TLE4203 push-pull output chain circuit and waveform diagram

The TLE4203 produced by SIEMENS is an H-bridge switch driver with a freewheeling diode . The two input terminals are used to control the two half-bridges respectively. The protection functions include undervoltage
, over-temperature shutdown and preventing the output terminal from being short-circuited to the power supply or ground. . The input circuit has
a 0.7V hysteresis Schmitt trigger circuit, which has strong anti-interference ability and allows the input signal
voltage range to be -10-+40V, regardless of the power supply voltage.
    Figure 11-21 shows the electrical schematic diagram of the half-bridge. Each half-bridge NPN power transistor push-pull
output stage base drive circuit is equipped with interlocking comparators Kl and K2,
which prevent the upper and lower switches from flowing through when the IC is operating at high frequency. Otherwise, the through current can
reach a large value within hundreds of nanoseconds, which will increase the switching power consumption, cause serious heating, reduce efficiency, and even
damage the power transistor. Its function is explained as follows: two comparators are set with a reference voltage
y WF, and their outputs are h. and VK. Cross-coupled to the AND gate input. Assume that
the control signal V is in the initial state . ,for. ,Output current,. is the reverse direction, that is, V. Cutoff, V, conduction
work. When phase commutation is required, it becomes V: cut-off, V. conduction. Control the signal mine. ． becomes
l. Due to the transistor charge storage effect, y: Vnc. Gradually decreases t but the collector current
,. will quickly drop to a low value. At this time, K2 still maintains a low level to block the AND gate. Only when
BE: drops below VREF, does comparator K2 flip to 1, allowing transistor V- to conduct
, J. become positive. Figure 11-22 shows the relevant parts of the interlock circuit
when it is working .