Product News:

Log Amplifier operates from near DC to 1 GHz.

Press Release Summary:

Log Amplifier operates from near DC to 1 GHz.

Oct 04, 2005 - Featuring dynamic range of 90 dB, Model LT5537 allows accurate measurement of lower levels of RF and IF signals. Cascading chain of limiting amplifiers provide constant, linear 20 mV/dB logarithmic detection function, while on-chip compensation circuitry yields stable output under varying temperatures. Housed in 3 x 2 mm surface-mount DFN package, device measures signals within error of ±1 dB over worst-case temperature extremes, and can detect RF signal levels as low as -82 dBm.

Linear Technology Corp. - Milpitas, CA

Original Press Release

Wide Dynamic Range Log Amplifier Enhances Sensitivity of RF Power Measurements

Press release date: Aug 25, 2005

MILPITAS, CA - August 25, 2005 - A new high performance log detector from Linear Technology has superior sensitivity, allowing more accurate measurement of lower levels of RF and IF signals. The LT5537 has a wide 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 offers 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 has superior sensitivity, 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. The device requires fewer external components than alternative solutions, providing a compact, cost effective solution. It is priced at $2.95 each in 1,000-piece quantities and is available from stock.

Summary of Features: LT5537 Frequency Range: Low Frequency to 1GHz Dynamic Range: 90 dB Accurate Over Temperature: +/-1dB Sensitivity: - 82dBm Small Form Factor: 3mm x 2mm DFN Package

Company Background Linear Technology Corporation was founded in 1981 as a manufacturer of high performance linear integrated circuits. Linear Technology products include high performance amplifiers, comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery chargers, data converters, communications interface circuits, RF signal conditioning circuits, and many other analog functions. Applications for Linear Technology's high performance circuits include telecommunications, cellular telephones, networking products such as optical switches, notebook and desktop computers, computer peripherals, video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer products such as digital cameras and MP3 players, complex medical devices, automotive electronics, factory automation, process control, and military and space systems.

LT and LTC are registered trademarks of Linear Technology Corp. North America and General Information John Hamburger Tel: (408) 432-1900 ext. 2419

Doug Dickinson Tel: (408) 432 1900 ext. 2233