| Part Numbert | Mfg | Packt | D/C | Descriptiont | Qty | Company/Contact |
SK5720 Price
SK5720 on stock Additional Hysteresis If additional hysteresis is desired, this can be done with the addition of three resistors using positive feedback, as shown in Figure 2. The positive feedback method slows the com- parator response time. Calculate the resistor values as fol- lows: 1) Select R3. The current through R3 should be greater than the input bias current to minimize errors. The current through R3 (IF) at the trip point is (VREF - VOUT) /R3. Consider the two possible output states when solving for R3, and use the smaller of the two resulting resistor values. The two formulas are: R3 = VREF/IF (when VOUT = 0) R3 = Vcc - VREF /IF (VOUT = VCC) 2) Choose a hysteresis band required (VHB). 3) Calculate Rl, where Rl = R3 X(VHBNCC) 4) Choose the trip point for VIN rising. This is the threshold voltage (VTHR) at which the comparator switches from low to high as VIN rises about the trip point. 5) Calculate R2 as follows: ( H O I H = O S O V ' a a i i o L N O O d s a v ) a l O A o a 1 J M l a v a a i o N I S d o W J o d a A V M O N I W 1 |
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