GENERAL DESCRIPTION

The SAA1575HL is an integrated circuit which implements a complete baseband function for Global Positioning System (GPS) receivers. It combines a 16-bit Philips 80C51XA microcontroller, 8 GPS channel correlators and related peripherals in a single IC. Users can implement a complete GPS receiver using only the SAA1575HL, the UAA1570HL front-end Philips IC (or similar), external memory and a few discrete components.

FEATURES

• Single-chip GPS baseband solution with built-in 16-bit microcontroller

• All digital, 0.5 micron CMOS technology

• Single power supply with full 3 V operation

• Separate I/O power supply pins for operation with 3 or 5 V external devices

• Up to 30 MHz system clock from on-chip crystal oscillator or external clock input

• 2 kbytes words internal data memory for fast execution

• External bus for up to 512 kbytes words data memory and 512 kbytes words program memory

• Programmable external bus timing to match external memory speed

• Chip selection outputs to reduce glue logic requirements

• Reset controller for power-down detection and servicing

• 8 GPS channel correlators driven by firmware for flexible GPS correlation algorithms

• 1 second pulse output of GPS time

• 2-bit digital IF GPS signal input synchronized to external sample clock

• 2 fully duplex UARTs for communication with host system processor and other devices

• Real-time clock with 32.768 kHz crystal and supply for low power timekeeping

• Watchdog timer

• Power-down modes under firmware control

• 100-pin LQFP package

• 50 mA supply current (typ.) when 8 GPS channels in track (approximate).