2.25 Volt Voltage Variable Absorptive
Attenuator - 40 dB, 1.8—2.5 GHz
Features
Functional Schematic
Single Positive Voltage Control 0 to +2.25 Volts
>50 dB Attenuation Range at 2.1 GHz
Low DC Power Consumption
Low Cost SOT-25 Plastic Package
Tape and Reel Packaging Available
VCC
5
VCTL
4
Description
M/A-COM’s AT-119 is a GaAs MMIC voltage variable
absorptive attenuator in a low cost, SOT-25 five-lead,
surface mount plastic package. M/A-COM fabricates the
AT-119 with a proven monolithic GaAs self-aligned gate
process that features full chip passivation for performance
and reliability
2
GND
3
RF
1
RF
100 pF
100 pF
Applications
The AT-119 is ideally suited for applications that require
fine tuning, linear attenuation with voltage, and very low
power consumption.
1. VCC = +3.3 VDC @ 50 µA max.
2. VCTL = 0 VDC to +3.3 VDC @ 50 µA max.
3. External DC blocking capacitors are required on all RF
ports.
Absolute Maximum Ratings1
Typical applications for the AT-119 include automatic gain
control circuits in satellite radio receivers and other wireless
receivers.
@ TA = +25 °C (unless otherwise specified)
Parameter
Maximum Input Power
Supply Voltage VCC
ControlVoltage VCTL
Operating Temperature
Storage Temperature
Absolute Maximum
+21 dBm
-1 V, + 8 V
-1 V, VCC +0.5 V
-40°C to +85°C
-65°C to +150°C
1. Exceeding any one or a combination of these limits may
cause permanent damage.
1
Electrical Specifications @ TA = +25 °C, Frequency = 2.4 GHz, VCC = 3.3 VDC
Parameters
Minimum Insertions Loss
Maximum Attenuation
Attenuation Slope
Return Loss
Test Conditions
Units
Min
Typ
Max
VCTL = 2.25 VDC
dB
3.0
3.2
VCTL = 0.5 VDC
dB
37
24
0.75 VDC < VCTL < 1.75 VDC
0.6 VDC < VCTL < 1.75 VDC
dB/V
dB
>12
>10
Input Power for 1 dB Change in Attenua-
tion
0 VDC < VCTL < 3.0 VDC
dBm
Input 3rd Order Intercept Point
0 VDC < VCTL < 3.0 VDC
50% VCTL to 10% / 90% RF
VCTL = 3 VDC, In-Band
dBm
nSec
mV
>20
180
10
Switching Speed
Transients
1. All measurements in a 50-τ system unless otherwise specified. The RF ports must be blocked outside of the package from
ground or any other voltage.