DEMO90121LR Melexis Inc, DEMO90121LR Datasheet
DEMO90121LR
Specifications of DEMO90121LR
Related parts for DEMO90121LR
DEMO90121LR Summary of contents
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... The form minimized to demonstrate the high level of integration allowed by the MLX90121. The bill of material for DEMO90121LR targets a cost of 30$ per component set for 1000 modules. Complete schematics, bill of material and layout are annexed to this document allowing a fast start for development work. Source ...
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... RFID Antenna Layout .......................................................................................................19 3 Introduction You purchased a DEMO90121LR. Thank you for choosing Melexis RFID solutions. This document contains the instructions to use and evaluate the functions and the performance of this demonstrator. All the necessary hardware is provided in the packaging box and the microcontroller on-board is pre-programmed with the firmware on the included CD ...
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... You will find in the box the following components. 1 RFID Reader Board • Power supply connector RS232 connector 1 Board antenna • 390129012104 Rev 003 RFID Long Range Demo User Manual Figure 1: RFID reader board. Top side Figure 2: Antenna ANT3_0 Page DEMO90121LR Antenna connector (SMA) User Manual Dec. 2009 ...
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... CD with the firmware and documentation • The delivered CD contains the complete documentation of the hardware and firmware for DEMO90121LR, User Manual, Datasheet MLX90121, Source Code of the firmware (written in C, flavor AVR gcc), Hex file of the firmware, Bill of materials of the board, UT121 software (PC user interface) 1 Box Content (on paper) • ...
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... R12 and the transistor M1 are anticipated in the layout to adjust the modulation depth on the fly by the microcontroller. This function is not used in the DEMO90121LR and these components are not mounted. To avoid any perturbation, the MLX90121 use its own 13.56MHz signal provided by the crystal resonator Y1. ...
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... R2OUT VCC 10 15 T2IN GND 11 T1IN C40 12 R1OUT 100NF 1 C+ 100NF 3 14 C1- T1OUT 4 8 C2+ R2IN C41 5 13 C2- R1IN T2OUT 6 V- 100NF C43 C44 MAX202CSE GND_Ser 1uF 100NF GND_Ser Page DEMO90121LR PFI RX232 RX485 RS232_485 C39 CON3 RS232 User Manual Dec. 2009 ...
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... RX485 8.5 Power supplies and LEDs The DEMO90121LR is supplied through the connector CON6. A protection diode D1 protects the board from supply inversion while a suppression diode D2 protects against over voltage. Two linear regulators have been chosen to provide clean power supplies of +12 volts for the power booster circuit and +5 volts for the MLX90121 and the microcontroller ...
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... SO MOSI SCK 6 SCK 3 |WP C29 7 |HOLD 100NF FM25C160 GND_uC GND_uC Figure 10: Serial memory R15 R16 CH_MOSI CH_RST R17 8 7 CH_SCK + + 10 9 CH_MISO ISP R19 GND_uC 1 2 100 Page DEMO90121LR R26 7K5 D10 MOSI RST SCK MISO User Manual Dec. 2009 ...
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... RST 8.8 Microcontroller ATmega8 The DEMO90121LR is controlled by an Atmel microcontroller ATmega8. It contains the firmware example written by Melexis to handle the RFID communication and the serial communication with a computer. The microcontroller also controls the progressive field increase (PFI) block, the external FRAM through the SPI serial interface, the RS232/RS485 selection and the LEDs ...
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... The loop antenna is matched to 50-ohm by using two capacitors Cs and Cp. The serial one Cs is used to adjust the resonance frequency and the parallel one is used to adjust the matching on 50-ohms at 13.56MHz. 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual Reset PC6 RST Reset ↔ ...
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... Rs has to be dimensioned to dissipate at least one watt. Moreover, the quality factor and the voltage swing of the capacitors which form the matching network have to be chosen as high as possible. Mica capacitors have quality factor of about 1000 and support voltage swing up to 200V. 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual Page User Manual Dec. 2009 ...
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... Firmware 9.1 Structure The firmware of the DEMO90121LR handles the RS232 serial communication with a computer as well as the communication with the MLX90121 RFID reader. It can be illustrated by the following flow chart. Common level Library Protocol oriented command Application-specific parsers (Parser.c) Protocol specific parsers (Iso15par.c) ...
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... Practical information The firmware of the DEMO90121LR is based on the FW121 library. (FW90121: Firmware description) This library provides the ISO15693 protocol functions as specific commands to control the MLX90121 and address its internal registers. At power-on or reset, the microcontroller IO ports, timers, ADC, and watch-dog, and the MLX90121 transceiver registers are configured for the ISO15693 protocol as described in the MLX90121 datasheet ...
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... Conclusion The DEMO90121LR is an example of a small, cost effective, and simple control module for long range applications, based on the Melexis 13.56MHz transceiver MLX90121. It can also be considered as an advanced starting point for developers who want to build their own customized system meeting their specific requirements ...
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... C45 100NF 3 1NF 1 BUTTON_RESET D9 BUTTON_RSTSOFT GND_uC GND_uC GND_uC 2 uC reset circuit Soft reset circuit GND_uC LEDgeneral R26 7K5 1 D10 2 GND_uC LEDs Page DEMO90121LR 30BQ060 SMD CON1 Or F1 Vpower 2 0451.500MRL 1 1 POWER D2 C7 Edge of the D1 and F1 SMBJ22A 10UF/TANTAL/35V board not 2 assembled in the same ...
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... RFID ANTENNA: 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual Antenna Page User Manual Dec. 2009 ...
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... D8,D9,D10 1 F1* J2*,J3*,J4*,J5*,J6*,J7*,J8* 9 J9*,J10* 2 TP1,TP2 5 L1,L6,L8,L9,L10 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual Value SMA Antenna connector Reset Push button RSTsoft Push button Power supply Connector RS485 Connector RS232 Connector ISP Connector Connector 5.5-50pF Trimming capacitor ...
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... CS3 1 CS4 1 CV2 1 RS2 1 RS1* *These components are not mounted. 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual 3.3uH Matching coil 0.27uH Matching coil PMBF170 10% modulation transistor FDC6327C Soft start PWM transistor IRFD110 Power booster transistor 4K7 Thick film resistor 0805 ...
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... RFID Antenna Layout 390129012104 Rev 003 DEMO90121LR RFID Long Range Demo User Manual Page User Manual Dec. 2009 ...