RF2451 4 3V LOW NOISE AMPLIFIER Typical Applications • GSM Handsets • IF or RF Buffer Amplifiers • CDMA Handsets • Driver Stage for Power Amplifiers • TDMA Handsets • Oscillator Loop Amplifiers D R E F2 S 37 IG 1 N S The RF2451 is a general purpose, low-cost, high performance low noise amplifier designed for operation from a 2.7V to 4V supply with low current consumption. The attenuation of the device is controlled when in power down mode, providing a known gain step. The RF2451 is available in a small industry-standard MSOP-8 surface mount package, enabling compact designs which conserve board space. The design features accurate PTAT (Proportional To Absolute Temperature) biasing scheme using band gap cells. .120 .116 .026 .120 SiGe HBT Si CMOS d ISET 2 VCC 3 ENABLE 4 pg r N S ee O T U RF OUT 1 10°MAX 0°MIN .009 .005 Package Style: MSOP-8 Features • 700MHz to 2000MHz Operation • 2.7V to 3.6V Single Supply • +5dBm Input IP3 at 3.0mA 8 RF IN • 12dB Gain at 1950MHz 7 GND1 • 1.8dB Noise Figure at 1950MHz 6 GND2 • 17dB Gain Step Bias Circuits 5 IPSET Functional Block Diagram Rev A8 000822 .036 .032 .116 GaAs MESFET FO ad R e !Si Bi-CMOS GaAs HBT .016 .010 1 ct N P ro E du W Si BJT .006 .002 .196 .190 .027 .017 Optimum Technology Matching® Applied 4 GENERAL PURPOSE AMPLIFIERS Product Description Ordering Information RF2451 RF2451 PCBA 3V Low Noise Amplifier 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 4-247 RF2451 Supply Voltage Supply Current Operating Ambient Temperature Storage Temperature Parameter Unit 4.0 20 -40 to +85 -40 to +150 V mA °C °C Specification Typ. Max. 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). Unit Condition T=27°C, VCC =2.7V, VIPSET =0V, VENABLE =2.7V Overall Frequency Range 700 to 2000 LNA Performance MHz Freq=1.95GHz Gain Noise Figure Input IP3 Input VSWR Output VSWR Off Mode Gain Gain Noise Figure Input IP3 Off Mode Gain 10.5 12.5 1.6 +8 5:1 +4.5 1.5:1 Internal current setting “ON” External current setting “ON” Current into ISELECT Power Control Power “ON” Voltage Power “OFF” Voltage Current into ENABLE CMOS Low CMOS High CMOS High CMOS Low FO ad R e Power Supply 2.7 to 3.6 2.9 d Operating Voltage Operating Current Leakage Current At 2.9mA (Noise match) VENABLE =0V Freq=836MHz VENABLE =0V 1 V V µA Voltage on IPSET Voltage on IPSET VISELECT =2.7V 1 V V µA Voltage on ENABLE Voltage on ENABLE VENABLE =2.7V 5 1 V mA µA VCC =2.7V, Internal current setting VENABLE =0V uc t Current Control N P ro EW d -5.0 17 1.6 0 -8 dB dB dBm dB dB dB dB dB dBm dB pg r N S ee O T U GENERAL PURPOSE AMPLIFIERS 4 Min. Rating D R E F2 S 37 IG 1 N S Absolute Maximum Ratings Parameter 4-248 Rev A8 000822 RF2451 ISET 3 4 VCC ENABLE 5 IPSET 6 7 GND2 GND1 8 RF IN Interface Schematic RF output pin. Bias for the LNA is provided through this pin, hence it should be connected to VCC through an inductor. This pin sets the current for the device. A resistor to ground of 1kΩ provides a current of 17.5mA. The condition for optimal IP3 is to use the internal current setting option and leave this pin open (no connect). Power supply for the bias circuits. Power down control. This is a CMOS input. When this pin is CMOS “high” the device is enabled. When the level is CMOS “low” the device is shut off and a controlled attenuator is turned on. This pin selects the internal current setting when CMOS level “low”, and the external current setting when this pin is CMOS level “high”. The current is set to 2.8mA using the internal current setting, and can be up to 20mA using the external current setting. Ground connection for the bias circuits. 4 GENERAL PURPOSE AMPLIFIERS 2 Description D R E F2 S 37 IG 1 N S Function RF OUT Ground connection for the LNA. Keep traces physically short and connect immediately to ground plane for best performance. RF input pin. This pin is not internally DC blocked and requires an external blocking capacitor. pg r N S ee O T U d FO ad R e uc t N P ro EW d Pin 1 Rev A8 000822 4-249 RF2451 Application Schematic 1.95GHz VCC 1.5 pF 3.3 nH RF OUT 22 nF 1 8 2 7 VCC 4 3 10 nF D R E F2 S 37 IG 1 N S 1 kΩ RF IN 6 GENERAL PURPOSE AMPLIFIERS Bias Circuits ENABLE 4 IPSET 5 Application Schematic 836MHz RF OUT 18 nH 1 1 kΩ 2 VCC 3 uc t 1 pF N P ro EW d VCC 22 nF RF IN 8 7 82 nH 6 Bias Circuits 4 5 IPSET pg r N S ee O T U d FO ad R e ENABLE 4-250 Rev A8 000822 RF2451 Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) VCC R1 1 kΩ VCC C1 22 nF 1 8 2 7 3 J2 LNA INPUT L2 10 nH 4 6 GENERAL PURPOSE AMPLIFIERS J1 LNA OUTPUT L1 3.3 nH D R E F2 S 37 IG 1 N S C2 1.5 pF Bias Circuits ENABLE 4 5 IPSET 2451400A VCC ENABLE IPSET + - C3 1 nF C4 1 uF + C5 22 nF VCC + 2.7 V - VCC 2 ENABLE 3 IPSET 4 CON4 GND pg r N S ee O T U d FO ad R e uc t N P ro EW d ENVCC 2.6 V P1 1 Rev A8 000822 4-251 RF2451 Evaluation Board Layout Board Size 1” x 1” D R E F2 S 37 IG 1 N S Board Thickness 0.031”, Board Material FR-4 pg r N S ee O T U d FO ad R e uc t N P ro EW d GENERAL PURPOSE AMPLIFIERS 4 4-252 Rev A8 000822