IDTF1950 Datasheet, PDF (1/17 Pages) Integrated Device Technology – 7-bit 0.25 dB Digital Step Attenuator

7-bit 0.25 dB Digital Step Attenuator
GENERAL DESCRIPTION
This document describes the specification for the
IDTF1950 Digital Step Attenuator. The F1950 is part of a
family of Glitch-Free^TM DSAs optimized for the demanding
requirements of communications Infrastructure. These
devices are offered in a compact 4x4 QFN package with
50 Ω impedances for ease of integration into the radio
system.
COMPETITIVE ADVANTAGE
Digital step attenuators are used in Receivers and
Transmitters to provide gain control. The IDTF1950 is a
7-bit step attenuator optimized for these demanding
applications. The silicon design has very low insertion
loss and low distortion (+65 dBm IP3_I.) The device has
pinpoint accuracy and settles to final attenuation value
within 400 nsec. Most importantly, the F1950 includes
IDT’s Glitch-Free^TM technology which results in less
than 0.6 dB of overshoot ringing during MSB transitions.
This is in stark contrast to competing DSAs that glitch as
much as 10 dB during MSB transitions (see p.10)
Lowest insertion loss for best SNR
Glitch-Free^TM when transitioning –
won’t damage PA or ADC
Extremely accurate with low distortion
Glitch-Free^TTMM
APPLICATIONS
• Base Station 2G, 3G, 4G, TDD radiocards
• Repeaters and E911 systems
• Digital Pre-Distortion
• Point to Point Infrastructure
• Public Safety Infrastructure
• WIMAX Receivers and Transmitters
• Military Systems, JTRS radios
• RFID handheld and portable readers
• Cable Infrastructure
PART# MATRIX
Part#
F1950
F1951
F1952
Freq range
Resolution
Control
IL
/ Range
150 - 4000
0.25 / 31.75
Parallel &
Serial
-1.3
100 - 4000
0.50 / 31.5 Serial Only
-1.2
100 – 4000
0.50 / 15.5 Serial Only
-0.9
Pinout
PE
HITT
HITT
IDTF1950
DATASHEET
150 MHz to 4000 MHz
FEATURES
• Glitch-Free^TM, < 0.6 dB transient overshoot
• Spurious Free Design
• 3V to 5V supply
• Attenuation Error < 0.3 dB @ 2 GHz
• Low Insertion Loss < 1.3 dB @ 2 GHz
• Excellent Linearity +65 dBm IP3_I
• Fast settling time, < 400 nsec
• Class 2 JEDEC ESD (> 2kV HBM)
• Serial & Parallel Interface 31.75 dB Range
• 4x4 mm Thin QFN 24 pin package
DEVICE BLOCK DIAGRAM
RF₁
RF₂
Bias
DEC
SPI
VMODE VDD
7
D[6:0] CLK DATA LE
ORDERING INFORMATION
Omit IDT
prefix
0.8 mm height
package
Tape &
Reel
IDTF1950NBGI8
RF product Line
Green
Industrial
Temp range
Glitch-Free^TM Digital Step Attenuator
1
Rev1 March 2012