The three-terminal regulator power supply board can convert various AC or DC input voltages within specified ranges to a stable DC output (fixed) voltage of 5V, 6V, 9V, 12V, or 15V, depending on the selected LM78xx series regulator chip. This module is useful for electronics projects requiring stable low-voltage DC power with a current capacity of up to 1.2A. The built-in power indicator LED shows when the circuit board is receiving input power.
Specification
The quick technical specification of the circuit board is given below.
| Module Type | Power Supply |
| Chip Used | LM7805 /LM7806 /LM7809 /LM7812 /LM7815 |
| Input Type | AC or DC |
| Input Voltage Range | 7V to 24V |
| Input Terminal | 1 |
| Power-ON Indicator | Red Light |
| Output Type | Fixed DC |
| Output Voltage | 5V /6V /9V /12V /15V |
| Output Terminal | 6 |
| Output Current | 1.2 Ampere Max. |
| PCB Colour | Blue |
Circuit Diagram
Schematic of three-terminal regulator power supply module circuit shown below.
The components are used in the circuit boards are - U1: LM78xx IC, D1: 1N4007 Bridge Rectifier, C1: 470uF 50V Electrolytic Capacitor, R1: 1K 0608 SMD Resistor, D1: Red 0608 SMS LED, C2: 100uF 50V Electrolytic Capacitor, C3: 100nF 0608 SMD Ceramic Capacitor, H1 & H2: 2-Pin Screw Terminal, and H3: 5x2 Male Header Pin.
Circuit Working Explanation
The working of the three-terminal power supply circuit is simple. The main components are a bridge rectifier and a voltage regulator chip. This module is commonly available in the market with 5V, 6V, 9V, 12V, and 15V outputs, using the widely used LM78xx series.
When the user applies an AC or DC input voltage (the minimum input should always be at least 2V higher than the output) at terminal H1, the bridge rectifier (D1) converts it to DC. An LED (LED1) and a current-limiting resistor (R1) are connected across the rectifier output to indicate that the circuit is ON. The capacitor (C1) filters the voltage. This voltage is then regulated by the integrated circuit (U1) and smoothed by capacitor (C2). Capacitor (C3) filters out noise, and the regulated output is obtained from terminal H2. Terminal H3 has 10 male header pins, with 5 pins for VCC and 5 pins for GND, used for powering breadboard electronics projects.
0 Comments: