| 摘要 |
<p>PROBLEM TO BE SOLVED: To attain the driving of a voltage comparator at a high speed, with high accuracy and at a low voltage level by comparing the input voltage with the reference voltage with high accuracy even when the outputs of plural voltage comparators are connected to each other. SOLUTION: A 1st differential amplifier consists of transistors TR Q1 and Q2 and load resistances R1 and R2. A latch circuit consists of TR Q3 and Q4 of an emitter follower, the constant current sources 3 and 4, and the TR Q9 and Q10 of the positive feedback operations. A control circuit includes the TR Q5 and Q6 which select the 1st differential amplifier or the latch circuit that should be energized based on the control signals CK1 and CK2. A 2nd differential amplifier consists of the bipolar TR Q7 and Q8 which use the emitter outputs of the TR Q3 and Q4 as their inputs and a constant current source 6 and generates the voltage comparison outputs O1 and O2. Thus, a voltage comparator is obtained in such a circuit constitution.</p> |
