SA8025A

INTEGRATED CIRCUITS SA8025A Low-voltage 1.8GHz fractional-N synthesizer Product specification IC17 Data Handbook 1996 Oct 15 Philips Semiconductors Philips Semiconductors Product specification 1.8GHz low-voltage Fractional-N synthesizer SA8025A DESCRIPTION The SA8025A is a monolithic low power, high performance dual frequency synthesizer fabricated in QUBiC BiCMOS technology. The SA8025A is an improved version of the SA8025, suitable for narrow band systems like the Japan Personal Digital Cellular (PDC) system. The new design improves the performance of the fractional spur compensation circuitry. The new version is pin-for-pin compatible with the previous version. Featuring Fractional-N division with selectable modulo 5 or 8 implemented in the Main synthesizer to allow the phase detector comparison frequency to be five or eight times the channel spacing. This feature reduces the overall division ratio yielding a lower noise floor and faster channel switching. The phase detectors and charge pumps are designed to achieve phase detector comparison frequencies up to 5MHz. A four modulus prescaler (divide by 64/65/68/73) is integrated on chip with a maximum input frequency of 1.8GHz at 3V. Programming and channel selection are realized by a high speed 3-wire serial interface. A 1GHz version (SA7025DK) is also available with the same pinout. PIN CONFIGURATION DK Package CLOCK DATA STROBE VSS RFIN RFIN VCCP REFIN RA AUXIN VDD TEST LOCK RF RN VDDA PHP PHI VSSA PHA 1 2 3 4 5 ...