Microchip Technology SG2524N

Overview

SG2524N from Microchip Technology is a monolithic PWM controller IC designed for regulating power supply inverters and switching regulators. It integrates voltage reference, error amplifier, oscillator (100 Hz–300 kHz), pulse-width modulator, dual alternating output switches (50 mA each), and current-limiting/shutdown circuitry in a 16-pin plastic DIP package. It supports single-ended or push-pull topologies in DC-DC converters, polarity converters, and transformer-coupled applications.

For engineers reviewing the SG2524N datasheet, SG2524N pinout, SG2524N application, or SG2524N equivalent, this page delivers verified functional identity, ambient temperature range (–25 °C to +85 °C), oscillator frequency limits, dual-transistor output capability, and current-sense interface details critical for power supply design validation and replacement selection.

Technical Context

The SG2524N implements a fixed-frequency PWM architecture with an internal flip-flop that alternates drive between two NPN output transistors, enabling push-pull operation at half the oscillator frequency. Its oscillator uses external RT/CT components to generate a linear sawtooth waveform (0.6–3.8 V peak-to-valley) for precise duty-cycle control.

Current limiting is implemented via dedicated sense pins (Pin 4 and Pin 5) with a nominal 200 mV threshold and ±0.3 V common-mode range, requiring ground-referenced sensing. The error amplifier features 72 dB open-loop gain, 1 MHz gain-bandwidth product, and 70 dB common-mode rejection-enabling stable feedback loop compensation in isolated and non-isolated topologies.

Key Specifications

Pinout & Package

SG2524N is housed in a 16-pin plastic dual-in-line (N-package) with 0.3-inch row spacing and standard through-hole mounting. Thermal resistance is θJA = 65 °C/W (plastic DIP), suitable for natural-convection PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PWM controller applications.

Compared with UC3524N and TL494CN, the SG2524N offers guaranteed industrial temperature operation, integrated current-limit amplifier with 200 mV threshold, and tighter reference regulation-making it optimal for ruggedized power supplies where reliability under thermal stress and simplified current protection are design priorities.

Availability

SG2524N is available at Aetrix Electronics and suitable for industrial DC-DC converters, transformer-coupled inverters, and programmable polarity converters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SG2524N includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology is a global provider of microcontrollers, analog devices, and power management ICs, with emphasis on embedded control and industrial reliability.

The SG2524N belongs to Microchip's legacy PWM controller product line, designed specifically for discrete-switch-based switching power supplies requiring integrated oscillator, error amplifier, and dual-output drive in a single monolithic IC.

FAQ

What is the maximum allowable oscillator frequency for SG2524N?

The SG2524N supports oscillator frequencies from 100 Hz up to 300 kHz, as confirmed in Table 3-1 of the official datasheet. This upper limit is achievable with appropriate RT/CT values-for example, RT = 2 kΩ and CT = 1 nF yields up to 400 kHz typical, but the guaranteed operational maximum remains 300 kHz across the full –25 °C to +85 °C ambient range. Exceeding 300 kHz may compromise duty-cycle linearity and current-limit response time.

Can SG2524N be used in push-pull topology without external logic?

Yes, the SG2524N can drive push-pull topologies directly without external logic. Its internal flip-flop alternates conduction between OUT A and OUT B, ensuring inherent dead-time and preventing shoot-through. When configured for push-pull, the effective transformer switching frequency is half the oscillator frequency-e.g., 100 kHz oscillator yields 50 kHz primary-side switching-making SG2524N suitable for forward and push-pull DC-DC converters.

What is the purpose of Pin 15 (V–) on SG2524N?

Pin 15 (V–) on the SG2524N is the negative supply terminal for dual-supply operation. However, the device is fully functional in single-supply mode when V– is tied to GND (Pin 8). It is not used in standard applications and must remain connected to ground unless implementing specialized bipolar supply configurations-per datasheet Section 6, "Connection Diagrams and Ordering Information," V– is internally referenced to GND in all recommended operating conditions.

How does the current limit function work on SG2524N?

The SG2524N implements current limiting via dedicated CL+ (Pin 4) and CL– (Pin 5) inputs with a nominal 200 mV threshold. The internal amplifier compares the differential voltage across a ground-referenced sense resistor and reduces PWM duty cycle when exceeded. Its ±0.3 V common-mode range mandates sensing in the return path, and source impedance must stay below 50 Ω to hold threshold error under 5%, as detailed in Application Note 5.2.

Is SG2524N RoHS compliant?

Yes, the SG2524N in the N-package is RoHS compliant and features 100% matte tin lead finish, as stated in Table 6-1 ("Connection Diagrams and Ordering Information") of the datasheet. The RoHS/Pb-free transition date for the N-package is documented as DC: 05034, confirming full compliance with EU Directive 2011/65/EU and related amendments.