplies A-D Ambient Temperature T AMB Table 4. Block Specification Symbol Parameter f OUT315 f OUT434 Output Frequency Range f OUT868 ...
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... AS3977 Data Sheet - Table 4. Block Specification (Continued) Symbol Parameter Spurious Emissions P SPE2 1 excluding Harmonics Spurious Emissions 1 and Harmonics f Output Frequency Error ERROR 868MHz Frequency Band Section, EN 300 220 is applicable ΔFSK FSK Deviation 3 Spurious Emissions P SPE3 1 excluding Harmonics Spurious Emissions 1 and Harmonics ...
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... SUP T =-40…85ºC AMB crystal series resistance ≤ 100Ω f =13.56MHz, C =12pF 1500 XOSC L AS3977 Only depending on configuration register settings and crystal V =3V, at nominal high level SUP output current V =3V, at nominal high level SUP 0.9*V output current Conditions ...
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... AS3977 Data Sheet - Table 8. (Continued)Loop Filter Bandwidth Symbol Parameter @ 12.5 µ µA Charge pump f BW setting: I CHP @ 37.5µ µA Filter Bandwidth at 868 MHz @ 12.5 µ µA Charge pump f BW setting: I CHP @ 37.5µ µA Table 9. Power Amplifier (300 - 320 MHz and 425 - 450 MHz Bands) ...
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... AS3977 Data Sheet - Table 9. Power Amplifier (300 - 320 MHz and 425 - 450 MHz Bands) Symbol Parameter Max Output Power @ 50Ω P OUT 1. Limits by production test measurement uncertainties Table 10. Power Amplifier (865 - 870 MHz and 902 - 928 MHz Bands) Symbol Parameter Min Output Power ...
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... AS3977 Data Sheet - Table 11. Antenna Tuning Circuit Symbol Parameter Maximum Antenna tuning Capacitor C Atmax Table 12. Low Power Reset (Bit LT) Symbol Parameter Low Power Detection V LPR Threshold Voltage Low Power Release Threshold V LPR Voltage Table 13. Low Supply Voltage Detector (Bit LS) Symbol Parameter ...
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... AS3977 Data Sheet - Table 16. Current Consumption Symbol Parameter Transmit Mode @ 8dBm output power, 315 MHz band @ 50Ω ITX8dBm including matching 315 network, strong AB operation Transmit Mode @ 8dBm output power, 433 MHz band @ 50Ω ITX8dBm including matching 433 network, strong AB operation Transmit Mode @ 4dBm ...
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... AS3977 Data Sheet - Timing Characteristics Be aware that the Power Down Mode can be entered by setting ENABLE low for more than 2 Down Timer). Figure 3. Write Data ENABLE CHD CLK CLK polarity MCCLK DATAI behavior DATAO Figure 4. Read Data ENABLE CLK DATAI DATAI DATAO www ...
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... AS3977 Data Sheet - Timing Parameters Table 18. Timing Parameters Symbol Parameter General BR Bit rate SDI t Clock high time CH Clock low time t CL Write timing t Data in setup time DIS t Data in hold time DIH t Enable hold time EH Read timing t Data in to high impedance delay ...
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... Temperature = TS < 9…0 > * 0.19 – 50 The temperature sensor can be used to compensate the crystal drift over temperature. Note: AS3977 has the same temperature than the crystal only at start up and the temperature will increase immedi- ately thereafter due to self heating. Temperature sensor must be used only in the Clock Enable Mode as a stand alone block mandatory to be used with the PLL and Power Amplifier switched off ...
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... This interface enables a serial and synchronous communication between external microcontroller and AS3977. Data can be written to and read out from AS3977. Additionally, it facilitates the transmission of TX-data. The rising edge on the SDI enable signal (transition to the active state), while the device is in Power Down Mode has various effects on the circuit wakes up the crystal oscillator (this takes maximum 1 ...
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... Operation Modes All modes are controlled by the SDI interface. Power Down Mode The AS3977 is connected to the power supply and can be switched to power down mode. The current consumption is limited by the leakage current. Clock Enable Mode In this mode, only the reference frequency generator is switched on and a clock signal is supplied via the clock output ...
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... The selection of the active output frequency and/or power level and modulation type is done using the so-called command byte additional feature, the AS3977 provides a configurable clock signal derived from the crystal frequency. The purpose of this clock signal is to provide a µC clock and to enable data synchronization. ...
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... For example the first rising edge of SDI enable SDI clock is LOW, then each bit is transferred from the microcontroller on the rising edge of SDI clock and it is sampled from AS3977 on falling edge of the SDI clock. This is valid for read as well as for write commands. ...
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... Enable LOW pulse (duration: min > 1 SDI CLK cycle, max: < 1/f Power On Reset For stable start up of the AS3977 and to avoid unwanted crystal oscillation strongly recommended to perform a power on reset (Hardware Reset Method). This can be performed as described in every time when the supply voltage is less than the minimum allowed value Table 19 ...
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... ENABLE rises, DATAI is sampled at the rising edge of CLK. Consequently, data to be read from the microcontroller are driven by the slave (AS3977) at the transfer edge and sampled by the master (µC) at the sampling edge of CLK. An Enable LOW pulse has to be performed after register data has been transferred in order to indicate the end of the READ command and prepare the Interface to the next command control Byte ...
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... Figure 11. Reading of Data with Auto-Incrementing Address ENABLE CLK DATAI (µC Driven DATAO (AS3977 Driven DATAIO Data D7-D0 at Address A5-A0 is transferred here www.austriamicrosystems.com 16 clock cycles to keep DATAIO line driver control changes from microcontroller to AS3977 Data D7-D0 at Address A5-A0 is transferred to the Output Register of AS3977 ...
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... AS3977 Data Sheet - Transmitting Data Command code has to be provided from LSB to MSB and for transmit it is <C0, C1> = “11”. After the command code, further configuration has to be provided from the MSB to the LSB. Then a bit-stream, the data to be sent, can be transferred from the SDI master by keeping SDI enable signal to high ...
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... AS3977 Data Sheet - When the circuit is in Power Down Mode, the crystal oscillator and all the other analog/digital circuits are OFF. The transmitter interface is the only supplied circuit and it is sensitive to SDI signals. The current consumption is limited by the leakage current. The configuration registers do not alter as long as the minimum supply requirements are met. The state can only be left by the rising edge of ENABLE ...
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... AS3977 Data Sheet - The state can be left at the falling edge of ENABLE, or increasing the Supply Voltage above the threshold and setting the register bit (LT) to zero. The control of the power amplifier is determined by the command byte (bit A4 and A5). Table 20. PA Control Modes State ...
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... AS3977 Data Sheet - The first byte of every SDI sequence is the command byte. Function Code The function code defines the command to be performed Bit <A1, A0> Transmitter Configuration Register All configuration registers are readable and writable. The registers are arranged as addressable bytes. The first byte (A< ...
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... AS3977 Data Sheet - Table 22. Configuration Registers INT3<5:0> reserved I DF<7:0> PAOP1 J RPAOV1 <1:0> K PREOP2<4:0> PSC MCCDS L CLKS<1:0> <0> <2:0> M reserved ASC<1:0> N reserved O reserved Default settings given are recommendations according to application note (not set at power up). Table 23. Configuration Registers Description Register Name Synthesizer section A< ...
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... AS3977 Data Sheet - Table 23. Configuration Registers Description Register Name B<0> B<1> SD3 B<2> B<3> PN9INT B<4> B<15:5> FRAC1 <15:0> C<4:0> C<14:5> INT1<9:0> C<15> PLLON FRAC2 D<15:0> <15:0> E<9:0> INT2<9:0> E<15:10> FRAC3 <15:0> F<9:0> F<15:10> INT3<9:0> G<3:0> G<15:4> FRAC4 <15:0> H<3:0> H<13:4> ...
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... AS3977 Data Sheet - Table 23. Configuration Registers Description Register Name RPAOV1 J<12:11> <1:0> PAOP1 J<14:13> <1:0> J<15> PREOP1 <4:0> K<3:0> K<4> FSK1 K<5> LT K<6> LS RPAOV2 K<8:7> <1:0> PAOP2 K<10:9> <1:0> PREOP2 K<15:11> <4:0> L<0> FSK2 L<7:1> - Baud Rate Generator, Data Generator and Digital Test Multiplexer section MCCS L< ...
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... LT (Lock Transmit) The Lock Transmit bit will be set each time the circuit goes in Power Down Mode. When the bit is set, the power amplifier of the AS3977 cannot be activated. TX commands will be anyway accepted but without any “external” and visible effect. A low has to be written before starting any RF-Transmission. The first write command can be responsible for a wake up event of the circuit and to release Power Down Mode, which will lead to the inactive state ...
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... AS3977 Data Sheet - (Low Power Supply Voltage) Low power Supply voltage (LS read/write bit, which indicates that the power amplifier supply voltage level (VCCPA) is below a certain threshold voltage threshold level (plus a hysteresis), this bit has to be reset to zero via SPI. The bit condition has no influence on the operation of the IC ...
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... AS3977 Data Sheet - The reference frequency should be in the range MHz and can be calculated by: The recommended setting of the divider is 4. The next step is to calculate the Division ratio: DR This division ration can be split into a part before the comma, called integer part and a part after the comma, also ...
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... AS3977 Data Sheet - The value of f should be in the range of 3 MHz MHz to achieve an optimum on noise performance and REF current consumption M-counter and Value of INT<9> The value of the M-counter is given by: The Bit INT<9> can be calculated as, INT < 9 > N-counter and Value of INT<3:0> ...
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... AS3977 Data Sheet - INT < 7:4 >= AC-1= 5-1=4 Hex „4“ 16 FRAC < 15:0 > 0,48 x 65536 = 31457 =Hex “7AE1” FRAC Optional Frequency Calculation with Overlapping Fractional Bands by Using the Bit INT<8> Bit INT<8> The bit INT<8> multiplier to the output of the ΣΔ-modulator. Set this Bit to high stretches the fractional-N region by two and results in overlapping frequency bands with a bandwidth of 2*f frequency modulation and/or frequency trimming independently on the required output frequency and selected crystal ...
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... AS3977 Data Sheet - case, the value of the A-counter is zero, the value of the A-counter has to be increased by M and the value of N has to be decreased by one In case, the N-counter is in the range from and the value of the A-counter is less than N-counter-14: Note: In case, no solution can be found for the wanted center frequency, it may help to modify the reference fre- quency or INT< ...
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... Figure 13 shows the Power Line Matching and Transformation Network used on the Reference Design. the values for several settings, varying the operation frequency and the Supply Voltage source. Supply blocking capacitors are not shown in the schematic Figure 13. Schematic AS3977 2 PAOUT 1 PREOUT www.austriamicrosystems.com (see Figure 13) ...
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... AS3977 Data Sheet - Table 25. Part List of the Reference Design Components Supply voltage 2V regulated Source is VREGRF (pin 16) 315 MHz Compone Value Murata-LQW18AN47NG00 Murata-LQW18AN62NG00 Murata-GRM1885C1H100JA01 Murata-GRM1885C1H2R7CZ01 C2 2.7 pF Murata-LQW18AN56NG00 Murata-GRM1885C1HR50CZ01 C1 0.5 pF 433 MHz Murata-LQW18AN24NG00 Murata-LQW18AN33NG00 Murata-GRM1885C1H100JA01 Murata-GRM1885C1H2R2CZ01 C2 2 Murata-LQW18AN43NG00 Murata-GRM1885C1H2R7CZ01 C1 2.7 pF 868/915 MHz Toko-LL1608- ...
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... AS3977 Data Sheet - Measurement Results Figure 14. Output spectrum with 7.5MHz span, Frequency=433.92MHz, P cable attenuation), Span=7.5MHz Figure 15. Phase-noise: - 88.5dBc, P OUT www.austriamicrosystems.com =8dBm (0.3dBm added due to OUT =8dBm Revision 3 ...
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... AS3977 Data Sheet - Figure 16. Modulated signal with bypass gaussian filter, Freq Mod: 5kHz, Deviation: 10kHz Figure 17. Modulated signal with gaussian filter, Freq Mod: 5kHz, Deviation: 10kHz www.austriamicrosystems.com Revision 3 ...
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... AS3977 Data Sheet - Figure 18. Occupied bandwidth with bypass gaussian filter, Occupied bandwidth: 49.7kHz, Freq Mod: 5kHz, Deviation: 10kHz Figure 19. Occupied bandwidth with gaussian filter, Occupied bandwidth: 30kHz, Freq Mod: 5kHz, Deviation: 10kHz Applicable Radio Standards ARIB STD-T67 (Telemeter, Telecontrol and Data-Transmission Radio Equipment) ...
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... AS3977 Data Sheet - Package Drawings and Markings The device is available in a 16-Lead QFN (4x4mm) package. Figure 20. Package Drawings Top View PIN ator 4,0 QFN 16 QFN 16 4 mm) Top View Side View 0,75 0,95 Land pattern recommendation for JEDEC MO-220 VGGC Exposed paddle ...
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... AS3977 Data Sheet - Ordering Information The devices are available as the standard products shown in Table 27. Ordering Information Device ID Part Number AS3977B-BQFU AS3977-TPD AS3977B-BQFT 1. Dry Pack sensitivity Level =3 according IPC/JEDEC J-STD-033A. Where: T=Temperature range: B=-40…85 degree P=Package Type: QF=QFN D=Delivery Form U=Tube T=Tape and Reel www ...
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... AS3977 Data Sheet - Copyrights Copyright © 1997-2009, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. ...