Programmable LPF Screens ADC Circuits

Model HMC1023LP5E is an integrated-circuit (IC) lowpass filter (LPF) with programmable gain from 0 to 10 dB across bandwidths from 5 to 72 MHz, the latter the new bandwidth used in microwave radios. This sixth-order, fully calibrated filter is ideal for baseband and intermediate-frequency (IF) signal-processing applications and can achieve more than 80-dB attenuation of unwanted signals. It adds a typical noise figure of 10 dB, with third-order intercept of typically +30 dBm and second-order intercept of typically +60 dBm. When calibrated, the programmed bandwidth is accurate within ±2.5%. The filter circuit includes an integrated analog-to-digital-converter (ADC) driver, programmable input impedance, and adjustable output common mode voltage from 0.9 to 3 V with a 2 Vpp signal. A built-in filter bypass option enables bandwidth of 100 MHz or more while maintaining programmed gain and common mode control settings. The LPF, which draws typically 240 mA from a +5-VDC supply, is housed in a 5 x 5 mm plastic leadless surface-mount package and can handle operating temperatures from -40 to +85°C.

Hittite Microwave Corp., 2 Elizabeth Dr., Chelmsford, MA 01824; (978) 250-3343, FAX: (978) 250-3373, www.hittite.com.