ADCMP670

Rev. A | Page 13 of

16

APPLICATION INFORMATION

The ADCMP670 is a dual low power comparator with a

built-in 400 mV reference that operates from 1.7 V to 5.5 V.

The comparator is 1.5% accurate with a built-in hysteresis of

8.9 mV. The outputs are open-drain, capable of sinking 40 mA.

COMPARATORS AND INTERNAL REFERENCE

Each comparator has one input available externally.

Comparator A has a noninverting input and Comparator B has

an inverting input available. The other comparator inputs are

connected internally to the 400 mV reference. The rising input

threshold voltage of the comparators is designed to be equal to

that of the reference.

POWER SUPPLY

The ADCMP670 is designed to operate from 1.7 V to 5.5 V.

and GND.

INPUTS

resistor string to the input, care must be taken when choosing

resistor values. This is due to the fact that the input bias current

will be in parallel with the bottom resistor of the string. This

bottom resistor must therefore be chosen first to control the

error introduced by this bias current.

OUTPUTS

The comparator outputs are open-drain and are also limited to

voltage. These outputs are capable of sinking up to 40 mA.

Outputs can be tied together to provide a window comparator

with a single output.

ADDING HYSTERESIS

To prevent oscillations at the output caused by noise or

slowly moving signals passing the switching threshold, each

comparator has built-in hysteresis of approximately 8.9 mV.

Positive feedback can be used to increase hysteresis to the

noninverting comparator.