ADG918

Data Sheet Wideband 4 GHz, 43 dB Isolation at 1 GHz, CMOS 1.65 V to 2.75 V, 2:1 Mux/SPDT ADG918/ADG919 FEATURES Wideband switch: −3 dB at 4 GHz Absorptive/reflective switches High off isolation (43 dB at 1 GHz) Low insertion loss (0.8 dB at 1 GHz) Single 1.65 V to 2.75 V power supply CMOS/LVTTL control logic 8-lead MSOP and tiny 3 mm × 3 mm LFCSP Low power consumption (<1 µA) APPLICATIONS Wireless communications General-purpose RF switching Dual-band applications High speed filter selection Digital transceiver front end switch IF switching Tuner modules Antenna diversity switching GENERAL DESCRIPTION The ADG918/ADG919 are wideband switches using a CMOS process to provide high isolation and low insertion loss to 1 GHz. The ADG918 is an absorptive (matched) switch having 50 Ω terminated shunt legs, whereas the ADG919 is a reflective switch. These devices are designed such that the isolation is high over the dc to 1 GHz frequency range. They have on-board CMOS control logic, thus eliminating the need for external controlling circuitry. The control inputs are both CMOS and LVTTL compatible. The low power consumption of these CMOS devices makes them ideally suited to wireless and general-purpose high frequency switching applications. 0 VDD = 2.5V –10 TA = 25°C –20 –30 ISOLATION (dB) –40 –50 S12 –60 –70 –80 –90 S21 03335-003 –100 10k 100k 1M 10M 100M FREQUENCY (Hz) 1G Figure 1. Off Isolation vs. Frequency 10G FUNCTIONAL BLOCK DIAGRAMS ADG918 RF1 RFC CTRL 50Ω ...