RF2681 Preliminary 4 W-CDMA LINEAR VARIABLE GAIN DRIVER AMPLIFIER Typical Applications • General Purpose Driver Amplifier Product Description The RF2681 is a linear variable gain amplifier specifically designed for PA driver applications in W-CDMA handsets. The device maintains excellent linearity over a 30dB gain control range, while providing a maximum of 26dB gain. The IC is manufactured on an advanced Gallium Arsenide Heterojunction Bipolar Transistor Process and is provided in an extremely small 3mmx3mm, 12-pin, leadless chip carrier. 0.80 0.65 1.00 0.85 4 3.00 sq. 0.65 0.30 0.60 0.24 typ 2 4 PLCS 0.30 0.18 1.25 sq. 0.95 0.75 0.50 12° max 0.05 0.01 0.23 0.13 0.50 4 PLCS Dimensions in mm. NOTES: Shaded Pin is Lead 1. 2 Dimension applies to plated terminal and is measured between 0.02 mm and 0.25 mm from terminal end. Pin 1 identifier must exist on top surface of package by identification mark or 3 feature on the package body. Exact shape and size is optional. 1 4 5 Optimum Technology Matching® Applied Si BJT Si Bi-CMOS ü GaAs HBT GaAs MESFET SiGe HBT Si CMOS Package Warpage: 0.05 mm max. Die thickness allowable: 0.305 mm max. Package Style: LCC, 12-Pin, 3x3 Features GC NC RF OUT • 30dB Linear Gain Control Range 12 11 10 • 26dB Maximum Gain • Single 2.7V to 3.3V Supply • High Linearity Over Entire Gain Control VCC1 1 9 GND VREG 2 8 GND VCC2 3 7 GND Functional Block Diagram Rev A1 010824 • 9dBm Output Drive Available 6 RF IN 5 NC PD 4 Range Ordering Information RF2681 RF2681 PCBA W-CDMA Linear Variable Gain Driver 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 4-43 GENERAL PURPOSE AMPLIFIERS • PA Driver Amplifier for W-CDMA Handsets RF2681 Preliminary Absolute Maximum Ratings Parameter Supply Voltage Operating Ambient Temperature Storage Temperature Parameter Rating Unit -0.5 to +3.6 -40 to +85 -40 to +150 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 1800 to 2100 30 40 MHz dB dB/V Condition Overall GENERAL PURPOSE AMPLIFIERS 4 Usable Frequency Range Linear Gain Control Range Gain Control Slope W-CDMA Operating Frequency Small Signal Gain Output IP3 Noise Figure Input VSWR Output VSWR Maximum Linear Output Power ACPR1 (5MHz Offset) 24 -7 +22.0 8 1920 to 1980 26 -5 +24.0 3 1.4:1 1.8:1 9 ACPR2 (10MHz Offset) 29 -3 +26.0 MHz dB VGC =2.4V (Maximum Gain) VGC =0V (Minimum Gain) dBm dB VGC =2.4V (Maximum Gain) Small signal Over entire gain control range -48 dBm dBc W-CDMA ACPR<-43dBc Over entire gain control range. PIN such that POUT =9dBm at maximum gain setting. W-CDMA reverse link modulation. -62 dBc 3.3 V V mA µA mA 2:1 2:1 Power Supply Supply Voltage Gain Control Voltage Supply Current VGC Current 4-44 2.7 0 to 2.4 38 220 1.7 Operating range Useful range VCC =2.7V VGC =2.4V (Maximum Gain) VGC =0.2V Rev A1 010824 RF2681 Preliminary Function VCC1 2 VREG 3 4 VCC2 PD 5 NC 6 RF IN 7 8 9 10 GND GND GND RF OUT 11 12 NC GC Pkg Gnd GND Rev A1 010824 Description Interface Schematic DC supply for internal bias circuitry. This pin should be tied to VCC, and must be bypassed with an RF capacitor. The trace length between the pin and the bypass capacitor should be minimized. The ground side of the capacitor should connect immediately to the ground plane. DC supply for internal bias circuitry. This pin should be tied to a 2.7V supply for proper operation. Increasing this voltage above 2.7V will result in increased current drain and is not recommended. Same as pin 1. Power down pin. This pin should be brought below 1V for proper operation. The device is turned off when the voltage on this pin increases above 2V. This pin is not internally connected, but should be grounded, if possible, to improve RF isolation. Please refer to the evaluation board layout. RF input pin. This pin requires external matching components, and is DC-coupled. Please refer to the applications schematic for recommended matching components. Ground 4 GENERAL PURPOSE AMPLIFIERS Pin 1 Ground Ground RF output pin. This pin requires an external matching network. VCC is provided through an inductor of that network. Please refer to the applications schematic for recommended matching components. Same as pin 5. Gain control pin. This pin allows the gain of the amplifier to be varied in a continuous “analog” fashion. With an applied voltage of 0.2V or less, the amplifier exhibits the minimum gain. In the region between 0.2V and 2.25V, the amplifier gain in dB depends on the voltage in a roughly linear manner. Above 2.25V, the amplifier gain is set for maximum. Ground connection for the device “die flag”. The backside of the package should be soldered to a top side ground pad which is connected to the PC board ground plane through multiple vias. 4-45 RF2681 Preliminary Application Schematic W-CDMA VCC OUT VGC 3 pF 10 nH 2 nH 47 nF 47 nF VCC 4 12 11 47 nF 10 1 9 2 8 3 7 GENERAL PURPOSE AMPLIFIERS 51 Ω VREG 47 nF VCC 4 5 6 2.2 nH 1 nF 3.6 nH VENABLE 47 nF 3 pF IN 4-46 Rev A1 010824 RF2681 Preliminary Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) 50 Ω µstrip VCC C9 3 pF VGC L3 2 nH C1 47 nF C2 47 nF VCC 12 R1 51 Ω VREG C3 47 nF 11 C8 47 nF 10 1 9 2 8 3 7 4 VCC C4 1 nF L2 10 nH 5 L4 2.2 nH 4 GENERAL PURPOSE AMPLIFIERS J2 OUT 6 L1 3.6 nH VENABLE C5 47 nF P2-1 P1 P1-1 1 VCC 2 GND 3 GND CON3 Rev A1 010824 P2-2 C11 1 uF + P2-4 C12 1 uF P2 1 50 Ω µstrip J1 RF IN C13 1 uF + + C10 1 uF C6 3 pF VGC 2 VCC ZLO 3 GND VCC 4 + CON4 P3 P3-1 P3-3 C14 1 uF 1 VCC ZHI 2 GND 3 V ENABLE + CON3 4-47 RF2681 Preliminary Evaluation Board Layout Board Size 2.0” x 2.0” Board Thickness 0.031”, Board Material FR-4 GENERAL PURPOSE AMPLIFIERS 4 4-48 Rev A1 010824 RF2681 Preliminary Input SWR versus VGC Output SWR versus VGC 2.0 1.50 1.9 1.45 1.8 1.40 SWR SWR 1.7 1.35 1.6 1.5 1.30 4 1.4 SWR, -40º SWR, -40º 1.3 SWR, 25º SWR, 25º SWR, 85º SWR, 85º 1.20 0.00 GENERAL PURPOSE AMPLIFIERS 1.25 1.2 0.50 1.00 1.50 2.00 0.0 2.50 0.5 1.0 VGC (V) 30.0 1.5 2.0 2.5 VGC (V) Gain versus VGC ACPR versus VGC VCC = 2.7 V, Freq = 1950 MHz Maximum Output Power: VCC = 2.7 V, Freq = 1950 MHz -30.0 -34.0 25.0 -38.0 20.0 -42.0 ACPR (dBc) Gain (dB) 15.0 10.0 5.0 -46.0 -50.0 -54.0 -58.0 0.0 ACPR, -40º -62.0 Gain, -40º -5.0 ACPR, 25º Gain, 25º ACPR, 85º -66.0 Gain, 85º -10.0 -70.0 0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.5 1.0 VGC (V) 30.0 1.5 2.0 2.5 VGC (V) OIP3 versus VGC ICC versus VGC Maximum Output Power: VCC = 2.7 V, Freq = 1950 MHz VCC = 2.7 V, Freq = 1950 MHz 40.0 25.0 39.0 38.0 15.0 ICC (mA) OIP3 (dBm) 20.0 10.0 Icc, -40º 37.0 Icc, 25º Icc, 85º 5.0 36.0 OIP3, -40º 0.0 OIP3, 25º OIP3, 85º -5.0 35.0 0.0 0.5 1.0 1.5 VGC (V) Rev A1 010824 2.0 2.5 0.0 0.5 1.0 1.5 2.0 2.5 VGC (V) 4-49 RF2681 Preliminary GENERAL PURPOSE AMPLIFIERS 4 4-50 Rev A1 010824