on December 17th 2,084

Understanding the SG3525 PWM IC

The SG3525 PWM controller is a versatile and precise 16-pin IC widely used in modern power electronics for switched-mode power supplies (SMPS) and PWM signal generation. Known for its efficient design and minimal external components, it ensures reliable performance in power regulation and conversion applications. Its sophisticated feedback control system delivers stable output voltage, serious for precision-demanding systems like renewable energy and industrial circuits, while integrated protection mechanisms safeguard against faults and voltage surges. Supporting inverter configurations like push-pull and DC-DC conversion, the SG3525 offers you precise control over switching intervals and dead time, optimizing efficiency. This article explores its pin configuration, features, applications, and alternatives, highlighting its impact on power electronics design.

Catalog

Pin Configuration

Pin Number	Pin Name	Pin Function
1	INV	Inverting Input
2	NINV	Non-Inverting Input
3	SYNC	Synchronizing IC with an external oscillator frequency.
4	OSC. Output	Oscillator Output. The frequency of IC is confirmed at this pin.
5, 6	CT & RT	Used to connect an external capacitor and resistor, respectively, to set up the oscillator frequency.
7	Discharge (DIS)	Determines the dead time for IC. A resistor between pin-7 and 5 decides the PWM frequency (or dead time).
8	Soft Start (SS)	Connects to a capacitor and ground. Used to initiate operation softly.
9	Compensation (COMP)	Compensation pin. It compensates for errors and avoids rapid fluctuations.
10	Shutdown	Instantly narrows PWM signals to the maximum level if set high. Used to shut down the IC output during malfunctions.
11	Output A	Output pin used as an input for external devices.
12	VSS	Ground pin.
13	VC	Power pin (5-35 V). A resistor connected to the DC supply determines the trigger current magnitude.
14	Output B	Output pin used as an input for external devices.
15	Vin	Supply input voltage (8-35 V).
16	Vref	Reference pin used to set reference voltage through pins 1 and 2.

Features and Technical Specifications

Feature/Specification	Value
Supply Voltage	8V to 35V
Oscillation Range	100 Hz to 400 kHz
Maximum Power Dissipation	1000 mW
Reference Voltage Trim Accuracy	5.1 V (±1%)
Supply Voltage VCC	+40 Vdc
Logic Input Voltage	-0.3 to 5.5 V
Output Current (IO)	±500 mA
Reference Output Current (Iref)	50 mA
Oscillator Charging Current	5 mA
Power Dissipation (PD)	1000 mW
Thermal Resistance (Junction-to-Air, RθJA)	100 ˚C/W
Thermal Resistance (Junction-to-Case, RθJC)	60 ˚C/W
Operating Junction Temperature (TJ)	150 ˚C
Output Drivers	Dual-source/sink
Soft-Start	Internal
Shutdown	Pulse-by-pulse
Dead Time Control	Adjustable
Oscillator Sync Terminal	Separate
PWM Latching	Prevents Multiple Pulses

Alternative Model

• SG2525

• UC3525

Proficient Use of the SG3525 PWM Controller

The adaptable SG3525 PWM controller serves as a remarkable element often utilized in inverter applications due to its reliable performance. This integrated circuit, equipped with dual PWM outputs and a built-in totem pole PWM driver, is well-suited for managing semiconductor devices with currents up to 50 mA, accommodating various engineering needs efficiently.

At its foundation, the SG3525 automates the PWM control process, which plays an active role in the efficient conversion of DC to AC power.

• Its dual outputs facilitate balanced power delivery, improving the conversion process in applications such as solar inverters and motor speed controllers.

• The IC’s design mitigates complex power regulation challenges, streamlining system integration and minimizing the requirement for additional components.

To configure the output frequency of the SG3525, careful manipulation of pins 5, 6, and 7 is needed.

Applications of SG3525

The SG3525 finds its place within DC-DC converter inverters. Its pulse-width modulation characteristics ensure that power is transferred and regulated with exceptional efficiency, akin to the calm assurance of a seasoned guide maintaining stability in tumultuous circumstances. It breathes consistency into power supply systems, providing a sense of security in its ability to ward off the chaos of voltage irregularities that might otherwise disrupt or damage sensitive equipment.

DC-DC Converter Inverters

Within the domain of DC-DC converter inverters, the SG3525 is adept at transforming DC inputs into desirable outputs with remarkable efficiency. You can draw upon its capabilities, notably within renewable energy applications, where the conversion of solar-generated DC power into practical forms feels like harnessing the sun itself to light up new paths of innovation. The device's dynamic form offers a reliable partner in ensuring the optimal use of energy, dancing seamlessly between varied power demands to maintain harmony across diverse ecosystems.

Power Supply Regulation

The SG3525 also steps into the role of power supply regulation with suave competence, delivering a steady rhythm of voltage output that ensures order amidst technological symphonies. Its ability to adeptly handle multiple voltage levels plays a major part in computer hardware, eliminating the stress and crashes of inconsistent power flow. Here, its influence is appreciated in both industrial settings and personal gadgets, where its contribution to smooth operations invites your confidence and satisfaction.

Switching Regulators Across Polarities

SG3525's versatility shines through in its use within switching regulators, fluent across varying polarities. This design accommodates swift responses to ever-changing load conditions, promoting an environment where power efficiency is not just achieved but celebrated. The SG3525 is a trusted ally in crafting systems that balance complexity with simplicity, ensuring that power needs are met with reliability. It's an unspoken promise of adaptability and strength in the face of varying current demands.

2D Model and Measurements