EVB7107 315/433MHz Transmitter Evaluation Board Description Features ! Fully integrated, PLL-stabilized VCO ! Adjustable equivalent radiated power (ERP) ! Frequency range from 310 MHz to 440 MHz range from -25 dBm to -10 dBm ! FSK through crystal pulling allows modulation ! Adjustable current consumption from from DC to 40 kbit/s 4.8 mA to 11.5 mA ! High FSK deviation possible for wideband data ! FSK deviation and center frequency transmission independently adjustable ! ASK achieved by on/off keying of internal ! Differential output well-suited for loop antenna power amplifier ! External clock available for µC drive, ! FM possible with external varactor down to 1.9 V supply ! Wide power supply range from 2.2 V to 5.5 V ! ”Clock only” mode ! High over-all frequency accuracy ! Conforms to EN 300 220 and similar standards ! Very low standby current Ordering Information Part No. EVB7107-433-FSK EVB7107-315-FSK EVB7107-433-ASK EVB7107-315-ASK Application Examples Evaluation Board Example ! Keyless car and central locking ! Low-power telemetry ! Alarm and security systems ! General digital data transmission ! General analog audio signal transmission General Description The TH7107 antenna board is designed to optimally match the differential power amplifier output to a loop antenna. The TH7107 can be populated either for FSK, ASK or FM transmission. The default population is for FSK or ASK transmission. Adding a varactor diode can easily be done in order to modify the circuit for analog FM. The evaluation board contains a differential-drive loop antenna printed on the PCB (Printed Circuit Board). The size of the loop antenna is matched to the resonant frequency. 390120710701 Page 1 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description Document Content 1 Theory of Operation...................................................................................................3 1.1 General........................................................................................................................... 3 1.2 Block Diagram ................................................................................................................ 3 2 Functional Description ..............................................................................................4 2.1 FSK Modulation .............................................................................................................. 4 2.2 Frequency Modulation .................................................................................................... 4 2.3 ASK Modulation .............................................................................................................. 4 2.4 Mode Control Logic......................................................................................................... 4 3 Circuit Diagram ..........................................................................................................5 3.1 PCB Top View ................................................................................................................ 6 3.2 Board Connection ........................................................................................................... 6 3.3 Board Component Values............................................................................................... 7 4 Package Information..................................................................................................8 5 Disclaimer.................................................................................................................10 390120710701 Page 2 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description 1 Theory of Operation 1.1 General As depicted in Fig.1, the TH71071 transmitter consists of a fully integrated voltage-controlled oscillator (VCO), a divide-by-32 divider (div32), a phase-frequency detector (PFD) and a charge pump. An external loop filter at pin LF determines the dynamic behaviour of the PLL and suppresses reference spurious signals. The VCO’s output signal feeds the power amplifier (PA). RF signal power P can be adjusted in six steps o from P = –12 dBm to +2 dBm either by changing the value of resistor R1 or by varying the voltage V at pin o PS PS/DATA. The open-collector differential output (OUT1, OUT2) can be used to either directly drive a loop antenna or to be converted to a single-ended impedance by means of a balanced-to-unbalanced (balun) transformer. For maximum available output power, the differential output should be matched to a load of about 1 kΩ. Bandgap biasing ensures stable operation of the IC at a power supply range of 2.2 V to 5.5 V. 1.2 Block Diagram RPS VCC 10 VCC 15 PS 9 VEE 14 OUT1 CKOUT 13 antenna div 4 PA or div32 8 balun OUT2 VCC 12 VEE RO1 PFD 11 VCO 5 XTAL ENCK XOSC mode 7 RO2 control charge ENTX 4 CX2 pump 6 CX1 3 DATA 16 1 LF1 LF2 2 SUB CF1 CF2 RF1 Fig. 1: Block diagram with external components 390120710701 Page 3 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description 2 Functional Description 2.1 FSK Modulation A Colpitts crystal oscillator (XOSC) is used as the reference oscillator of a phase-locked loop (PLL) synthesizer. FSK modulation is achieved by pulling the crystal (XTAL) through the data. So a CMOS- compatible data stream applied at input DATA digitally modulates the XOSC. Two external pulling capacitors CX1 and CX2 allow the FSK deviation and center frequency to be adjusted independently. At DATA = LOW CX2 is connected in parallel to CX1 leading to the low-frequency component of the FSK spectrum (f ); min while at DATA = HIGH CX2 is deactivated and the XOSC is set to its high frequency, leading to f . max An external reference signal can be directly AC-coupled to pin RO1. Then the TH7107 is used without an XTAL. The reference signal has to contain the FSK (or FM) and sets the carrier frequency. 2.2 Frequency Modulation For FM operation an external varactor is required. It simply acts as a pulling capacitor connected in series to the crystal. Then the analog modulation signal, applied through a series resistor, directly modulates the XOSC. 2.3 ASK Modulation The TH7107 can be ASK-modulated by applying data directly at pin PS. This turns the PA on and off and therefore leads to an ASK signal at the output. 2.4 Mode Control Logic The mode control logic allows four different modes of operation as listed in the following table. The mode control pins ENCK and ENTX are pulled-down internally. This guarantees that the whole circuit is shut down if these pins are left floating. The clock output CKOUT can be used to drive a µC. This output can be activated by the ENCK pin as required for any specific application. Clock frequency is 1/4 of the reference crystal frequency. ENCK ENTX Mode Description 0 0 all OFF whole circuit in standby 0 1 TX only TX active, no clock available 1 0 clock only TX standby and clock available 1 1 all ON TX active and clock available For more detailed information, please refer to the latest TH7107 data sheet revision. 390120710701 Page 4 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description 3 Circuit Diagram C2 C1 RX L2 L1 C3 C4 RPS RF2 CX2 XTAL RF1 R3 CX3 CX1 CF2 CF1 V1 R1 R2 C5 1 1 2 2 1 2 12 12 3 1 2 390120710701 Page 5 of 10 EVB Description Rev. 008 June/03 1 16 LF1 LF2 2 15 VCC SUB VCC GND 3 14 DATA FSK VEE GND 4 13 RO2 FM/ASK OUT1 GND 12 5 RO1 OUT2 ENTX 6 11 VCC ENTX VEE VCC 7 10 ENCK ENCK VCC GND 8 9 CKOUT CKOUT PS GND EVB7107 315/433MHz Transmitter Evaluation Board Description 3.1 PCB Top View Board layout data in Gerber format is available 433 MHZ C2 C1 L1 L2 C4 RX C3 RPS 16 9 TH7107 1 8 CF1 CF2 CX1 R1 Cx3 V1 XTAL C5 11 1 1 1 1 Board size is 48mm x 48mm 3.2 Board Connection VCC Power supply (2.2 V to 5.5 V) ENCK Mode control pin (see para. 2.4)) FSK Input for FSK data (CMOS) ENTX Mode control pin (see para. 2.4)) FM/ASK Input for FM signal (analog) or ASK data (CMOS) GND Several ground pins CKOUT Clock output (3.4 MHz) 390120710701 Page 6 of 10 EVB Description Rev. 008 June/03 VCC GND FSK R2 GND FM/ASK RF2 RF1 GND CX2 ENTX VCC R3 VCC ENCK GND CKOUT GND Melexis EVB7107 315/433MHz Transmitter Evaluation Board Description 3.3 Board Component Values Value Value Part Size Tolerance Description 315 MHz 433.6 MHz CF1 0805 12 nF 10 nF ±10% loop filter capacitor CF2 0805 15 pF 12 pF loop filter capacitor ±10% CX1 0603 39 pF 39 pF _FSK ±5% XOSC capacitor for FSK (Δf = ±20 kHz) CX1 0603 68 pF 68 pF XOSC capacitor for ASK, trimmed to f _ASK ±5% C XOSC capacitor, only needed for FSK CX2 0603 1 nF 1 nF ±5% XOSC capacitor, only needed for FM CX3 0603 1 nF 1 nF ±10% C1 1206 3.9 pF 3.9 pF antenna resonance capacitor ±2% C2 0805 3.9 pF 2.2 pF antenna resonance capacitor ±2% C3 0603 330 pF 330 pF blocking capacitor ±10% C4 0603 330 pF 330 pF ±10% blocking capacitor C5 1206 220 nF 220 nF blocking capacitor ±20% L1 0603 220 nH 220 nH biasing inductor ±10% L2 0603 220 nH 220 nH biasing inductor ±10% RF1 0805 2.0 kΩ 2.0 kΩ ±10% loop filter resistor RF2 0805 loop filter resistor 4.3 kΩ 4.3 kΩ ±10% RPS 0805 power-select resistor, see data sheet para. 4.6 56 kΩ 56 kΩ ±10% R1 0805 optional pull-up resistor, typically not needed 470 kΩ 470 kΩ ±10% R2 0805 varactor bias resistor, only needed for FM 30 kΩ 30 kΩ ±10% ASK jumper, only needed for ASK R3 0805 0 Ω 0 Ω ±10% RX 0603 damping resistor 4.7 kΩ 4.7 kΩ ±10% V1 SOD323 BB535 varactor diode, only needed for FM XTAL HC49/S 9.8438 MHz 13.5500 MHz crystal, C = 12 pF to 15 pF, C = 7 pF ±30ppm load 0, max fundamental fundamental calibration R = 40 Ω m, max wave wave ±30ppm temp. PCB long side 44 mm 44 mm on FR4 PCB material loop length side length including length of C1 and C2 antenna PCB small side 20 mm 12 mm on FR4 PCB material loop length antenna PCB Line width 2 mm 2 mm on FR4 PCB material loop antenna The listed component values are default values. All values might be changed to fit to any specific application. As for example FSK deviation can be set by varying CX1 and CX2, output power at FSK/FM transmission can be changed through RPS or through RPS and R3 at ASK transmission, respectively. Pads for C1 are for population of a fixed-value capacitor with size 1206 or a to use trimming capacitor either. 390120710701 Page 7 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description 4 Package Information D ZD e 7° 16 1 0.254 L (0.010) DETAIL-A b + 3° 7° DETAIL-A 0.36 x 45° BSC (0.0014x45°) C .10 (.004) Fig. 2: QSOP16 (Quarter size Small Outline Package) all Dimension in mm, coplanarity < 0.1mm D E1 E A A1 A2 e b ZD C L α α α α min 4.80 3.81 5.79 1.35 0.10 1.37 0.20 0.19 0.40 0° 0.635 0.230 max 4.98 3.99 6.20 1.75 0.25 1.50 0.30 0.25 1.27 8° all Dimension in inch, coplanarity < 0.004” min 0.189 0.150 0.228 0.0532 0.0040 0.054 0.008 0.075 0.016 0° 0.025 0.009 max 0.196 0.157 0.244 0.0688 0.0098 0.059 0.012 0.098 0.050 8° 390120710701 Page 8 of 10 EVB Description Rev. 008 June/03 A A2 E1 A1 E EVB7107 315/433MHz Transmitter Evaluation Board Description Your Notes 390120710701 Page 9 of 10 EVB Description Rev. 008 June/03 EVB7107 315/433MHz Transmitter Evaluation Board Description 5 Disclaimer Devices sold by Melexis are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. Melexis makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. Melexis reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with Melexis for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life- support or life-sustaining equipment are specifically not recommended without additional processing by Melexis for each application. The information furnished by Melexis is believed to be correct and accurate. However, Melexis 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, interrupt 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 herein. No obligation or liability to recipient or any third party shall arise or flow out of Melexis’ rendering of technical or other services. © 2002 Melexis NV. All rights reserved. For the latest version of this document. Go to our website at www.melexis.com Or for additional information contact Melexis Direct: Europe and Japan: All other locations: Phone: +32 1367 0495 Phone: +1 603 223 2362 E-mail: sales_europe@melexis.com E-mail: sales_usa@melexis.com QS9000, VDA6.1 and ISO14001 Certified 390120710701 Page 10 of 10 EVB Description Rev. 008 June/03