SG3525A 3525 PWM Controller IC DIP-16 – Switching Power Supply & Inverter IC

The SG3525A 3525 PWM Controller IC is a specialized PWM control IC for switching power supply and power inverter applications. It combines an oscillator, error amplifier, PWM comparator, soft-start circuitry, shutdown control, under-voltage lockout, and output drivers into a single DIP-16 package.

The integrated 5.1V precision reference can be used within the control circuit without requiring a separate reference IC. The oscillator provides a configurable switching frequency, while the synchronization input allows the oscillator to be synchronized with another circuit or external clock.

The adjustable dead-time control is particularly useful in push-pull and other switching configurations where controlled timing between output pulses is required. The built-in soft-start function helps control the startup behavior of the PWM system.

The SG3525A is a popular choice for DIY power inverter projects, DC-DC converters, switching power supplies, battery-powered power electronics, and educational experiments involving PWM control.

Features

• SG3525A PWM controller IC
• 16-pin PDIP through-hole package
• Built-in 5.1V precision reference
• Adjustable oscillator frequency
• Separate oscillator synchronization input
• Adjustable dead-time control
• Built-in soft-start circuitry
• Under-voltage lockout
• PWM latch to help prevent multiple pulses
• Shutdown and pulse-by-pulse shutdown capability
• Dual high-current totem-pole output stages
• Suitable for switching power supplies and inverter circuits

Applications

• DC-AC power inverter circuits
• Switching power supplies
• DC-DC converters
• Push-pull converters
• PWM power control
• Battery-powered inverter systems
• SMPS development
• Power electronics experiments
• DIY electronics projects
• Educational power-conversion circuits

How to Use

1. Identify the SG3525A pin configuration before installation.
2. Connect the IC to a suitable DC supply within its specified operating range.
3. Configure the oscillator timing components to obtain the desired PWM frequency.
4. Set the required dead time using the appropriate external resistor configuration.
5. Connect the feedback/error amplifier circuitry according to the desired regulation scheme.
6. Use the output pins to drive suitable external switching transistors or MOSFET driver stages.
7. Add appropriate supply decoupling and protection components around the IC.
8. Test the PWM output at low power before connecting the controller to a high-power inverter or switching stage.

Important Notes

• The 8V–35V operating range is the appropriate supply range stated for normal SG3525A operation; the separately listed 3V/40V values should not be treated as the recommended operating range.
• The SG3525A is a controller IC, not a high-power MOSFET or transistor driver by itself for every application. External driver components may be required depending on the switching device and operating frequency.
• High-power inverter and SMPS circuits can contain dangerous voltages and high currents. Use appropriate protection and electrical safety practices.
• Select dead time, switching frequency, gate-drive components, and power-stage components according to the specific circuit design.
• Use adequate heat dissipation and current protection for external switching devices.
• Verify the IC pinout before powering the circuit.
• Allow up to approximately 5% dimensional variation due to manual measurement.
• Product images are for illustration purposes only and may differ from the actual product.

Package Includes

• 1 × SG3525A 3525 PWM Controller IC