AS3990

Description

The AS3990/91 UHF reader chip is an integrated analogue front end and data framing system for a 900MHz RFID reader system. Built in programming options make it suitable for a wide range of applications in UHF RFID systems. Designed to simplify the design and implementation of an EPC Class1 Gen2 reader, this IC requires only a standard 8Bit microcontroller with minimal other components.

The AS3990/91 comprises the EPC Class 1- Gen2 protocol (ISO 18000-6c) with digital high speed logic up to the framing level and supports the ISO 18000-6a and ISO 18000-6b Protocol with direct data mode. The Interface to the microcontroller can be either a 4 pin serial data Interface (SDI) or alternatively in case of high data rates are necessary an eight Bit parallel. The frame management will be done using a 12 Byte FIFO in order to decrease processor workload and ensure a smooth data stream and correct protocol handling. All low level transmission codec’s and CRC generation is done internally.

Key Features

• Fully compliant with ISO 18000 6a, 6b, 6c and EPC Class 1- Gen2 protocol using external MCU
• EPC Class 1 -Gen2 framing support using low cost 8 Bit microcontroller
• Direct data mode in the frequency range of 860 to 960 MHz enables propriety Protocol support
• Internal power amplifier with level controlled 20dBm for short range applications (only available on the AS3991)
• Modulator using ASK or PR-ASK modulation
• Adjustable ASK modulation index
• Automatic selection between I and Q Signal ensuring no “communication holes”
• Built-in reception low-pass and high-pass filters having selectable corner frequencies.
• On chip VCO and PLL covering complete RFID frequency range and frequency hopping support
• Selectable receiver gain with AGC
• Supported link frequencies from 40 up to 640kHz

Applications

• Barcode label printers
• Add-on module for handheld computers, PDA
• Point of sales
• Currency reader
• UHF RFID reader systems
• Hand-held UHF RFID readers
• Toll systems
• mobile phones