L7915CP

The L7915CP voltage regulator is an adjustable three-terminal negative regulator integrated circuit. It consists of a power transistor, an internal voltage reference, a sense resistor, and current-limiting circuitry. This type of voltage regulator is one of two popular types of voltage regulators - linear and switched-mode. Linear voltage regulators, like the L7915CP, maintain a constant output voltage regardless of varying output load currents or input voltage changes. This type of voltage regulator works by controlling one of the terminals, usually the gate of a power transistor. When the input voltage rises, the runtime of the gate is increased and more current is allowed from the input to the output. In this way, the output voltage of the voltage regulator remains steady despite the changing input voltage.

The L7915CP voltage regulator is designed to provide a fixed negative output voltage of 15V. Output voltage can be adjusted by changing the adjustment terminal voltage from -0.3V to -13.2V, plus an external resistor divider. The device is available in three package types, TO-220, SOT 89, and SIP-3, and can operate in temperatures ranging from - 40℃ up to + 125℃.

The L7915CP is mainly used in industrial, automotive, and consumer applications including:

• Interfacing between microcontroller and electronics circuits
• Battery-powered equipment
• Automotive electronics, such as audio amplifiers, electronic door locks etc.
• Power converters, power supplies, and battery chargers
• DC motors
• Telecommunications

In terms of its working principle, the L7915CP is designed to be an adjustable three-terminal negative regulator. It comprises of 3 pins- an adjustment pin, an output pin, and an input pin. The adjustment pin is used to set the desired output voltage and the output pin provides a steady 15V negative voltage. The input pin is connected to the input voltage which is then regulated by the L7915CP.

The internal functional blocks of the L7915CP include a temperature limitation circuitry, an error amplifier, a reference voltage source, a power transistor, and two resistors (an internal resistor and a sense resistor). The temperature limited circuitry protects the device at high temperatures, while the error amplifier compares the voltage of the output and the reference. The power transistor passes current according to how the error amplifier adjusts the gate voltage. The sense resistor is used to sense the load current and control the power transistor accordingly.

The L7915CP is an adjustable three-terminal negative linear regulator which is designed to provide a reliable regulated output voltage of 15V with a high precision. It is mainly used for industrial, automotive, and consumer applications and its working principle is based on controlling a power transistor gate to maintain a steady output voltage from varying input voltages.