DC-operated 50 Hz timebase

104 Many clocks, both of the digital and the analogue type, make use of a 50 Hz timebase signal which is usually derived from the mains. In order that these clocks may also work in places were there is no mains supply available, as in cars, on boats, or, say, on a camping site, this one-chip circuit provides an accurate 50 Hz square wave output signal, DC operated 50 Hz timebase 6...15V 86498 - 1 50Hz while being fed off any DC supply voltage between 6 and 15 V (battery, solar cell array, etc.). Current con- sumption of the circuit is only 3 mA (max.). The Type SAF0300 by ITT Semicon- ductors merely requires a crystal to perform the above task, while also of- fering the possibility to adjust the exact output frequency by means of seven active low bits as listed in the pin assignment table. If a 64 Hz output frequency is desired rather than 50 Hz, the crystal may be replaced with a 4.194812 MHz type. pin function 1 Output 1 (50 Hz) 2 Adjustment pin 122 ppm 3 Adjustment pin 61 ppm...