hf/rf ZONE Products for the week of April 14, 2003
Agilent says . . .
ATF-58143: Enhancement-Mode PHEMT FET for 450 MHz
To 6 GHz Wireless
Single Voltage Operation, 0.5 dB Noise Figure, 16.5 dB Gain,
30.5 dBm OIP3 Assures Excellent Front-End LNA Performance
Agilent Technologies Inc. announced a high linearity E-pHEMT (enhancement-mode pseudomorphic high electron mobility transistor) field effect transistor (FET) designed for low noise, high dynamic range operation in cost-sensitive wireless infrastructure applications that operate between 450 MHz and 6 GHz.
At 3V, 30 mA and 2 GHz, the single voltage Agilent ATF-58143 E-pHEMT FET features 0.5 dB noise figure with +16.5 dB associated gain, combined with +30.5 dBm third-order output intercept point (OIP3) and +16.5 dBm linear output power (1 dB gain compression). It's ideal for the first and second stage of front-end LNAs (low-noise amplifiers) in cellular/PCS/WCDMA base station, wireless local loop, fixed wireless access and other high-performance applications that operate between 450 MHz and 6 GHz. The ATF-58143 delivers high linearity of 30.5 dBm OIP3 at low power consumption of only 30 mA at 3V, which reduces heat generation in today's compact equipment designs. Single-voltage operation also eliminates the need for voltage inverter circuitry or dual-voltage voltage supplies.
Agilent remains the industry's only supplier of E-pHEMT devices that
feature single-voltage operation, which greatly simplifies voltage supply
design. The single 3V supply voltage makes this new Agilent E-pHEMT FET
the logical choice to replace single-voltage HBT (heterojunction bipolar
transistor), and dual-voltage conventional PHEMT and GaAs HFET (heterostructure
FET) devices.
analogZONE Says . . .
Agilent is riding high with its E-pHEMT process and the numbers produced here are remarkable. With just a single supply, a major benefit of the process for the circuit designer, this part is producing a magical 0.5 dB noise figure with 16.5 dB gain - and those are the numbers for 2 GHz! Down at 900 MHz the numbers are 0.3 dB and 23.1 dB. If you raise the supply rail from 3 V to 4 V you can squeeze another 0.8 dB of gain at 2 GHz without affecting the noise figure, but at that rail the gain at 900 MHz actually falls by about 0.6 dB.
The output IP3 at 2 GHz is 30.5 dBm and at 900 MHz it is 28.6 dBm, while P1dB is 19 dBm at 2 GHz and 18 dBm at 900 MHz (all 3-V rail.) The output impedance is an interesting 51 - j3.3 while the input is a controllable 28.2+j3.3. S parameters are given in the data sheet for frequencies from 100 MHz to 18 GHz at both 3-V and 4-V rails.
The curves suggest that the part is very usable up to 6 GHz and beyond for some applications. They are going to be ideal parts for cellular base station LNAs (across the frequency spectrum) and for the first, second and pre-driver stages in wireless loops at 3/4 GHz. It will quickly become a first-choice component for low-noise high-frequency designs.
The ATF-58143 is in production in a SOT-343 and is priced at $1.08 in <25-k piece lots.