AS3991-BQFT austriamicrosystems, AS3991-BQFT Datasheet - Page 11

• Manufacturer Part Number: AS3991-BQFT
• Description: IC UHF RFID READER 64-QFN
• Manufacturer: austriamicrosystems

Specifications of AS3991-BQFT

• Rf Type: Read / Write
• Frequency: 840MHz ~ 960MHz
• Features: ISO-18000-6
• Package / Case: 64-VFQFN, Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: AS3991-BQFT; AS3991-BQFTTR

AS3990/AS3991
Data Sheet - D e t a i l e d D e s c r i p t i o n
7 Detailed Description
The RFID reader IC comprises complete analog and digital functionality for reader operation including transmitter and
receiver section with complete EPC Gen2 or ISO18000-6C digital protocol support. To integrate as many components
as possible, the device also comprises an on-board PLL section with integrated VCO, supply section, DAC and ADC
section, and host interface section. In order to cover a wide range of possibilities, there is also Configuration registers
section that configures operation of all blocks.
For operation, the device needs to be correctly supplied via. VEXT and VEXT2 pins and enabled via. EN pin (Refer
Supply on page 11
the configuration registers are preset to a default operation mode. The preset values are described in the
Registers Address Space on page 23
registers to choose other options.
The communication between the reader and the transponder follows the reader talk first method. After power-up and
configuring IC, the host system starts communication by turning on the RF field by setting option bit rf_on in the ‘Chip
status control register’ (00)
Transmitting and receiving is possible in the following two modes:
Supply
The effective supply system of the chip decreases the influence of the supply noise and interference and thus
improves de-coupling between different building blocks. A set of 3.4V regulators is used for supplying the reference
block, AD and DA converters, low frequency receiver cells, the RF part, and digital part. It is possible to use the digital
part supply VDD_D for supplying the external MCU with a current consumption up to 20mA. The input pin for the
regulators is VEXT. The output pins for regulators are VDD_A, VDD_LF, VDD_D, VDD_RFP and VDD_B. Each of the
pins require stabilizing capacitors to connected ground (2.2…10µF and 10…100nF) in parallel. Depending on quality
of the capacitors, 100pF could be required.
Figure 3. Mixer Supply
An additional 4.8V regulator is used for the input RF mixers supply. The input of this regulator is VEXT, output is
VDD_MIX pin. For correct operation of the 4.8V regulator, the VEXT voltage needs to be between 5.3V and 5.5V.
VDD_MIX needs de-coupling capacitors to VDD_MIX like other VDD pins.
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1. Normal Data Mode: In this mode, the TX and RX data is transferred through the FIFO register and all protocol
2. Direct Data Mode: In this mode, the data processing is done by the host system.
data processing is done internally.
for connecting to supply and
VEXT
(see Table 13)
below each register description table. It is possible to access and change
receive
On
and transmitting the first protocol command (Select in EPC Gen2).
LDO
Power Modes on page 12
Revision 3.81
Mixer
about operation of the EN pin). At power-up
Configuration
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