Both circuits use npn transistors to levelshift the comparator's outputs by: \[V BE (R5 + R4)\]/R5 ≈ 4.5 V For single-phase outputs, you can choose a suitable single-output comparator.

Figure 1 Single-stage inductance comparator with visual and/or audible indication of unbalance. Rectangular pulses with a frequency of 1 kHz, a voltage of 10 V and with a pulse fill factor of D = 50% ...

Designed for power management applications in battery operated circuits, the TC1031 combines a low power voltage reference with a programmable hysteresis comparator and shutdown in a single 8-pin ...

The reference frequency in this circuit drives the input of an exclusive-OR gate (XOR gate U2) as well as the input to a delay circuit. Consisting of R1, C1, and comparator U1, the delay circuit ...