Constant Current Limiting Circuit: A block of series regulation using simple Constant Current Limiting Circuit is shown in the Fig. 2.119. It is also called short circuit protection circuit as it provides protection against short circuiting. The resistance R4 is added in series with the pass transistor Q1 and the load which is called current sensing […]
Constant Current Limiting Circuit Read More »
Protection Circuits in Regulators: Protection Circuits in Regulators- The series regulator using transistors has no short circuit protection. If the load terminals are shorted accidentally then, Large amount of load current will flow. The pass transistor Q1 will get destroyed. The diodes used in unregulated power supply, supplying the input voltage Vin to regulator circuit
Protection Circuits in Regulators Read More »
Negative Voltage Regulator: Connections for getting negative voltage regulator are shown in Fig. 2.116. An external PNP transistor, Q1 is connected. Resistances can be from 1 kΩ to 10 kΩ. If magnitude of -Vi is less than 9V, connect VCC+ and VC to a positive supply such that VCC+ to VCC- is greater than 9V, for proper
Negative Voltage Regulator Read More »
Positive High Voltage High Current Regulator: Positive High Voltage High Current Regulator – For this type, output voltage from +7V to +37V and load current IL > 150 mA. For this a external transistor Q1 is connected, as shown in the Fig. 2.115. For this different expressions are similar to basic high voltage regulator and reproduced
Positive High Voltage High Current Regulator Read More »
Basic Positive High Voltage Regulator: The Basic Positive High Voltage Regulator is shown in Fig. 2.114 For this type, output voltage varies from +7V to +37V and IL ≤ 150 mA. The non-inverting terminal connected to Vref through R3 . Due to this arrangement the error amplifier acts as non-inverting amplifier. The gain is The output
Basic Positive High Voltage Regulator Read More »
Low Voltage High Current Regulator: Fig. 2.113 shows the Low Voltage High Current Regulator Circuit. Output voltage from +2 to +7 V and load current can be more than 150 mA. For this one transistor is connected externally, shown as Q1 in the Fig. 2.113. The functional equations are similar to that of basic low voltage
Low Voltage High Current Regulator Read More »
Basic Low Voltage Regulator using IC 723: Fig. 2.112 shows the Basic Low Voltage Regulator using IC 723. The resistor, Rsc is connected between CL and CS pins. The current limit transistor remains non-conductive unless drops across Rsc is 0.6 V (equal to VBE drop). The value of Rsc can be found out by following equation
Basic Low Voltage Regulator using IC 723 Read More »
IC 723 Voltage Regulator: The popular general purpose precision regulator is IC 723. It is a monolithic linear integrated circuit in different physical packages. The pin diagram of IC 723 Voltage Regulator along with the various packages is shown in the Fig. 2.109 (a), (b) and (c). Features of IC 723: It works as voltage
IC 723 Voltage Regulator Read More »
Astable Multivibrator Using IC 555: Fig. 2.105 shows the operation of Astable Multivibrator using 555 Timer IC. The threshold input is connected to the trigger input. Two external resistances RA, RB and a capacitor C is used in the circuit. This circuit has no stable state. The circuits changes its state alternately. Hence the operation
Astable Multivibrator using 555 Timer IC Read More »
Monostable Multivibrator Using IC 555: The IC 555 timer can be operated as a Monostable Multivibrator Using IC 555 by connecting an external resistor and a capacitor as shown in the Fig. 2.102. The circuit has only one stable state. When trigger is applied, it produces a pulse at the output and returns back to
Monostable Multivibrator Using IC 555 Read More »
