High Performance ISM Band OOK/FSK Transmitter IC ADF7901 FEATURES GENERAL DESCRIPTION Single-chip, low power UHF transmitter The ADF7901 is a low power OOK/FSK UHF transmitter 369.5 MHz to 395.9 MHz frequency operation using designed for use in RF remote control devices. It is capable of fractional-N PLL and fully integrated VCO frequency shift keying (FSK) modulation on eight different 3.0 V supply voltage channels, selectable by three external control lines. OOK Data rates up to 50 kbps supported modulation is performed by modulating the PA control line. Low current consumption 26 mA at 12 dBm output at 384 MHz The on-chip VCO operates at 2 the output frequency. The Power-down mode (<1 A) division by 2 at the output of the VCO reduces the amount of 24-lead TSSOP PA feedthrough. As a result, OOK modulation depths of greater than 50 dB are easily achievable. The FSK ADJ and ASK ADJ resistors can be adjusted in the system to optimize output power for each modulation scheme. An additional 1.5 dB of output power is provided for the lower bank of channels to adjust for antenna performance. The CE line allows the transmitter to be powered down completely. In this mode, the leakage current is typically 0.1 A. FUNCTIONAL BLOCK DIAGRAM C REG2 PA EN C VCO OSC1 OSC2 V DD VCO RF OUT PA DV DD R = 1 RF GND PDF CHARGE PUMP C LDO REG1 REGULATOR 1 FRACTIONAL N LDO C REG2 REGULATOR TXDATA - FSK 2 CHANNEL SELECT R SET OOK SEL CE D FSK1 FSK2 FSK3 GND RSET FSK RSET OOK Figure 1. Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 2006 Analog Devices, Inc. All rights reserved. 05349-001ADF7901 TABLE OF CONTENTS Features .............................................................................................. 1 Channel Frequencies.....................................................................9 General Description ......................................................................... 1 Layout Guidelines....................................................................... 10 Functional Block Diagram .............................................................. 1 Decoupling.............................................................................. 10 Specifications..................................................................................... 3 Regulator Stability.................................................................. 10 Absolute Maximum Ratings............................................................ 5 Grounding............................................................................... 10 ESD Caution.................................................................................. 5 Supply ...................................................................................... 10 Pin Configuration and Function Descriptions............................. 6 Digital Lines............................................................................ 10 Typical Performance Characteristics ............................................. 8 Outline Dimensions....................................................................... 11 Circuit Description........................................................................... 9 Ordering Guide .......................................................................... 11 Loop Filter ..................................................................................... 9 REVISION HISTORY 3/06Rev. 0 to Rev. A Added Crystal ESR Parameter ........................................................ 4 Change to Figure 8 ......................................................................... 10 Updated Outline Dimensions ....................................................... 11 Changes to Ordering Guide .......................................................... 11 3/05Revision 0: Initial Version Rev. A Page 2 of 12