7106

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

13 of 18

www.unisonic.com.tw

QW-R502-018.D

DETAILED DESCRIPTION(Cont.)

Reference Capacitor

A 0.1μF capacitor gives good results in most applications. However, where a large common mode voltage exists

(i.e.,the REF LO pin is not at analog COMMON)and a 200mV scale is used, a larger value is required to prevent

roll-ovre error. Generally 1μF will hold the roll-over error to 0.5 count in this instance.

Oscillator Components

For all ranges of frequency a 91kΩ resistor is recommended and the capacitor is selected from the equation:

f= 0.45/RC For 48kHz Clock (3 Readings/sec), C=100pF.

Reference Voltage

a transducer, there will exist a scale factor other than unity between the input voltage and the digital reading. For

instance, in a weighing system, the designer might like to have a full scale reading when the voltage from the

transducer is 0.662V. Instead of dividing the input down to 200mV, the designer should use the input voltage directly

makes the system slightly quieter and also avoids a divider network on the input.