UCC3804N - English Editing Encyclopedia Entry

Product Overview

Category

UCC3804N belongs to the category of integrated circuits (ICs) specifically designed for power management applications.

Use

This IC is commonly used in various power supply systems, including switch-mode power supplies (SMPS), battery chargers, and DC-DC converters.

Characteristics

• UCC3804N is a high-performance voltage mode pulse width modulation (PWM) controller.
• It operates with a wide input voltage range, making it suitable for different power supply designs.
• The IC offers precise control over the output voltage and current, ensuring stable and efficient power delivery.
• It incorporates various protection features such as overvoltage protection (OVP), undervoltage lockout (UVLO), and thermal shutdown.

Package and Quantity

UCC3804N is available in a standard 8-pin dual in-line package (DIP). It is typically sold in reels or tubes containing multiple units.

Specifications

• Input Voltage Range: 10V to 30V
• Output Voltage Range: 0V to Vcc
• Maximum Operating Frequency: 1MHz
• Operating Temperature Range: -40°C to +85°C
• Supply Current: 5mA (typical)

Pin Configuration

The UCC3804N IC has the following pin configuration:

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| | --| 1 8 |-- --| 2 7 |-- --| 3 6 |-- --| 4 5 |-- |___________| ```

1. COMP: Compensation pin for feedback loop control.
2. RT/CT: Timing resistor/capacitor connection for setting the oscillator frequency.
3. GND: Ground reference for the IC.
4. VREF: Reference voltage output for external components.
5. VCC: Positive supply voltage input.
6. OUT: Output pin for driving external power devices.
7. FB: Feedback pin for regulating the output voltage.
8. CS: Current sense pin for monitoring the load current.

Functional Features

• Voltage Mode PWM Control: UCC3804N utilizes a voltage mode control scheme to regulate the output voltage accurately.
• Adjustable Oscillator Frequency: The timing resistor and capacitor connected to the RT/CT pin allow users to set the operating frequency according to their requirements.
• Protection Mechanisms: The IC incorporates various protection features such as overvoltage protection, undervoltage lockout, and thermal shutdown to ensure safe operation and prevent damage to the system.
• Soft Start Function: UCC3804N includes a soft start feature that gradually ramps up the output voltage during startup, reducing stress on the power components.

Advantages and Disadvantages

Advantages

• High-performance voltage mode control ensures precise regulation of output voltage and current.
• Wide input voltage range allows flexibility in power supply designs.
• Incorporation of protection mechanisms enhances system reliability and safety.
• Soft start function reduces stress on power components during startup.

Disadvantages

• Limited maximum operating frequency may not be suitable for applications requiring very high switching speeds.
• Availability only in DIP package may limit compatibility with certain modern surface mount technologies.

Working Principles

UCC3804N operates based on the voltage mode control technique. It compares the feedback voltage (FB) with a reference voltage (VREF) to generate an error signal. This error signal is then processed by the internal oscillator, which generates a pulse width modulation (PWM) signal. The PWM signal controls the duty cycle of the output waveform, regulating the output voltage accordingly.

The IC continuously monitors the output voltage and adjusts the duty cycle to maintain the desired voltage level. It also incorporates protection mechanisms such as overvoltage protection, undervoltage lockout, and thermal shutdown to safeguard the system from potential faults or failures.

Detailed Application Field Plans

UCC3804N finds extensive application in various power supply systems, including: 1. Switch-mode power supplies (SMPS) for computers, telecommunication equipment, and industrial machinery. 2. Battery chargers for electric vehicles, portable electronics, and renewable energy systems. 3. DC-DC converters used in automotive electronics, aerospace applications, and telecommunications infrastructure.

The IC's precise control over output voltage and current, along with its protection features, make it suitable for demanding applications where stable and efficient power delivery is crucial.

Detailed and Complete Alternative Models

1. UC3844: A similar voltage mode PWM controller with a higher maximum operating frequency of 500kHz.
2. LM5039: A versatile pulse width modulation controller designed specifically for high-voltage applications.
3. IR2153: An integrated half-bridge driver IC with built-in PWM control and protection features.

These alternative models offer similar functionality to UCC3804