Maxim has a low-power, superhet receiver for 300 to 450MHz AM remote controls in cars.

"This device provides excellent receive sensitivity [-114dBm] over the entire automotive temperature range," said Maxim. "To ensure this performance, the critical functional blocks of the receiver have been designed to withstand high temperatures."

Aimed at keyless-entry systems, alarms, home security systems, remote controls, and garage door openers; the MAX7034 includes an LNA, image-rejection mixer, PLL, 10.7MHz IF filter, and analogue data-recovery circuitry. Integration of image rejection eliminates the need for an external SAW filter in many applications, claims the firm.

"The architecture greatly simplifies implementation in any 300 to 450MHz RF system," said Maxim. "The input impedance of the LNA can be adjusted by varying the off-chip degeneration inductor, allowing it to accommodate a wide range of antenna designs."

Centre frequency of the fully-differential, 44dB image-rejection mixer can be set to 315, 375, or 433MHz.
6.7mA is drawn from a 5V supply in receive mode, dropping to 3[micro]A in shutdown, operation is specified from -40 to +125[deg]C, and the chip comes in a 28 pin TSSOP package.

See http://www.maxim-ic.com