AS3910-BQFT austriamicrosystems, AS3910-BQFT Datasheet
AS3910-BQFT
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AS3910-BQFT Summary of contents
Page 1
... With austriamicrosystems’ unique antenna management technology it is optimized for applications with directly driven antennas. The AS3910 is unequalled in the domain of HF Reader ICs in that it contains two differential low impedance (1.5Ω) antenna drivers. These drivers are unmatched meaning the IC can deliver times the output power of a standard HF Reader IC using the same power supply voltage ...
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... AS3910 Data Sheet - Figure 1. AS3910 HF RFID Reader IC Block Diagram XTO XTI Oscillator Logic FIFO FIFO Control Logic SPI SPI Interface Framing AS3910 HF RFID Reader IC Block Diagram www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Regulators Bias Transmitter Phase & A/D Converter Amplitude Detector Receiver External Field Detector Revision 2.3 ...
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... SPI Operation MODE Bits ......................................................................................................................................................... 17 8.9.3 Writing of Data to Addressable Registers (WRITE Mode) ......................................................................................................... 17 8.9.4 Reading of Data from Addressable Registers (READ Mode) .................................................................................................... 18 8.9.5 Sending Direct Commands ........................................................................................................................................................ 19 8.9.6 Loading Transmitting Data into FIFO ......................................................................................................................................... 19 8.9.7 Reading Received Data from FIFO ........................................................................................................................................... 19 8.9.8 Interrupt Interface ...................................................................................................................................................................... 19 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 ....................................................................................................................................... 16 Revision 2 ...
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... Calibrate Antenna Resonance ................................................................................................................................................. 42 8.17 Transparent Mode ............................................................................................................................................................................ 43 8.18 Active Receive – Use in ISO-14443B Anticollision 8.19 ISO-14443B, Reduction of TR0 and TR1 and Suppression of EOF/SOF in PICC Response 8.20 Test Pins ........................................................................................................................................................................................... 44 9 Package Drawings and Markings ........................................................................................................................................... 45 10 Ordering Information ............................................................................................................................................................. 47 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 ................................................................................................................................................. 38 ............................................................................................................................................... 40 ............................................................................................................................ 40 ................................................................................................................ 41 .......................................................................................................................... 44 Revision 2.3 ......................................................... ...
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... VDD 8 VSP_RF 9 RFO1 10 RFO2 11 VSN_RF 12 TRIM1_3 13 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 AS3910 Pin Type Digital bidirectional Test IO pin Enable input Digital input with pull-down Test input Digital input with pull-down Xtal oscillator output Analog output Xtal oscillator input Analog input Supply Digital ground Analog supply, regulator output ...
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... SDATAO 29 SDATAI 30 SCLK 31 SEN 32 VSUB exposed pad www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Pin Type Input to trim antenna resonant circuit Analog input Analog input Input to trim antenna resonant circuit Input to trim antenna resonant circuit Analog input Input to trim antenna resonant circuit Analog input Input to trim antenna resonant circuit ...
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... Input pin voltage (all except TRIM pins), (V Input pin voltage TRIM pins INTRIM Input current (latchup immunity SCR ESD Total power dissipation (all supplies and outputs Storage temperature strg Package body temperature body Humidity non-condensing www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Electrical Characteristics on page 8 Min Max Units - -100 100 mA ± ...
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... SENL T SCLK low SCLKL SCLK high T SCLKH T SEN rising to SCLK rising SENCLKR T SCLK falling to SEN falling SENCLKF www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Conditions Min In case power supply is lower than 2.6V, PSSR can not be improved 2.4 using internal regulators (minimum regulated voltage is 2.4V) 0 -40 Conditions Min 0 ...
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... Power on Reset Voltage POR V AGD voltage AGD V Regulator drop AR T Oscillator start-up time OSU 1. Amplitude of carrier signal at RFI inputs is 2.5Vpp, maximum amplitude is 3Vpp. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Conditions Min 13.56 MHz Xtal used, MCU_CLK disabled 13.56 MHz Xtal used, MCU_CLK disabled I =10mA RFO All segments ON 1 ...
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... AS3910 Data Sheet - Detailed Description Figure 3. Minimum Configuration with Single Sided Antenna Driving µC Figure 4. Minimum Configuration with Differential Antenna Driving µC www.austriamicrosystems.com/HF_RFID_Reader/AS3910 +3.3V VDD AGD EN SEN VSS SDATAO SDATAI VSP_A SCLK INTR VSN_A MCU_CLK VSN_D TEST VSP_RF XTI VSN_RF XTO ...
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... The transmitter block additionally contains a subblock, which modulates transmitted signal for communication reader to transponder (OOK or configurable AM modulation). The AS3910 transmitter is indented to directly drive antennas (without 50Ω cable, usually antenna is on the same PCB). Operation with 50Ω cable is also possible, but in that case some of the advanced features are not possible. ...
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... SDATAO pin; signal applied to SDATAI pin is directly used to modulate the transmitter. 7.0.10 FIFO The AS3910 contains a 32byte FIFO. Depending on the mode, it contains either data that has been received or data that transmitted. 7.0.11 Control Logic The control logic contains I/O registers, which define the operation of device. ...
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... The AS3910 operating mode is defined by the content of the Operation Control Register (address #01). At power up, all bits of the Operation Control Register are set to 0 and the AS3910 is in Power-down mode. In this mode – the AFE static power consumption is minimized, only the POR and part of bias are active, regulators are transparent and are not operating. The SPI is still functional in this mode ...
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... PM demodulation is done by processing phase signal coming from the Phase Detector. 8.4 A/D Converter The AS3910 contains an 8 bit successive approximation A/D converter. Input to A/D converter can be multiplexed from different sources to be used in several direct commands and adjustment procedures. The result of last A/D conversion is stored in a register which can be read through the SPI interface (address #0D). Typical conversion time is 12μ ...
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... A feedback loop is controlling the bias current in order to regulate amplitude on XTI pin to 1Vpp. This feedback assures reliable operation even in case of low quality crystals with 50Ω. In order to enable a fast reader start-up an interrupt is sent when oscillator amplitude exceeds 750mVpp. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Revision 2 ...
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... Power Supply, Regulators The AS3910 includes two regulators which can be adjusted automatically to improve the reader PSRR. VDD is an external power supply pin used to supply the logic and digital pins. One regulator is used to supply analog blocks (VSP_A), another is there just for transmitter (VSP_RF) in order to decouple transmitter current spikes from the rest of the IC ...
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... Figure 5. Writing of a Single Byte (falling edge sampling) SEN SCLK SDATAI SCLK raising Two leading edge data is Zeros indicate transferred from WRITE Mode µC www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Signal Level SPI Enable CMOS Serial Data input CMOS Serial Data output CMOS CMOS Clock for serial communication Register Address ...
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... SPI master has to keep the SEN signal high and the SCLK has to be active as long as data need to be read from the slave. SDATAI is sampled at the falling edge of SCLK (like shown in the following diagrams), data to be read from the AS3910 internal register is driven to SDATAO pin on rising edge of SCLK and is sampled by the master (μC) at the falling edge of SCLK. ...
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... INTR pin signal transitions to low. Note: There may be more then one Interrupt Register bit set in case the microcontroller did not immediately read the Interrupt Register after the INTR signal was set and another event causing interrupt occurred. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 C5 C4 ...
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... Transmit and receive capability the AS3910 is not limited by of the FIFO size due to a FIFO water level interrupt system. During transmission an interrupt is sent (interrupt due to FIFO water level) when the content of data in the FIFO which still need to be sent is lower then the FIFO water level for receive ...
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... Transparent mode 8.10.1 Set Default This direct command puts the AS3910 in the same state as power-up initialization. All registers are initialized to the default state. Please note that results of different calibration and adjust commands are also lost. This direct command is accepted in all operating modes. ...
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... Such a sequence is always in place in case of the ISO-14443 reader mode and also in case of the NFCIP mode where the AS3910 is the initiator. In case of the NFC target mode this sequence is started by receiving the interrogator request. After the interrupt caused by the first initiator request command Unmask Receive Data is sent to force the AS3910 in receive mode ...
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... There are two types of registers implemented in the AS3910: configuration registers and display registers. The configuration registers are used to configure the AS3910. They can be written and read through the SPI (RW). The display registers are read only (RO); they contain information about the AS3910 internal state which can be accessed through the SPI. ...
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... Initial NFC Target mode 3 nfc_t Note: Receive low power operation sacrifices the input sensitivity for low consumption consumption is reduced from 10mA to 5mA, then a 10mA reader operation is possible. Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function tx_rate1 tx_rate0 bit rate 106kb/s ...
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... Note: Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function 1 → only RFO1 driver will be used 1 → input applied to RFI1 is envelope 1 → reduces the gain for first stage after peak detector 1 → reduces the gain for first stage after peak detector 0 → ...
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... AM demodulation 0 → OOK, 1 → Not used → 28, 1 → fifo_lr 0 0 → → fifo_lt 0 Not used 0 Note: Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function egt1 egt0 number of EGT EGT time defined in number of etu - - - - - - ...
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... Note: Default setting is set at power up and after Set Default command, filter selection bits are preset also when ISO mode or receive data rate change. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function rg0 Gain reduction fs0 Filter Selection Comment ISO-14443A 106 kb/s Automatic preset 0 1 ISO-14443B 106 kb/s ...
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... Number of bytes (binary coded) in the FIFO which were not read out 4 fifo_b2 3 fifo_b1 2 fifo_b0 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function Function Set after enable Set when nfc_t is 1 and en=0 informing that an RF field has been detected, Set when transmission could not be done due to detection of RF field during RF Collision Avoidance Set during receive, informing that FIFO is almost full and has to be read out ...
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... ISO-14443 anticollision frame 0 antcl 0 Note: Bits frm4 and antcl are cleared after transmission is performed. Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function By reading this bit it can be checked whether transponder is answering. See also Application Notes (Active receive). Function Function ...
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... Address # 0D: A/D Output Register Bit Name 7 ad7 6 ad6 5 ad5 4 ad4 Displays results of A/D conversion. 3 ad3 2 ad2 1 ad1 0 ad0 Note: At power up and after Set Default command, content of this register is set to 0. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function Maximum supported number of bytes is 1023 Function Revision 2.3 type: RW Comments type: R Comments ...
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... Not used 1 0 Note: Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function MSB This register stores result of Calibrate antenna command. LC trim switches are defined by data written in this register in case trim_s=0. A bit set to 1 indicates that corresponding transistor on TRIM1_x and TRIM2_x pin is switched on. ...
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... Note: Default setting is set at power up and after Set Default command. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function Function MSB Displays result of Calibrate Modulation Depth command. Antenna drivers are composed of 8 binary weighted segments. Bit md_x set to one indicates that this particular segment will be disabled during AM modulated state ...
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... Function MSB Antenna drivers are composed of 8 binary weighted segments. Setting a bit droff to 1 will disable corresponding segment during normal non-modulated operation. LSB Function Threshold used to detect presence of interrogator magnetic field. See threshold definition. Threshold used to detect presence of external field during collision avoidance. See threshold definition ...
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... AS3910 Data Sheet - Table 31. Target Activation Threshold as seen on RFI1 Input trg_l3 trg_l2 Table 32. Collision Avoidance Threshold as seen on RFI1 Input rfe_3 rfe_2 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 trg_l1 trg_l0 rfe_1 rfe_0 Revision 2.3 Target activation threshold voltage [mVpp on RFI1] 220 220 190 175 155 145 Collision avoidance ...
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... Table 35. Definition reg_3 reg_2 rege_3 rege_2 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Function This register displays actual regulated voltage when regulator is operating. In Power-down mode, its content is forced to 00. See Table 35 for definition. Function Defines mode of regulator voltage setting External definition of regulated voltage. See reg_1 reg_0 rege_1 rege_0 Revision 2 ...
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... Target activation detector output in case nfc=1 2 gr_2 gr_2 1 gr_1 gr_0 - 1 Note: At power up and after Set Default command, content of this register is set to 0. rssi_3 rssi_2 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 reg_1 rege_1 0 other combinations Function gr_1 gr_0 Gain reduction rssi_1 Revision 2.3 reg_0 Regulated voltage rege_0 [V] 1 2.4 2 ...
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... Typical Operating Sequence At power up the AS3910 enters in the Stand-by mode. Content of all registers is set to the default state which is in most cases 0. First action of the microcontroller after a power-up should be to load the ISO Mode Definition Register and the configuration registers to con- figure reader operation ...
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... Target Activation Detector can be turned off by setting bit nfc_t low after presence of the initiator field is detected. Next the direct command Unmask Receive Data has to be send to put the Receiver and control logic in the receive mode. The AS3910 is now ready to receive request from the initiator ...
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... ATQA (answer to REQA or WUPA). When the bit collision is detected an interrupt is sent (INTR due to collision) and the bit at which collision occurred is indicated in the Collision Register (#0A). In case of anticollision frame (indicated to the AS3910 by bit 0 of register #0B) the bit collision position displayed in Collision Register is counted from beginning of anticollision frame (including the part which is transmitted) ...
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... Receiving 4Bit Tag Response Frame Mifare Ultralight tag uses 4 bit response frame to indicate ACK and NACK. The AS3910 framing expects that response frame is composed of bytes (except in case of anticollision frame) and it rejects a 4 bit response frame as an error (error due to receive data coding). By setting the bit 1 (frm4l) of register #0B bit response frame is correctly processed and put in FIFO (MSB bits of first byte) ...
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... Level Definition Register (#12) while the register #13 is restored with the non-modulated level definition value. 8.16 Antenna LC Tank Resonance: Checking and Calibration The AS3910 comprises the building blocks which make possible checking and adjustment of the antenna LC tank resonance frequency. The arrangement of these building blocks and associated adjustment procedure are patent pending. ...
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... Figure 10. Connection of Trimming Capacitors to the Antenna LC Tank in case of Single (left) and Differential Driving (right) TRIM 1_0 TRIM 1_1 TRIM 1_2 TRIM 1_3 RF01 RF02 RFI 1 RFI 2 TRIM 2_3 TRIM 2_2 TRIM 2_1 TRIM 2_0 www.austriamicrosystems.com/HF_RFID_Reader/AS3910 TRIM 1_0 TRIM 1_1 TRIM 1_2 TRIM 1_3 RF01 RF02 Antenna RFI 1 RFI 2 TRIM 2_3 TRIM 2_2 TRIM 2_1 TRIM 2_0 Revision 2 ...
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... Transparent Mode The AS3910 framing supports the ISO-14443 standard. Other standard and custom 13.56MHz RFID reader protocols can be realized using the AS3910 AFE and framing implemented in the external microcontroller. After sending the direct command Transparent Mode the external microcontroller directly controls the transmission modulator and gets the Receiver output (control logic becomes “ ...
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... Test Pins Pins TEST and TIO are used to test the AS3910. Pin TEST is a digital pin with pull down used to enter the test mode, pin TIO is used in test mode as a digital IO, in normal mode tristate recommended to connect pin TEST to VSS and to leave pin TIO open. ...
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... Dimension b applies to metallized terminal and is measured between 0.25 and 0.30mm from terminal tip. Dimension L1 represents ter- minal full back from package edge up to 0.1mm is acceptable. 4. Coplanarity applies to the exposed heat slug as well as the terminal. 5. Radius on terminal is optional. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Max Symbol Min ...
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... July 01, 2009 July 15, 2009 2.2 Sep 08, 2009 Oct 09, 2009 2.3 Jan 15, 2010 Feb 11, 2010 Note: Typos may not be explicitly mentioned under revision history. www.austriamicrosystems.com/HF_RFID_Reader/AS3910 Owner Mark Maks Complete datasheet updated Mauro Updated ordering information 1) Parameter values updated in 2) Updated bits 5,4 in Table 12 3) Updated “ ...
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... Ordering Information The devices are available as the standard products shown in Table 38. Ordering Information Ordering Code AS3910-BQFT HF RFID Reader IC Note: All products are RoHS compliant and Pb-free. Buy our products or get free samples online at ICdirect: For further information and requests, please contact us: or find your local distributor at http://www ...