Clear signals

Linear Technology

claims that its new log detector has superior sensitivity, allowing more accurate measurement of lower levels of RF and IF signals.

The LT5537 has an operating frequency range from near DC to 1GHz. It features a measurement dynamic range of 90dB, enabling wide operating range for receivers in such applications as Automatic Gain Control (AGC) loops.

Additionally the device is said to offer exceptional accuracy over temperature, making it suitable for wireless basestations, access points, subscriber radios, and RF instrumentation subject to a wide range of environmental conditions.

The LT5537 incorporates a cascading chain of limiting amplifiers to provide a constant, linear 20mV/dB logarithmic detection function. Additionally, the device incorporates on-chip compensation circuitry to yield an accurate and stable output under varying temperature environments.

The device can measure signals within an error of +/-1dB over the worst-case temperature extremes. Moreover, the device is capable of detecting RF signal levels as low as -82dBm, significantly better than comparably priced competitive parts. On the high side, the device can measure up to +12dBm input levels.

The LT5537 operates from a single supply voltage ranging from 2.7V to 5.25V. Typical operating current is 13.5mA. The device can be shut down by applying an external 0V into an ENBL pin. When disabled, the chip typically draws 500uA quiescent current to conserve power.

The LT5537 is offered in an 8-lead 3mm x 2mm surface mount DFN package and is priced at $2.95 each in 1,000-piece quantities and is available from stock.