This circuit utilizes the TLV6710, which contains two comparators and a precision internal reference of 400 mV. The monitored voltage (VMON) is divided down by R1, R2 and R3. The voltage across R2 and R3 is compared to the 400 mV internal reference voltage (VREF). If the input signal (VMON) is within the window, the output is high. If the signal level is outside of the window, the output is low. The TLV6710 will be utilized for this example, which conveniently contains two comparators and a common precision internal reference trimmed to a 400-mV threshold. Two discrete comparators and an external reference may also be used.
- Input: Vmon = 0 V to 6 V
- Output: Vout = 0 V to 3.3 V
- Lower threshold V_L = 3.2V
- Upper threshold V_H = 4.1V
- Divider load current Imax at V_H = 10 μA