AS399x UHF Pico Reader - Digi-Key Notes/austriamicrosystems... · [v1-00] 2014-Jul-24 Document Feedback AS399x UHF Pico Reader ... o Between the Controller and the AS399x is SPI via

Application Note DN[Document ID]

ams Application Note, Confidential Page 1

[v1-00] 2014-Jul-24 Document Feedback

AS399x UHF Pico Reader

Demo Board Description

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AS399x UHF Pico Reader Demo Board Description



Content Guide

1 General Description ............................................................................................................. 3

2 Key Features ........................................................................................................................ 3

3 Applications .......................................................................................................................... 4

4 Reader System Overview .................................................................................................... 5

4.1 Reader Part Overview .......................................................................................................... 5

4.2 Controller Part Overview ...................................................................................................... 7

5 Schematics and Layouts .................................................................................................... 10

5.1 Schematics ......................................................................................................................... 10

5.1.1 Controller Schematic .......................................................................................................... 10

5.1.2 Reader Schematic.............................................................................................................. 10

5.2 Layouts ............................................................................................................................... 12

5.2.1 Controller PCB Layout ....................................................................................................... 12

5.2.2 Reader PCB Layout ........................................................................................................... 13

6 Impedance Matched Tracks ............................................................................................... 14

6.1 Track Impedance Calculation ............................................................................................ 15

6.2 Reader PCB Stack Up ....................................................................................................... 15

7 Bill of Materials ................................................................................................................... 16

7.1 Controller BOM .................................................................................................................. 16

7.2 Reader BOM ...................................................................................................................... 17

8 Contact Information ............................................................................................................ 19

9 Copyrights & Disclaimer ..................................................................................................... 20

10 Revision Information .......................................................................................................... 21





1 General Description

The PICO Reader from ams AG is a small form factor and low costs EPC Class 1 Gen 2 compliant

UHF RFID demonstration reader system. Leveraging the AS399x family of UHF RFID Reader IC’s,

provides close to the industry’s lowest BOM cost, best in class power consumption with the least

amount of complexity.

Second only to ams AG PICO design the low reader BOM enables UHF RFID markets that have

previously been out of reach due to cost restraints. With regards to overall cost vs. performance the

PICO UHF RFID demo reader is unmatched in the industry.

With an internal PA delivering up to 20 dBm, it is ideally suited for those applications that have similar

cost constraints but require that extra power.

The PICO demo reader comes in two parts namely the analogue (reader) and digital (controller) parts.

The user can separate the two stacked boards to fully prove out their own RF and digital parts. With

this set up it also means the user can evaluate the suitability of RFID in their current system.

The reader portion is designed such that it can be easily connected to a host MCU via SPI. The high

level of integration found on the AS399x UHF RFID Reader IC’s allows for minimal code loading and

quick implementation.

The designs come with free, fully portable code and all Gerber data and schematics. This allows for

a quick, trouble free design in.

2 Key Features

Interface

o Between the Controller and Host Computer: USB (optional UART)

o Between the Controller and the AS399x is SPI via a low cost pin header connection

o Between the RF board and the Antenna we use a U.FL (50 Ohm) SMA (Male)

5V power supply from USB.

GUI

o Adjust Output Power

o Adjust Receive – Sensitivity

o Adapt to different frequency schemes

o Change Gen2 specific parameters like BLF, Coding, Anti-Collision Slots, …

o Diagnostic Features: RSSI Measurement, Reflected Power Measurement

o Support for sending direct commands

o Advanced Tag Manipulations: R/W to different memory banks, define passwords

o Associate tags with other applications like media player





o View and easily manipulate register settings with advance tool tip text.

Power Consumption: complete reader system: 1.5W (max)

Available with both the AS3991 and AS3992

Fully Gen 2 compliant, ISO 18000-6b & c

Differential Tx chip-output configuration

Internal Power Amplifier

Maximum output power 20 dBm scalable in 20 steps

Single – ended Rx chip-input configuration

Low cost MCU: Silabs (C8051F340-GQ)

Indicator LED

3 Applications

Typical applications for the PICO demo reader include:

Embedded Consumer Applications

Mobile Applications (Low Power Handheld, PDA’s, Smart Phones)

Embedded Industrial Applications

Gaming

Desk top readers

Low/Mid powered modules





4 Reader System Overview

4.1 Reader Part Overview

Figure 1: Reader PCB - Top View

1. AS399x UHF RFID reader IC (austriaPicosystems)

2. Balun 2:1 (Johanson Technology)

3. Directional coupler / Low pass filter combination (Johanson Technology)

4. U.FL antenna port (Hirose)

5. Loop Filter

6. OAD pins for debugging purposes

7. Crystal

2

3

5

4

6

1

7





Figure 2: Reader PCB - Bottom View





4.2 Controller Part Overview

Figure 3: Controller PCB - Topview

1. MCU C8051F340 (Silabs)

2. USB connector

3. (3a-3c) Interface connectors to reader PCB

4. UART connector

5. C2 programming interface for boot loader

6. Indicator LED

1 2

3a

3b

3c 4 5

6





Figure 4: Pico Reader System

The PICO Reader comprises of two PCBs which are stacked on top of each other. On the bottom

side is the controller PCB and on top is the reader PCB. The two PCBs are connected through 3 pin

header connectors with 5 contacts each.

The UHF RFID reader system is connected to the host computer via USB interface that also provides

the power supply for the reader system. The AS399x is supplied with 5V and internally generates

3.3V which in turn supply the MCU.

While the MCU uses its internal clock a 20 MHz crystal oscillator provides the clock for the AS399x

from which all the internal timers are derived.

Since the internal power amplifier (PA) is used the high power Tx ports (RFOUTN, RFOUTP) are

connected. The Tx ports for the external PA are not used and are therefore left open.

The output stage of the internal PA is supplied by the VDD_RF through RF-chokes.

Since the output impedance of the internal PA is not 50 ohm a matching network is needed in order

to transform from the differential output to single ended signals using a 1:1 balun.

After the balun the Tx signal is fed to a directional 10-dB coupler which includes a low pass filter. The

input-coupled pin of the coupler (pin 5) is connected to a 51 resistor in order to minimize reflections

at this pin. The output of the directional coupler is connected to the Tx/Rx antenna port – a U.FL

connector.

The RX signal is coupled with 10 dB of loss to pin 1 of the coupler and then fed to the single-ended

receiver input of AS399x

The communication interface between AS399x and the MCU is SPI which is defined by hardwiring

IO1 to VDD and IO0 to GND.





Pin IO7 acts as MOSI, IO6 is the MISO pin and IO4 is slave select (SS). For a detailed description of

the SPI communication please refer to the datasheet of AS399x. Optionally an UART interface is

available through firmware re-programming an accessible by two pin header on the controller board.

An alternative 5V supply is necessary in this case.





5 Schematics and Layouts

5.1 Schematics

5.1.1 Controller Schematic

Figure 5: Controller Schematic

5.1.2 Reader Schematic

Figure 6: Reader Schematic









5.2 Layouts

5.2.1 Controller PCB Layout

Table 1: Controller PCB Layout

Top Layer Bottom Layer

Top Overlay & Assembly Bottom Overlay





5.2.2 Reader PCB Layout

Table 2: Reader PCB Layout

Top Layer Bottom Layer

Top Overlay Bottom Overlay





6 Impedance Matched Tracks

The reader system is designed for 50 Ohm. Therefore the single ended RF- tracks need to be

matched to the impedance of 50 ohm in order to keep reflections and losses low. The single ended

RF-tracks are designed as coplanar wave guides. The picture below outlines all impedance matched

tracks:

Figure 7: Impedance matched tracks

Note: due to the short length of the differential lines the impedance was not matched.





6.1 Track Impedance Calculation

Figure 8: 50 ohm track - Impedance Calculation

6.2 Reader PCB Stack Up

Figure 9: Reader PCB Layer stack





7 Bill of Materials

7.1 Controller BOM

Table 2: Controller BOM

Designator Comment Component_Description Manufacturer Manufacturer Part Number

C1 10uF MULTICOMP - MCCA000517 - MLCC, 0603, X5R, 6.3V, 10UF

MULTICOMP MCCA000517

C2, C3, C5 100nF MULTICOMP - MCCA000051 - MLCC, 0402, Y5V, 16V, 100NF

MULTICOMP MCCA000051

C4 1uF MULTICOMP - MC0402X105K6R3CT - CAPACITOR CERAMIC 1UF, 6.3V, X5R, 0402

MULTICOMP MC0402X105K6R3CT

D1 LED2 LED GREEN 0.2MM 13MCD 0402 SMD

Rohm Semiconductor

SML-P12PTT86

P1 Header 3 DNP FISCHER ELEKTRONIK - SL1.025.36Z - HEADER, PIN, 2.54MM, 36WAY

FISCHER ELEKTRONIK

SL1.025.36Z

P2, P3, P4 Header 5 - 1.27mm CONN HEADER .050" 5POS PCB GOLD

Sullins Connector Solutions

LPPB051NFFN-RC

P5 UART

R1, R2 Res3 RES 1.0K OHM 1/10W 5% 0402 SMD

Panasonic - ECG

ERJ-2GEJ102X

R3 560R RES 560 OHM 1/16W 1% 0402 SMD

Yageo RC0402FR-07560RL

U1 IC 8051 MCU FLASH 64K 48TQFP

Silicon Laboratories Inc

C8051F340-GQ

U2 USB_B_MINI_Socket_SMD_02

CONN RECEPT MINIUSB R/A 5POS SMD

Molex Inc 54819-0572





7.2 Reader BOM

Table 3: Reader BOM

Designator

Comment Component_Description Manufacturer Manufacturer Part Number

Quantity

C1, C5, C13, C15, C17, C19, C26, C29, C33, C43, C45, C47

2.2uF CAP CER 2.2UF 4.0V X5R 20% 0402

TDK Corporation C1005X5R0G225M 12

C2, C7, C12, C14, C16, C18, C27, C28, C32, C34, C37, C39, C40, C41, C42, C46

10nF MULTICOMP - MCCA000076 - MLCC 0402, X7R, 25V, 10NF

MULTICOMP MCCA000076 16

C3, C4 10pF MURATA - GRM1555C1H100JZ01D - CAPACITOR CERAMIC 10PF 50V, C0G, 0402

MURATA GRM1555C1H100JZ01D

2

C6, C11 12pF CAP CER 12PF 50V 5% NP0 0603

Murata Electronics North America

GRM1885C1H120JA01D

2

C8, C20 4p7F Multilayer Ceramic Capacitors (MLCC) - SMD/SMT 0402 4.7pF 50volt C0G +/-0.25pF

Murata GRM1555C1H4R7CZ01B

2

C9, C10 47pF Multilayer Ceramic Capacitors (MLCC) - SMD/SMT 0402 47pF 50volts C0G 5%

Murata GRM1555C1H470JA01D

2

C21 110pF MULTICOMP - MCCA000117 - MLCC, 0402, NP0, 50V, 110PF


C22 100pF CAP CER 100PF 50V 5% C0G 0402

Murata Electronics North America

GRM1555C1H101JZ01D

1

C24 3.3nF MULTICOMP - MCCA000142 - MLCC 0402, X7R, 50V, 3.3NF


C25, C50 220pF MULTICOMP - MCCA000056 - MLCC 0402, X7R, 25V, 220PF, MULTICOMP - MCCA000056 - MLCC, 0402, X7R, 25V, 220PF


C35, C38 10uF MULTICOMP - MCCA000517 - MLCC 0603, X5R, 6.3V, 10UF


C44 100nF MULTICOMP - MCCA000051 - MLCC 0402, Y5V, 16V, 100NF


L1, L2 39nH MURATA - LQW15AN39NG00D - SPULE, 0402, 39NH

MURATA LQW15AN39NG00D 2

L3, L4 3n9H MURATA - LQW15AN3N9B00D - SPULE, 0402, 3.9NH

MURATA LQW15AN3N9B00D 2

P2, P7, P8

Header 5 - 1.27mm

CONN HEADER .050" 5POS PCB GOLD

Sullins Connector Solutions

GRPB051VWVN-RC 3

P4 U FL Socket - Surface Mount

CONN UMC JACK STR 50 OHM SMD

Hirose Electric Co Ltd

U.FL-R-SMT-1(10) 1

R1 10k RES 10K OHM 1/10W 5% 0402 SMD

Panasonic - ECG ERJ-2GEJ103X 1

R2 56k RES 56K OHM 1/10W 5% 0402 SMD


R3 27k RES 27K OHM 1/10W 5% 0402 SMD


R4 51R RES 51.0 OHM 1/10W 1% 0402 SMD

Panasonic - ECG ERJ-2RKF51R0X 1





R5 51R DNP RES 51.0 OHM 1/10W 1% 0402 SMD

Panasonic - ECG ERJ-2RKF51R0X 1

T1 Balun - JTI - 1:1 BALUN - 0900BL15C050

BALUN GSM/DCS/PCS/CDMA 900MHZ

Johanson Technology Inc

0900BL15C050E 1

T2 Coupler - JTI - 0910CF15B0100

DIR COUPLER W/FILTER 910MHZ

Johanson Technology Inc

0910CF15B0100E 1

U1 AS399x Austriamicrosystems AG

1

Y1 XTAL CRYSTAL 20MHZ 7.2PF SMD

NDK NX3225SA-20.000000MHZ-B2

1





8 Contact Information

Buy our products or get free samples online at:

www.ams.com/ICdirect

Technical Support is available at:

www.ams.com/Technical-Support

Provide feedback about this document at:

www.ams.com/Document-Feedback

For further information and requests, e-mail us at:

[email protected]

For sales offices, distributors and representatives, please visit:

www.ams.com/contact

Headquarters

ams AG

Tobelbaderstrasse 30

8141 Unterpremstaetten

Austria, Europe

Tel: +43 (0) 3136 500 0

Website: www.ams.com


http://www.ams.com/ICdirect

http://www.ams.com/Technical-Support


mailto:[email protected]

http://www.ams.com/contact




9 Copyrights & Disclaimer

Copyright ams AG, Tobelbader Strasse 30, 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.

Information in this document is believed to be accurate and reliable. However, ams AG does not

give any representations or warranties, expressed or implied, as to the accuracy or completeness of

such information and shall have no liability for the consequences of use of such information.

Applications that are described herein are for illustrative purposes only. ams AG makes no

representation or warranty that such applications will be appropriate for the specified use without

further testing or modification. ams AG takes no responsibility for the design, operation and testing

of the applications and end-products as well as assistance with the applications or end-product

designs when using ams AG products. ams AG is not liable for the suitability and fit of ams AG

products in applications and end-products planned.

ams AG shall not be liable to recipient or any third party for any damages, including but not limited

to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect,

special, incidental or consequential damages, of any kind, in connection with or arising out of the

furnishing, performance or use of the technical data or applications described herein. No obligation

or liability to recipient or any third party shall arise or flow out of ams AG rendering of technical or

other services.

ams AG reserves the right to change information in this document at any time and without notice.





10 Revision Information

Changes from 1-00 (2013-Jul-16) to current revision 1-01 (2014-Jul-24) Page

Update to corporate format 1-19

Note: Page numbers for the previous version may differ from page numbers in the current revision.


Documents

AS399x UHF Pico Reader - Digi-Key Notes/austriamicrosystems... · [v1-00] 2014-Jul-24 Document Feedback AS399x UHF Pico Reader ... o Between the Controller and the AS399x is SPI via