IDTF1951

6-bit 0.5 dB Digital Step Attenuator GENERAL DESCRIPTION This document describes the specification for the IDTF1951 Digital Step Attenuator. The F1951 is part of a family of Glitch-FreeTM 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 IDTF1951 is a 6-bit step attenuator optimized for these demanding applications. The silicon design has very low insertion loss and low distortion (+65 dBm IP3I.) The device has pinpoint accuracy and settles to final attenuation value within 400 nsec. Most importantly, the F1951 includes IDT’s Glitch-FreeTM 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) IDTF1951 DATASHEET 100 MHz to 4000 MHz FEATURES Glitch-FreeTM, < 0.6 dB transient overshoot Spurious Free Design 3V to 5V supply Attenuation Error < 0.2 dB @ 2 GHz Low Insertion Loss < 1.2 dB @ 2 GHz Excellent Linearity +65 dBm IP3I Fast settling time, < 450 nsec Class 2 JEDEC ESD (> 2kV HBM) Serial Interface 31.5 dB Range Stable Integral Non-Linearity over temperature 4x4 mm Thin QFN 24 pin package DEVICE BLOCK DIAGRAM Lowest insertion loss for best SNR Glitch...