Receiver IC needs no production tweaking

Designers often implement low-cost receivers for keyless-remote-control and other applications with discrete components for minimum cost, using the venerable super-regenerative architecture, and these approaches work reasonably well. But they have one drawback: Designers must individually tune each production unit to correct for component tolerances. The Micrel MICRF008 RF-receiver IC overcomes this problem, using a sweep mode that works with cheap, relatively inaccurate transmitters (Picture). The sweep mode provides a wider yet controlled bandwidth with a 9-MHz capture range, translating to application-acceptable performance at low cost for this member of the company's QwikRadio family.

Within the 300- to 440-MHz operating range, the device supports data rates to 4.8 kbps. A typical design needs just three noncritical capacitors, one inductor, and one crystal, all driven from a one-eighth-wavelength, monopole antenna. It requires no external IF filters, which is a major advantage. The 5V SOIC-8 component costs $1.29 (1000).

Micrel Semiconductor, 1-408-944-0800, www.micrel.com.