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Download QRZ-3100A-PA ZigBee Transceiver User Manual
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QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE QRZ-3100-PA ZigBee Transceiver Module User Manual Version 0.9 The content of this technical information is subject to change without notice. Please contact QuadRep for further information. All rights strictly reserved. Any portion of this paper shall not be reproduced, copied, or transformed to any other forms without permission from QuadRep Electronics [T] Ltd. QuadRep Electronics [T] Ltd. 16F-1, No. 75, Hsin Tai Wu Rd, Sec.1, His-Chih, Taipei, Taiwan TEL: +886-2-26989933 FAX: +886-2-26989911 http:// www.quadrep.com.tw http:// www.quadrep.com.cn Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 1/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE Revision History Version V0.1 V0.2 V0.3 V0.4 V0.5 V0.6 V0.7 V0.8 V0.9 Description First draft version Change TX / RX direction in drawing (page 5) Add application board reference design (page 13-15) Add PCBA picture and manual Index Change circuit diagram (page 12) Modify module mechanical drawing(page 8) Add I/O pin electrical specifications (page 11) Change feature (page 5) Remove QRZ-1100-PA description Editor Liwei Chour Liwei Chour Jess Liu Jess Liu Jess Liu Jess Liu Ted Cheng Liwei Chour Liwei Chour Date 2007/10/23 2007/11/23 2007/12/17 2008/3/3 2008/3/20 2008/4/22 2008/6/16 2009/4/27 2010/4/14 DISCLAIMER ALTHOUGH TO THE BEST KNOWLEDGE OF THE QuadRep ELECTRONIC CORPORATION (QUADREP) THIS DOCUMENT IS ADEQUATE FOR ITS INTENDED PURPOSES, QUADREP MAKES NO WARRANTY OF ANY KIND WITH REGARD TO ITS COMPLETENESS AND ACCURACY. QUADREP EXPRESSLY DISCLAIMS ANY AND ALL OTHER WARRANTIES, EXPRESS, IMPLIED, OR STATUTORY INCLUDING WITHOUT LIMITATION WARRANTIES OF TITLE, MERCHANTABILITY, NON-INFRINGENT, AND FITNESS FOR A PARTICULAR PURPOSE, WHETHER ARISING IN LAW, CUSTOM, CONDUCT OR OTHERWISE. Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 2/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE TABLE OF CONTENTS 1 GENERAL INFORMATION................................................................4 2 BLOCK DIAGRAM ................................................................................5 3 PCBA PICTURES AND MECHANICAL DRAWING.......................6 4 POWER SAVING MODES ..................................................................8 5 CONNECTORS PIN CONFIGURATION..........................................9 6 ELECTRICAL SPECIFICATIONS....................................................10 7 CIRCUIT DIAGRAM ..........................................................................11 8 BILL OF MATERIAL..........................................................................12 9 APPLICATION CIRCUIT DIAGRAM .............................................14 10 DESIGN GUIDE TO AVOID RF INTERFERENCE........................15 11 UART COMMANDS............................................................................18 12 RF PERFORMANCE TEST DATA ...................................................19 13 REFERENCE REFLOW TEMPETURE CURVE............................20 14 REFERENCE DOCUMENTS.............................................................24 Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 3/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE Revised Date: Jun. 16, 2008 1. GENERAL INFORMATION The QRZ-3100-PA is a miniature 2.4 GHz Direct Sequence Spread Spectrum ZigBee transceiver. It includes all RF hardware and a micro-controller to manage the communications link. The microcontroller manages all communications task including configuration, data packaging, and clear channel selection. The result is a complete wireless data communications solution. The QRZ-3100-PA package is unique because of its small form factor (32 x 23 mm2), It has an onboard chip antenna and the availability of external dipole antenna I-PEX connector. No competitive products can offer a solution as flexible, convenient, and easy to integrate, There are two QRZ-3100 serial models; the QRZ-3100 with the on-board chip antenna and dipole antenna I-PEX connector, the QRZ-3100-PA with power amplifier, low noise amplifier, on-board chip antenna and dipole antenna I-PEX connector. The power amplifier enhances the transmission power and low noise amplifier increases receiving signal sensitivity. The power amplifier, low noise amplifier and dipole antenna improve range while the QRZ-3100 lowers system cost and simplifies integration. Models • QRZ-3100-PA: Includes PA/LNA, On-board chip Antenna Connector, MCU is Megawin MPC82X54AT • QRZ-3100-PAE: Includes PA/LNA, Dipole Antenna Connector, MCU is Megawin MPC82X54AT Features • 32 x 23 mm2 PCBA package with 2 connectors • Utilizes globally available 2.4 GHz ISM band • Control and Configuration with UART commands. • Programmable Transmit Power Output, max. 9 dBm • Complete IEEE 802.15.4 spec compliant • Typical Receiver Sensitivity –101 dBm • Typical Throughput rate 250,000 bps • Multiple Low Power Operating modes • Meet RoHS Requirement Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 4/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 2. BLOCK DIAGRAM Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 5/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 3. PCBA PICTURES AND MECHANICAL DRAWING Chip on Antenna UZ2400 UZ2400 MPC82L54AT UP2268 Figure 1. QRZ-3100-PA PCBA Front View UZ2400 UZ2400 I-Pex MPC82L54AT UP2268 Figure 2. QRZ-3100-PAE PCBA Front View Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 6/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE QRZ-3100-PA ZigBee Transceiver Module Mechanical Drawing 23mm AT5020 7.0mm 1.3mm 2.0mm 0.76mm 32mm J1 1.0mm C2CK _1 C2D VDD _2 3 0.63mm J2 1 GPIO3 4 2 GPIO4 5 3 GPIO5 RX1 1.27mm GPIO1 6 4 GPIO6 7 5 GPIO7 GPIO2 2.0mm 8 6 GPIO8 TX1 0.55mm 2.0mm 4.0mm 1.0mm 1.55mm 2.7mm Note : J1, J2 are SMD type with stamp holes Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 7/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 4. POWER SAVING MODES The QRZ-3100-PA includes several low power operating modes to permit the most efficient use of the available power. Below are descriptions of the available selections. ACTIVE: In Active Mode, all QRZ-3100-PA circuits are powered and available for immediate action. This includes the RF receiver which actively monitors the air for an incoming communications request. Two sub-modes are classified as TX-ACTIVE and RX-ACTIVE. The current consumption of TX-ACTIVE is 35 mA while RX-ACTIVE is 34 mA. SLEEP(Internal wakeup): In this mode, MCU circuits stop. The RF chip circuits work and start counting. When time up, the RF chip wakes up automatically. Then the RF chip wakes MCU up using interrupt. Current draw in Standby Mode is less than 110 uA. SLEEP(External wakeup): In this mode, MCU and RF chip circuits stop. Users can use intreeupt to wake MCU up. When MCU wake up, it use the COMMAND to wake RF chip up. Current draw in Standby Mode is less than 110 uA. Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 8/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 5. CONNECTORS PIN CONFIGURATION QRZ-3100-PA uses Megawin MPC82X54AT as MCU. It is an 8051 base MCU and reserves 10 GPIO pins for external controlling by application. Each pin can be a general I/O pin and programmed it by user directly. Furthermore, most of these pins can be used as special purpose function. Thereof TX, RX pins can be programmed as UART for data communication. For example, user is easy to connect these pins with RS485 transceivers such as 75176, MAX485, or programs to a 10-bit ADC, or PCA. J1 Pin Configuration Signal Pin Description C2CK 1 (Reserved) C2D 2 (Reserved) VCC 3 3.3 Volt power for the QRZ-3100A-PA TX 4 GPIO, also used as UART TX, transmits data from QRZ-3100A to UART GND 5 Common voltage reference for the QRZ-3100A-PA RX 6 GPIO, also used as UART RX, receives data from UART to QRZ-3100A. GPIO1 7 GPIO port 3.3, may be programmed as either a digital input or digital output. It also can be programmed as external interrupt GPIO2 8 GPIO port 3.4, may be programmed as either a digital input or digital output. It also can be programmed as external clock input to PCA as alternative clock input to timer-0 J2 Pin Configuration Signal Pin Description GPIO3 1 GPIO port 3.5, may be programmed as either a digital input or digital output. It also can be programmed as external clock input to PCA as alternative clock input to timer-1 GPIO4 2 GPIO port 3.7, may be programmed as either a digital input or digital output. It also can be programmed as external clock input to PCA GPIO5 3 GPIO port 1.0, may be programmed as either a digital input or digital output. It also can be programmed as analog to digital converter (ADC0) GPIO6 4 GPIO port 1.1, may be programmed as either a digital input or digital output. It also can be programmed as analog to digital converter (ADC1) GPIO7 5 GPIO port 1.2, may be programmed as either a digital input or digital output. It also can be programmed as analog to digital converter (ADC2) GPIO8 6 GPIO port 1.3, may be programmed as either a digital input or digital output. It also can be programmed as analog to digital converter (ADC3) Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 9/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 6. ELECTRICAL SPECIFICATIONS Absolute Maximum Rating VCC 3.6 V Storage temperature -40°C to +120°C Operating temperature Range -30°C to +80°C WARNING: Exceeding any of these ratings will void the warranty and may damage the device Parameters Supply Voltage for RF, analog and digital circuits Digital I/O Pin Input High Voltage Digital I/O Pin Input Low Voltage Analog Input Pin Input Voltage I/O Pin Output High Current I/O Pin Output Low Current I/O Pin Input High Current I/O Pin Input Low Current Current Consumption ACTIVE TX Mode @ 12 dBm ACTIVE RX Mode SLEEP(Internal wakeup) SLEEP(external wakeup) Output Power Wireless Receive Sensitivity Selectable Channels Frequency Band Antenna Output Impedance Confidential Min 3 2.0 Typ 3.3 Max 3.6 0.8 0 4 8 3.3 8 14 0 0 V mA mA uA uA 10 10 35 34 110 110 9 -101 16 2.400 Doc. #: AN-QRZ-3100-PA<Rev. 0.9> 2.4835 50 Units V V V mA mA uA uA dBm dBm channel GHz Ohms Page 10/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 7. CIRCUIT DIAGRAM +VCC C2 330PF AGND TXEN VCC C3 0.1UF AGND 27pF C1 R1 R XEN C16 2 +VCC 1nH L4 5.1nH 0.5PF 1PF L5 9.1nH L6 5.1nH C19 AGND VCC 0. 5PF TXEN 2 AGND 0R +VCCEN C23 15PF AGND VCC *3 VDD_RF1 RF_P RF_N VDD_RF2 VDD_GR GND_GR GPIO0 GPIO1 GPIO5 GPIO4 C60 33pF RX_QP RX_IP XTAL32_P XTAL32_N CLK_OUT SCAN_M SCAN_EN SPI/I2C GND_D VDD_D 30 29 28 27 26 25 24 23 22 21 R3 10MR VCC X2 32768Hz C64 33pF C63 VCC 10nF AGND 1 10nH 1 1 11 12 13 14 15 16 17 18 19 20 L7 2.4nH RXEN 1K C22 33PF C21 0.1UF 1 2 3 4 5 6 7 8 9 10 1 AGND +VCC C55 1nF R53 10nF 40 39 38 37 36 35 34 33 32 31 41 C15 GND C14 RF TXEN L10 2 C57 47pF LOOP_C VDD_VCO NC VDD_CP GND_PLL VDD_PLL XTAL_P XTAL_N VDD_A VDD_BG RF2 VC2 GND RFC RF1 VC1 HWS408_SOT363 2 6 5 4 R2 C20 1PF C58 180pF 1 C18 39PF U2 2 1 2 3 TXout AGND AGND C48 2 17 LNA_out NC PA_in PA_VL0 8 7 6 5 1 AGND C12 15PF C13 47PF RXin 1 2 3 4 2 GPIO2 GPIO3 #RESET MSEL WAKE INT SO SI SCLK SEN U1 UP2268_QFN16 R XEN S C8 27pF 1 I-PEX AGND AGND G G VCC 1 GND GND 15PF 20MHz S C53 GND 13 14 15 16 L9 1.8pF 3 RF_LNA PA_VL1 RF_ANT LNA_VL0 4 1uF RF_PA PA_Vcc PA_Vcc PA_Vb C52 1.5pF 1 RF 2 0R 2 C17 U3 4.3nH 12 11 10 9 LAN_in LNA_VL1 LNA_Vb LNA_Vcc1 1 R23 C7 0.1UF VCC C5 47PF AGND AT5020 C51 C6 330PF L3 3. 9nH C9 47PF AGND 10nF C4 10NF 2 L1 4. 7nH 1 1 X1 3 2 1K5 L2 C56 1nF AGND C26 R13 10KR +VCC L8 1 RXEN UZ_Reset WAKE UZ_Int SPI_SO SPI_SI SPI_SCLK SPI_SEN 2 R4 10KR 3PF AGND 1nH C27 330PF C25 0. 5PF C28 0. 1UF AGND AGND R55 0R R57 0R VSS VCC VDD R54 NC *1 VCC *2 VSS 1 2 C44 1uF VCC U8 3 VINVOUT 2 4 1uF C45 C11 470nF J1 +VCCEN 3 VINVOUT R17 10K 5 EN NC 4 1MR R15 1KR R16 1KR 1uF C24 470nF RX1 TX1 3 10nF 1 C46 27pF X3 2 12MHz C47 GPIO1 GPIO2 GPIO3 27pF R18 560R INT 4 5 6 7 8 9 10 RST RXD TXD VCC SCLK MI SO MOSI SS XTAL2 XTAL1 P1.3 INT0/P3.2P1.2 INT1/P3.3P1.1 T0/ P3.4 P1.0 T1/ P3.5 GND P3.7 MPC82E54A 20 19 18 17 16 R19 560R R20 560R GPIO8 GPIO7 GPIO6 GPIO5 15 14 13 12 TX1 . RX1 U9 2 3 C10 4 10nF . VDD R11 1 GND RT9193-33PB C2CK C2D VDD C42 +VCC U6 1 C43 NC RT9193-33PB VDD VDD VCC 5 GND EN +VCCEN +VCCC R58 NC VDD TX1 RX1 GPIO1 GPIO2 1 2 3 4 5 6 7 8 J2 GPIO3 GPIO4 GPIO5 GPIO6 GPIO7 GPIO8 1 2 3 4 5 6 SPI_SCLK SPI_SO SPI_SI SPI_SEN R21 560R R22 560R D1 LED GPIO4 11 R12 330R Note *1 For DC_5V *2 For RF_Power *3 For Sleep_Mode Title Size: QRZ-3100-PA A4 »OÆW¼sµn¹q¤l Date:2008.3.20 File:Y:\RD Document\ZigBee\Internal\Product --- Module Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 11/20 QuadRep Electronics [T] Ltd. 8. BILL OF MATERIAL Item Quantity Reference 1 1 A1 2 1 C4 3 1 C7 4 1 C9 5 2 C10,C12 6 3 C11,C18,C20 7 1 C13 8 1 C14 9 2 C16,C15 10 1 C17 11 2 C21,C54 12 4 C22,C24,C25,C26 13 1 C23 14 2 C27,C29 15 2 C31,C28 16 1 C30 17 1 C32 18 1 C33 19 2 C37,C43 20 1 C38 21 4 C39,C52,C58,C63 22 2 C57,C40 23 1 C48 24 1 C53 25 2 C60,C64 26 3 C65,C66,C67 27 1 C68 28 2 C69,C70 29 1 D1 30 1 J1 31 1 J2 32 1 L1 33 1 L2 34 2 L5,L3 35 1 L4 36 1 L6 37 1 L7 38 1 RFIN_g1 Confidential Product #: QRZ-3100-PA,QRZ-3100-PAE Part AT5020 100pF NC 10pF NC 330pF 33pF 100nF 1.5pF 1.8pF 27pF 7pF 3nH 20pF 470nF 20pF 10nF 3.3pF 0.5pF 10pF 10nF 47pF 180pF 1uF 33pF 1uF 10nF 27pF LED CON5 CON10A 1.8nH 4.7nH 5.1nH 9.1nH 2nH 33nH I-PEX Antenna Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Description LCC8 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0805 0402 0402 0805 HD_1.27 HD_1.27 0402 0402 0402 0402 0402 0402 Page 12/20 QuadRep Electronics [T] Ltd. 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 59 61 62 63 Confidential 2 1 1 1 2 1 1 1 2 2 1 1 4 1 1 1 1 1 1 1 1 1 R2,R1 R3 R4 R5 R6,R17 R7 R8 R10 R15,R11 R12,R13 R14 R16 R18,R19,R20,R21 TP1 U1 U3 U4 U6 U8,U10 X1 X2 X3 Product #: QRZ-3100-PA,QRZ-3100-PAE 180R 30R 10KR 10MR 0R 160R 24KR 0R 10KR 1KR 220R 4.7KR 560R I-PEX_ANTENNA UZ2400 MPC82X54AT UP2268 HWS408 RT9193-33PB 20MHz 32768Hz 11.0592MHz Doc. #: AN-QRZ-3100-PA<Rev. 0.9> 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 0402 TP24S QFP40-0.5 SOP20-7.5_1.27 2_2_8LEAD AS179 SOT-23-5 CX_101F OSC2 XTAL-5X3.2-4P_S Page 13/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 9. APPLICATION CIRCUIT DIAGRAM SIPEX SP3232EBCP APPLICATION CIRCUIT QRZ-3100A-PA to RS232 VCC QRZ3100A -PA VCC RX_IN 13 8 11 10 TX1 RX1 C2 0.1uF 1 3 4 5 2 6 VCC C3 0.1uF C4 0.1uF C5 0.1uF C1 10uF _ R1IN R2IN T1IN T2IN 16 VCC 12 9 14 7 R1OUT R2OUT T1OUT T2OUT C+ C1C2+ C2V+ V- 1 6 2 7 3 8 4 9 5 RX1 TX_OUT 15 GND TX_OUT RX_IN DB-9pin SP3232EBCP PROLIFIC PL2303 APPLICATION CIRCUIT QRZ-3100A-PA to USB VCC QRZ3100APA U5 PL2303 VCC RX1 TX1 VCC R5 4.7K C33 0.1uF 1 2 3 4 5 6 7 8 9 10 11 12 13 14 TXD DIR_N RST_N VDD_232 RXD RI_N GND VDD DSR_N DCD_N CTS_N SHTD# EE_CLK EE_DATA 28 27 26 25 24 23 22 21 20 19 18 17 16 15 OSC2 OSC1 PLL_TEST GND_PLL VDD_PLL LD_MODE TRI_STATE GND VDD RESET GND_3V3 VDD_3V3 DM DP VDD VCC R6 R7 D2 1N4148 P1 1 2 3 4 5 6 +5V DM0 DP0 GND SHELL 1 C31 0.1uF C32 DM0 27DP0 27 0.1uF VCC VDD 2 C36 4.7nF 250 VAC USB TY PE A CONN USB-A-90_D/UAR-1 R8 C34 C35 NC NC 1.5K 16V R9 1M E_GND Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 14/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 10. DESIGN GUIDE TO AVOID RF INTERFERENCE When RF module put on an application board(mother board), to minimize the RF signal interference, the best way is to define an isolation area. This area should have no any trace or grounding pad. Here are some layout suggestions for mother board. Suggestion 1: Place RF board aside mother board. (Let antenna part outside mother board is better) Make sure no trace and grounding pad under the must isolate area. Please see the drawing as below. Must Isolate Area Prefer Isolate Area Module Board Via Mother Board Antenna Suggestion 2: Place RF board at the corner of mother board. Make sure no trace and grounding pad under the must isolate area. Please see the drawing as below. Must Isolate Area Prefer Isolate Area RF Module Board Via Customer's Mother Board Antenna Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 15/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE Suggestion 3: If you couldn’t put RF board at one side or at the corner of mother board. You must make sure no circuit trace and grounding pad under the must isolate area, and at least reserve extra 3 mm space as safety area. Please see the drawing as below. Must Isolate Area Prefer Isolate Area RF Module Board Via Customer's Mother Board Antenna For all of above suggestions, try to extend isolation area from must area to prefer area. Please see the drawing as below. The more isolation area, the better RF performance。 Must Isolate Area Prefer Isolate Area RF Module Board Via Customer's Mother Board Antenna Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 16/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE Must Isolate Area Prefer Isolate Area RF Module Board Via Customer's Mother Board Antenna Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 17/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 11.RF PERFORMANCE TEST DATA Return Loss: -14.2dB Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 18/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 12. REFERENCE REFLOW TEMPETURE CURVE Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 19/20 QuadRep Electronics [T] Ltd. Product #: QRZ-3100-PA,QRZ-3100-PAE 13. Reference Documents 13.1 UBEC UZ2400 datasheet 13.2 UBEC UP2268 datasheet 13.3 ACX AT5020 datasheet Copyright, QuadRep Electronics © 2007 While QuadRep Electronics, Inc. has made every effort to ensure that the information presented here is accurate, QuadRep will not be liable for any damages arising from errors or omission of fact. QuadRep reserves the right to modify specifications and/or prices without notice. Products mentioned herein are used for identification purposes only and may be trademarks and/or registered trademarks of their respective companies. QuadRep Electronics [T] Ltd. 16F-1, No. 75, Hsin Tai Wu Rd, Sec.1, His-Chih, Taipei, Taiwan TEL: +886-2-26989933 FAX: +886-2-26989911 http:// www.quadrep.com.tw http:// www.quadrep.com.cn Confidential Doc. #: AN-QRZ-3100-PA<Rev. 0.9> Page 20/20
