Application of DNL9308 in the field of digital display automatic control

Photocoupler

1. Drilling pressure control alarm device: If the drilling tool pressure should be between 1200kg and 1800kg in geological drilling, exceeding or lowering this standard reflects that the drilling tool is in abnormal working state or encounters rock formations, etc., and needs to issue an alarm signal. These conditions are very easy to meet with the DNL9308 depending on the application. We set comparator a to 1800, comparator b to 1200, and use the output signal of state output port c>A and c≤B to form the alarm circuit (see the figure below). The pressure sensor and control circuit are omitted, and the reader can refer to the relevant information.

2. Thermostat controller: When the requirements are not high, we use C of DNL9308

This will control the temperature. In practice, if we use C>A and C≤B two state output ports for control, we can achieve better results. For the circuit used to control the 760C-780 °C heat treatment furnace (above), we preset the comparator a to 780 and b to 760, and use two sets of electric heaters to heat. When the furnace temperature is lower than 760"C, C B and C A (C>B), Jl is sucked, and the auxiliary heater stops heating. When the temperature drops to A, the relay J1 works again, thus stabilizing the temperature. 780C room.

3. Cryogenic chamber temperature control: (1) one of the low temperature box temperature control, the controlled temperature is between -45 ° C and -50 C, the comparator A is set to -50 ° C, and the comparator B is set to - 45 ° C. With the change of the controlled temperature, C≥A and C can be obtained.

After power-on, due to the action of capacitor C (1μF), there is a positive pulse at point A in Figure 7 to cause J to move until the temperature drops to -50 °C. The positive pulse at point B reverses the bistable, J releases, and the temperature begins to rise to - At 45 ° C, point A outputs "1". J moves again, so that the temperature is maintained between -45 ° C and -50 ° C. (2) The second temperature control of the low temperature box, the controlled temperature is between +3 °C and -20 °C, the comparator A is +3 °C, the comparator B is -20"c, so the temperature changes with the controlled temperature C> A and c