RF2410 9 UHF PROGRAMMABLE ATTENUATOR Typical Applications • Power Control in Communication Systems • Commercial and Consumer Systems • CMOS Compatible Programmable • Portable Battery-Powered Equipment Attenuators Product Description .157 .150 1 .050 .244 .228 Si Bi-CMOS SiGe HBT ü .065 .043 8 °MAX 0°MIN 9 Optimum Technology Matching® Applied GaAs HBT .010 .004 .393 .386 .050 .016 Si BJT .018 .014 .010 .007 ATTENTUATORS AND SWITCHES The RF2410 is a multistage monolithic programmable attenuator. The device is built using a Gallium Arsenide process technology and has an attenuation programmability over a 38dB range in 2dB steps. The attenuation is set by five bits of digital data. The input and output of the device have a low VSWR 50Ω match. The RF output can drive up to +10dBm. This unit is intended for use in systems that require RF transmit power control by digital means. A typical application is in dual mode IS-54/55 compatible cellular transceivers. No negative supply voltages are required, and the unit has a power down feature which reduces the current consumption to less than 0.5mA. Package Style: SOP-16 GaAs MESFET Si CMOS Features • Single 5V Supply IN 1 16 VD • 0dB to 38dB Attenuation Range 15 PD • 4 dB Insertion Loss 14 G2 • 5-bit Digitally Controlled Attenuation 2 dB GND 2 GND 3 4 dB GND 4 13 G4 • 500MHz to 2100MHz Operation 8 dB GND 5 GND 6 12 G8A 8 dB GND 7 11 G8B 10 G16 16 dB GND 8 9 OUT Functional Block Diagram Rev B1 010329 • Digitally Controlled Power Down Mode Ordering Information RF2410 RF2410 PCBA UHF Programmable Attenuator Fully Assembled Evaluation Board RF Micro Devices, Inc. 7625 Thorndike Road Greensboro, NC 27409, USA Tel (336) 664 1233 Fax (336) 664 0454 http://www.rfmd.com 9-1 RF2410 Absolute Maximum Ratings Parameter Supply Voltage Power Down Voltage Operating Ambient Temperature Storage Temperature Parameter Rating Unit -0.5 to +7.0 -0.5 to VDD +0.4 -40 to +85 -40 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 500 to 1000 500 to 2100 4 0 to 38 0.25 MHz MHz dB dB dB Overall Frequency Range Frequency Range Insertion Loss Attenuation Range Gain Flatness 5.5 Condition T=25°C and 5V at 900MHz 0dB to 38dB Attenuation Range 0dB to 20dB Attenuation Range In any 50MHz band Input Input Impedance Input VSWR Input 1dB Compression 10 50 1.3:1 14 1.0 2.9 6.7 6.4 14.1 35.0 2, 4, 8, 8, 16 2.0 4.0 8.0 8.0 16.0 38.0 2.5 VDD Ω dBm Attenuation Attenuation Settings Accuracy ATTENTUATORS AND SWITCHES 9 dB dB dB dB dB dB dB CMOS Level, 5 bits 2dB Step 4dB Step 8dB Step (A) 8dB Step (B) 16dB Step All bits on V V mA ns Voltage Supplied to input Voltage Supplied to input Into each control line dBc dBc Ω With 0dBm output in each of 2 tones 12 0.75 V V mA mA Specifications Operating Limits Operating Power Down 0.3 V V 3.2 5.4 9.8 10.5 19.3 42.0 Attenuation Control Attenuation “ON” Voltage Attenuation “OFF” Voltage Current Response Time 0.4 <10 0.3 1.0 Output IM3 Harmonic Output Output Impedance Output VSWR -30 -40 50 1.3:1 Power Supply Voltage 5 4.5 to 6.0 6 0.4 Current Power Down Power “ON” Voltage Power “OFF” Voltage 9-2 2.5 VDD Voltage supplied to input; device is “ON” Voltage supplied to input; device is “OFF” Rev B1 010329 RF2410 Pin 1 Function RF IN Description Interface Schematic RF Input. This pin is not DC blocked, and an external blocking capacitor is recommended. The value depends on the frequency used. RF IN 2 GND 3 4 5 6 7 8 9 GND GND GND GND GND GND RF OUT Ground connection. Keep traces physically short and connect immediately to the ground plane for best performance. Each ground pin should be connected to the ground plane individually, rather than using one trace and/or via for all ground pins. This will give better step accuracy. Same as pin 2. Same as pin 2. Same as pin 2. Same as pin 2. Same as pin 2. Same as pin 2. RF Output. This pin is not DC blocked, and an external blocking capacitor is recommended. The value depends on the frequency used. RF OUT G16 11 G8B 12 G8A 13 G4 14 G2 15 PD 16 VDD Rev B1 010329 Control pin for the 16dB attenuator. This pin has an internal pull-down resistor, so when the pin is not connected the attenuator will be turned off. For operating frequencies above 1GHz this bit should always be left "off". Control pin for the 8dB attenuator. This pin has an internal pull-down resistor, so when the pin is not connected the attenuator will be turned off. Control pin for the 8dB attenuator. This pin has an internal pull-down resistor, so when the pin is not connected the attenuator will be turned off. Control pin for the 4dB attenuator. This pin has an internal pull-down resistor, so when the pin is not connected the attenuator will be turned off. Control pin for the 2dB attenuator. This pin has an internal pull-down resistor, so when the pin is not connected the attenuator will be turned off. Power Down control pin. This pin has an internal pull-up resistor to VDD of 10kΩ. When this pin is "low" the circuits are turned off. A "low" means as close to 0V as possible, to ensure minimum current consumption when turned off. 9 Gxx ATTENTUATORS AND SWITCHES 10 Same as pin 10. Same as pin 10. Same as pin 10. Same as pin 10. PD Power supply pin. An external RF bypass capacitor is recommended. 9-3 RF2410 Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) 50 Ω µstrip J1 RF IN 2410400 Rev A C1 100 pF 1 P1-3 16 C2 33 pF 2 dB 2 15 3 4 dB 4 1 G2 P2-2 2 G4 P2-3 3 G8A P2-5 5 NC 6 NC 7 NC 8 9 ATTENTUATORS AND SWITCHES 9 NC 9-4 5 P2-1 4 10 14 P1-1 P2-1 13 P2-2 12 P2-3 11 P2-4 8 dB P2 P2-4 C4 33 pF 6 8 dB 7 P2-5 10 16 dB G8B 8 50 Ω µstrip 9 C3 100 pF G16 J2 RF OUT P1 P1-1 GND P1-3 1 PD 2 GND 3 VDD Rev B1 010329 RF2410 Evaluation Board Layout Board Size 2.020” x 2.020” Board Thickness 0.031”, Board Material FR-4 ATTENTUATORS AND SWITCHES 9 Rev B1 010329 9-5 RF2410 Attenuation vs. Frequency 1. Using All Bits, 2. Not Using G16 CH1 S 21 log MAG 5 dB/ REF 0 dB CH1 C2 C2 Smo Smo START .300 000 MHz STOP 3 000.000 000 MHz S 21 START log MAG 5 dB/ REF 0 dB .300 000 MHz STOP 3 000.000 000 MHz RF2410 Attenuation Error from Ideal over Temperature 900 MHz 3.00 2.50 2.00 1.50 1.00 0.50 0.00 -0.50 -1.00 -1.50 -2.00 -2.50 T= -40 C T= +25 C 38 34 30 26 30 26 22 18 22 18 14 10 14 10 6 T= +85 C 2 Error (dB) ATTENTUATORS AND SWITCHES 9 Desired Attenuation (dB) 9-6 Rev B1 010329 -10 Rev B1 010329 30 28 26 24 30 28 26 24 22 20 18 16 22 20 18 16 14 12 10 8 14 12 ATTENTUATORS AND SWITCHES 38 1700 MHz 11111 -7.5 36 -5 11110 -2.5 34 0 11101 2.5 32 5 11100 11011 11010 1300 MHz 11001 11000 10111 10110 10101 10100 900 MHz 10011 10010 10001 10000 01111 01110 500 MHz 01101 01100 01011 01010 01001 01000 00111 00110 10 8 6 4 2 2 26 28 30 32 34 36 38 11001 11010 11011 11100 11101 11110 11111 24 22 20 18 16 22 20 18 16 14 12 10 8 14 12 10 8 6 4 24 -10 11000 -7.5 30 -5 28 -2.5 10111 0 10110 Average 26 2.5 10101 10100 10011 10010 10001 10000 01111 01110 01101 01100 01011 01010 01001 01000 00111 00110 00101 00100 00011 00010 00001 Error (dB) 5 00101 00100 00011 00010 00001 Error (dB) RF2410 Typical Characteristics at 900MHz Attenuation Variation from Ideal Digital Control Setting Typical Attenuation Error 9 Digital Control Setting 9-7 ATTENTUATORS AND SWITCHES RF2410 9 9-8 Rev B1 010329