MACOM AT90-1283TR, AT90-1283-TB, AT90-1283 Datasheet

Digital Attenuator, 15.5 dB, 5-Bit,

V 4.00

TTL Driver, DC-3.5 GHz

AT90-1283

Features

n Attenuation: 0.5 dB Steps to 15.5 dB
n Single Positive Supply
n Contains Internal DC to DC Converter
n Low DC Power Consump tion
n Small Footprint, JEDEC Package
n Integral TTL Driver
n 50 ohm Impedance

Description

M/A-COM's AT90-1283 is a GaAs FET 5-bit digital
attenuator with integral TTL driver. Step size is 0.5 dB
providing a 15.5 dB total attenuation range. This device is
in an FQFP-N plastic surface mount package. The AT90­1283 is ideally suited for use where accuracy, fast speed,
very low power consumption and low costs are required.

CSP-1

Electrical Specifications TA = +25°C

Parameter Test Conditions Frequency Units Min Typical Max

Insertion Loss — DC - 3.5 GHz dB — 2.8 3.2

Attenuation

Accuracy

VSWR Full Range DC - 3.5 GHz Ratio — 1.6:1 1.8:1

Switching Speed 50% Cntl to 90%/10% RF

1 dB Compression —

Input IP

3

+Vcc — — V 4.75 5.0 5.25

Logic “0” Sink Current is 20 µA max. — V 0.0 — 0.8
Logic “1” Source Current is 20 µA max. — V 2.0 — 5.0

Icc Vcc min to max, Logic “0” or

Individual Bits 0.5-1-4-8 dB

Individual Bit 2 dB

Any Combination of Bits

1 to 15.5 dB

10% to 90% or 90% to 10%

—

Two-tone inputs up to +5 dBm 50 MHz

“1”

DC - 3.5 GHz
DC - 3.5 GHz
DC - 3.5 GHz

—
—

50 MHz

0.5 - 3.5 GHz

0.5-3.5 GHz

— mA — 6 10

dB
dB
dB

nS
nS

dBm
dBm — —

dB
dB

—
—
—

—
—

—
—

—
—
—

75
20

+21
+29

+35
+48

±(.3 +5% of atten setting)

±(.4 +10% of atten setting)

±(.5 +7% of atten setting)

150

50
—

—
—

—

Digital Attenuator, 15.5 dB, 5-Bit, TTL Driver, DC - 3.5 GHz

AT90-1283

V 4.00

Pin Configuration

Pin # Function Pin # Function

1 GND 17 NC
2 C8 18 NC

3 C4 19 +Vcc2
4 C2 20 NC
5 C1 21 Cp4
6 C0.5 22 NC
7 GND 23 Cp4

8 NC 24 NC

9 NC 25 -Vee
10 NC1 26 GND
11 GND 27 RF2
12 RF1 28 GND
13 GND 29 NC1
14 NC 30 -Vee
15 NC 31 NC
16 NC 32 +Vcc

1. Pins 10 & 29 must be isolated

2. Pin 19 must be connected to Pin 32.

3. Pin 25 must be connected to Pin 30.

4. .01 µF cap must be between pins 21 & 23.

5. -Vee produced internally and requires a .1 µF cap to GND.

6. +Vcc requires a .1 µF cap to GND.

3,5

3,5

2,6

Recommended PCB Layout 7

7. Application Note C2083 is available on line at
www.macom.com

Truth Table

C8 C4 C2 C1 C0.5 Attenuation

0 0 0 0 0 Loss, Reference
0 0 0 0 1 0.5 dB
0 0 0 1 0 1.0 dB
0 0 1 0 0 2.0 dB
0 1 0 0 0 4.0 dB
1 0 0 0 0 8.0 dB
1 1 1 1 1 15.5 dB

0 = TTL Low; 1 = TTL High

Specifications subject to change without notice.

n North America: Tel. [phone]
n Asia/Pacific: Tel.[phone], Fax [phone]
n Europe: Tel. [phone], Fax[phone]

Visit www.macom.com for additional data sheets and product information.

Absolute Maximum Ratings 8

Parameter Absolute Maximum

Max. Input Power

0.05 GHz

0.5 - 3.5 GHz
+Vcc +5.5V

Logic Voltages 9 -0.5 to +Vcc + 0.5V

Operating Temperature -40°C to +85°C

Storage Temperature -65°C to +125°C

8. Operation of this device above any one of these

parameters may cause permanent damange.

9. Standard CMOS TTL interface, latch-up will occur if logic

signal is applied prior to power supply.

+27 dBm
+34 dBm

2