Digital Attenuator, 3 Bit, Single Control, 28 dB, 0.5 - 2 GHz AT-242
AT-242
Digital Attenuator, 3 Bit, Single Control
28 dB, 0.5 - 2 GHz
PIN 8
PIN 1
.004
(0.10)
.050
1
(1.27)
.1890/.1968
(4.80/5.00)
-A-
BSC.
.1497/.1574
(3.80/4.00)
.0040/.0098
.013/.020 (8 PL)
.010(.25)
-B-
(.10/.25)
-C-
(.33/.51)
MMS
AB
C
.2284/.2440
(5.80/6.20)
.010(.25)
CHAMFER
(OPTIONAL)
0°/80°
MM B
.016/.050
(0.40/1.27)
1
Features
•
Single Control CMOS Logic for each bit
•
Positive Supply +3 to +5 Volts
•
Low Cost SOIC-8 Plastic Package
•
Tape and Reel Packaging Available
Description
M/A-COM’s AT-242 is a 3 bit, 4 dB step GaAs MMIC digital
attenuator in a low cost SOIC 8-lead surface mount plastic
package. The AT-242 is ideally suited for use where high
accuracy, very low power consumption and low intermodulation products are required. Typical applications include radio,
cellular, wireless LANs, GPS equipment and automatic gain/
level control circuits.
The AT-242 is fabricated with a GaAs MMIC using a mature
1-micron process. The process featur es full chip passivation for
increased performance and reliability.
SOIC-8
Oreintation
Mark
.0532/.0688
(1.35/1.75)
1. Dimensions are in inches/mm.
Absolute Maximum Ratings
Parameter Absolute Maximum
Maximum Input Power
Ordering Information
Part Number Package
AT-242 SOIC-8 Lead Plastic
AT-242TR Forward Tape and Reel
1. If specific reel size is required, consult factory for part number
assignment.
Electrical Specifications: TA = +25°C
1
1, 2
50 MHz +27 dBm
500 - 2000 MHz +34 dBm
Supply Voltage -1V, +8V
Control Voltage -1V, Vsupply +0.5V
Operating Temperature -40°C to +85°C
Storage Temperature -65°C to +150°C
1. Exceeding any one or a combination of these limits may cause
permanent damage.
Parameter Test Conditions Units Min. Typ. Max.
Reference Insertion Loss 0.5 - 1.0 GHz dB 1.4 1.6
0.5 - 2.0 GHz dB 1.7 1.9
Attenuation Accuracy 0.5 - 1.0 GHz ± (0.15 dB +3% of Attenuation Setting in dB) dB
0.5 - 2.0 GHz ± (0.3 dB = +8% of Attenuation Setting in dB) dB
VSWR 0.5 - 1.0 GHz 1.3:1 ±0.8
0.5 - 2.0 GHz 1.6:1 ±1.5
P
1dB
,
T
T
rise
fall
,
T
T
on
off
ransients
T
IP
2
IP
3
1. All measurements at 1 GHz 5Vdc in a 50Ω system unless otherwise specified. The RF ports must be blocked out side of the package from
ground or any other voltage. Insertion Loss varies at 0.003 dB/°C.
2. For two-tone input power up to +10 dBm
Input Power (Vs = +5V) 900 MHz dBm 25
10% to 90% RF, 90% to 10% RF
50% Control to 90% RF, Control to 10% RF
In-band mV 260
Measured Relative to Input Power
Measured Relative to Input Power
2
2
S
µ
S
µ
dBm 75
dBm 45
290
300
.0075/.0098
(.19/.25)
V2.00
M/A-COM Division of AMP Incorporated Q North America: Tel. (800) 366-2266, Fax (800) 618-8883 Q Asia/Pacific: Tel.+85 2 2111 8088, Fax +85 2 2111 8087
Q
Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
www.macom.com
AMP and Connecting at a Higher Level are trademarks.
Specifications subject to change without notice.
Digital Attenuator, 3 Bit, Single Control, 28 dB, 0.5 - 2 GHz AT-242
Truth Table
V1 V2 V3 Attenuation (dB)
1 1 1 Reference I.L.
10 1 4
11 0 8
10 0 12
01 1 16
00 1 20
01 0 24
00 0 28
Logic 1 = Vs ± 0.2 V
Logic 0 = 0 ± 0.2C
Typical Performance Curves
Functional Schematic
GND V3 GND RF2
8
8
1
RF1
1, 2, 3
76
4
32
GND
V2
5
16
4
V1
1. Vs = -3 VDC - 5 VDC @ 50 µA max.
can be applied to RF1 or RF2 through a 10KΩ pull-up resistor.
2. V
s
3. External DC blocking capacitors are required on all RF ports.
4. 39 pF used for data measurement.
Insertion Loss vs. Frequency Attenuation vs. Frequency
1.8
1.6
1.4
1.2
1.0
0.8
LOSS (dB)
0.6
0.4
0.2
0.0
0.1 0.6 1.1 1.5 2.0 2.5 3.0
FREQUENCY (Ghz)
VSWR vs Frequency
7.0
6.0
5.0
4.0
3.0
VSWR
2.0
1.0
0.0
0.1 0.6 1.1 1.5 2.0 2.5 3.0
16 dB Atten.
28 dB Atten.
FREQUENCY (Ghz)
(GHz)
Ins. Loss
(GHz)
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
-22
-24
ATTENUATION (dB)
-26
-28
-30
0.1 0.6 1.1 1.5 2.0 2.5 3.0
FREQUENCY (Ghz)
Attenuation Accuracy vs. Frequency
2.0
1.0
0.0
-1.0
-2.0
-3.0
-4.0
-5.0
-6.0
NOMINAL ATTENUATION (dB)
-7.0
0.1 0.6 1.1 1.5 2.0 2.5 3.0
FREQUENCY (Ghz)
(GHz)
4 dB
8 dB
16 dB
28 dB
(GHz)
M/A-COM Division of AMP Incorporated Q North America: Tel. (800) 366-2266, Fax (800) 618-8883 Q Asia/Pacific: Tel.+85 2 2111 8088, Fax +85 2 2111 8087
Q
Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
www.macom.com
AMP and Connecting at a Higher Level are trademarks.
Specifications subject to change without notice.
V2.00