RF2506 Preliminary 12 VHF/UHF VCO/HIGH-ISOLATION BUFFER AMPLIFIER Typical Applications • Low Voltage • Wireless Local Loop • Wireless LANs • Digital Cordless Phones • IF LO for 2.45GHz ISM Band Systems Product Description The RF2506 is an integrated oscillator and buffer amplifier chain designed to achieve low sensitivity to fluctuations in load impedance and power supply noise, while maintaining superior phase noise performance. The IC offers great flexibility, yet is easy to use. This product was designed for use in applications with low supply voltages. It has a power-down feature and is designed to operate from 10MHz to 1000MHz with the help of an external resonator. Frequency control is achieved with an external varactor diode. The IC’s ease of use, reduced load pulling, small size, and low cost make it an ideal LO (Local Oscillator) for wireless applications in the VHF/UHF range. The RF2506 was designed to operate with the 2.4GHz chipset; specifically with the IF portion of the RF2518 PLL/synthesizer. 0.012 üSi Bi-CMOS GaAs HBT GaAs MESFET SiGe HBT Si CMOS A 0.0256 0.118 + 0.004 sq. 0.034 6° MAX 0° MIN 0.021 + 0.004 Optimum Technology Matching® Applied Si BJT 0.006 + 0.003 0.192 + 0.008 0.006 + 0.002 NOTES: 1. Shaded lead is pin 1. 2. All dimensions are exclusive of flash, protrusions or burrs. 3. Lead coplanarity: 0.002 with respect to datum "A". Package Style: MSOP-8 Features • High-Isolation/Reduced Load Pulling 12 PLLs and VCOs • Low Current Consumption • -7dBm Output Power VCC1 1 8 PD • Digitally Controlled Power Down Mode GND1 2 7 VCC2 • 10MHz to 1GHz Operating Range FDBK 3 6 GND2 • Single 2.7V to 3.6V Supply VTUNE 4 5 RF OUT Ordering Information RF2506 RF2506 PCBA Functional Block Diagram Rev A1 000908 VHF/UHF VCO/High-Isolation Buffer Amplifier Fully Assembled Evaluation Board RF Micro Devices, Inc. 7628 Thorndike Road Greensboro, NC 27409, USA Tel (336) 664 1233 Fax (336) 664 0454 http://www.rfmd.com 12-9 RF2506 Preliminary Absolute Maximum Ratings Parameter Supply Voltage Power Down Voltage (VPD) Operating Ambient Temperature Storage Temperature Parameter Rating Unit -0.5 to +5.8 -0.5 to +5.8 -40 to +85 -55 to +150 VDC VDC °C °C Caution! ESD sensitive device. RF Micro Devices believes the furnished information is correct and accurate at the time of this printing. However, RF Micro Devices reserves the right to make changes to its products without notice. RF Micro Devices does not assume responsibility for the use of the described product(s). Specification Min. Typ. Max. Unit 10 to 1000 MHz Condition Overall Operating Frequency T=25 °C, VCC =2.7V, ZLOAD =50Ω, VPD =2.7V, O/P terminated into LC. Characterized @ 560MHz as per eval board. Data will change depending on frequency of operation and resonant tank network. 560MHz Operation Output Power 2nd Harmonic 3rd Harmonic Load Pulling VCC Pushing Phase Noise -3 -27 -35 50 190 -110 dBm dBc dBc kHzP-P kHz/V dBc -90 dBc -7 -11.5 -15.5 35 160 -107 dBm dBc dBc kHzP-P kHz/V dBc -88 dBc 2.7 to 3.6 VDC 9 mA 560MHz Operation PLLs and VCOs 12 Output Power 2nd Harmonic 3rd Harmonic Load Pulling VCC Pushing Phase Noise Into 1.75 VSWR Load Supply sweep from 2.7V to 3.2V 100kHz Offset. Better phase noise is achievable by increasing the loaded Q of the resonator circuit. 10kHz Offset T=25 °C, VCC =2.7V, ZLOAD =50Ω, VPD =2.7V, O/P terminated in 50Ω. Characterized @ 560MHz as per eval board. Data will change depending on frequency of operation and resonant tank network. Into 1.75 VSWR Load Supply sweep from 2.7V to 3.2V 100kHz Offset. Better phase noise is achievable by increasing the loaded Q of the resonator circuit. 10kHz Offset Power Supply Operating Voltage Supply Current 12-10 At 2.2V and -40°C, output power will be reduced to typically -11dBm. Rev A1 000908 RF2506 Preliminary Pin 1 Function VCC1 2 GND1 3 FDBK 4 VTUNE Description Interface Schematic Power supply connection for the VCO. This pin should be well bypassed close to the package with a capacitor suitable for the frequency of operation as well as a capacitor to minimize low frequency noise from the voltage supply. The ground side of the capacitors should connect immediately to ground plane. Ground connection for the VCO. Keep traces physically short and con- See pin 2. nect immediately to ground plane for best performance. In order to minimize load pulling, it is recommended that pin 2 has a different return path to ground than pin 6 (i.e., separate vias to a common ground plane). Feedback output to resonant circuit. A Colpitts oscillator is formed by See pin 4. placing a capacitor from this pin to pin 4 and from this pin to ground. A DC blocking capacitor, suitable for the frequency of operation, should be used if the external circuitry has DC present or presents a DC path to ground. See the application schematic of this data sheet for design details. Tank circuit input. A resonant circuit is placed from this pin to ground. To Bias Ckts. The capacitive side is tapped to the FDBK point and the inductive side includes a varactor for voltage tuning to provide the VCO function. A DC blocking capacitor, suitable for the frequency of operation, should be used if the external circuitry has DC present or presents a DC path VTUNE to ground. See the application schematic of this data sheet for design FDBK details. To Buffer Amps and Bias Ckts. GND1 RF OUT 6 GND2 7 VCC2 8 PD Rev A1 000908 RF output pin. This is an open-collector output and must be biased externally. A shunt bias/matching inductor to VCC and a series blocking/ matching capacitor are recommended. See Application Example Schematic. Ground connection for the buffer amplifiers. Keep traces physically short and connect immediately to ground plane for best performance. In order to minimize load pulling, it is recommended that pin 2 has a different return path to ground than pin 6 (i.e., separate vias to a common ground plane). Power supply connection for the buffer amplifiers. This pin should be well bypassed close to the package with a capacitor suitable for the frequency of operation. The ground side of the capacitor should connect immediately to ground plane. Power Down pin for the VCO and buffer amplifiers. A logic “low” (0.0 to 0.7V) turns the entire device off and supply current drops to less than 1µA. A logic “high” (≥3.0V) turns the device on. Note that the voltage on this pin should never exceed 5.5VDC. 12 PLLs and VCOs 5 12-11 RF2506 Preliminary Application Schematic PD C13 100 pF VCC C4 100 pF C2 10 pF R1 47 kΩ C1 10 pF C8 4 pF L1 27 nH 1 8 2 7 3 6 4 5 VTUNE C5 100 pF RF OUT C7 10 pF VCC D1 SMV 1249-011 C6 100 pF VCC C11 + 10 uF L2 8.2 nH C3 100 pF Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) P1 P1-1 C12 10 nF C10 + 10 uF P1-3 P2 1 VCC 2 GND 3 PD P2-1 1 VTUNE 2 GND CON3 CON3 VCC C13 100 pF 12 PLLs and VCOs PD C4 100 pF C2 10 pF R1 47 kΩ L1 27 nH C8 4 pF C1 10 pF VTUNE C6 100 pF D1 SMV1249 -011 C9* 10 pF 1 8 2 7 3 6 4 5 VCC C5 100 pF C7 10 pF 2506400- 50 Ω µstrip J1 RF OUT L2 8.2 nH VCC + C11 10 uF C3 100 pF *Not Populated 12-12 Rev A1 000908 RF2506 Preliminary Evaluation Board Layout 900MHz Board Size 1.404" x 0.986" Board Thickness 0.031”, Board Material FR-4 PLLs and VCOs 12 Rev A1 000908 12-13 RF2506 Preliminary PLLs and VCOs 12 12-14 Rev A1 000908