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1525 Analog Compass

The 1525 Analog Compass requires regulated 5.00 volts DC input to output a DC ratiometric signal. The input should be "spike" and polarity protected if operated from a vehicular power supply. Power consumed is approximately 18 to 19 mils (0.018 to 0.019 amps) when using a 5.00 volt power supply.

The output closely resembles a sine-cosine set of curves which cross at approximately 2.5 volts and peak at approximately 2.88 volts and floor at approximately 2.12 volts. Each output will drive up to 4 mA. The Vcc and grounds may be common connected.

The sensor is constructed to operate in a vertical position with the lead pins down. The sensor is designed to measure the direction of the horizontal component of the earth's field (Compass component). If the sensor is tilted off vertical, it begins to sense some of the vertical component of the Earth's field which may introduce some error. For practical purposes, up to approximately 12° tilt, as with any compass, is considered acceptable.

Compass component

The sensor is damped slightly so that the indications are similar to those of a standard liquid-filled compass. That is, if the reading is displaced 90°, it will return to proper indication in 2.5 to 3.5 seconds, with no overswing. Sensors can be furnished with zero damping on request. Undamped sensors can be made to "flutter" caused by quickly passing stray magnetic anomalies near the sensor or by mechanical vibration of the sensor.

The sensor is not affected by exposure to large flux fields; outside flux is unlimited up to 1,000 gauss.

The operating temperature limits are -20° C to +85º C. .

The sensor weighs approximately 2.25 grams. The major dimensions appear in the drawing at right.

SIN-COS Compass Resolution

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