L4977A STMicroelectronics Integrated Circuit (Transistor Outline, Vertical) In Stock
The STMicroelectronics L4977A is a voltage-mode PWM switching regulator controller operating from 15V to 50V input with a nominal 35V operating voltage. It supports single-function control in a 15-pin Power Pack package. In stock worldwide with competitive pricing and fast global shipping.
- Manufacturer
- STMicroelectronics
- Package
- Transistor Outline, Vertical
- Pin Count
- 15
- Lifecycle
- OBSOLETE
- Datasheet
- L4977A Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- -40.0°C to 150.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Voltage-mode PWM control with 15V to 50V input range enabling flexible offline and DC-DC converter designs
- Single-function switching regulator controller with pulse width modulation for precise output voltage regulation
- 15-pin Power Pack package provides robust power handling and thermal performance for high-current applications
- Wide input voltage range (15V to 50V) accommodates unregulated DC bus variations in industrial power supplies
Applications
The L4977A is used as a PWM controller in voltage-mode regulated DC-DC power supplies and offline switching converters where input voltages range from 15V to 50V. Its single-function architecture simplifies the design of forward converters, flyback power supplies, and buck regulators for industrial equipment and power distribution systems. The device is also suitable for battery chargers and motor controller power stages operating from rectified AC or high-voltage DC bus inputs.
Specifications
| YTEOL | 0 |
| Analog IC - Other Type | SWITCHING REGULATOR |
| Control Mode | VOLTAGE-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 50V |
| Input Voltage-Min | 15V |
| Input Voltage-Nom | 35V |
| JESD-30 Code | R-PZFM-T15 |
| JESD-609 Code | e3 |
| Number of Functions | 1 |
| Output Current-Max | 11A |
| Output Voltage-Max | 40V |
| Output Voltage-Min | 5.1V |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | ZIP15,.2,.17TB |
| Package Shape | RECTANGULAR |
| Package Style | FLANGE MOUNT |
| Qualification Status | Not Qualified |
| Surface Mount | NO |
| Switcher Configuration | BUCK |
| Switching Frequency-Max | 500kHz |
| Technology | BCDMOS |
| Terminal Finish | MATTE TIN |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 1.27mm |
| Terminal Position | ZIG-ZAG |
| Package | Transistor Outline, Vertical |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What is the input voltage range of the L4977A?
The L4977A operates with an input voltage ranging from 15V minimum to 50V maximum, with a nominal operating voltage of 35V. This wide input range makes it suitable for power supply designs that must accommodate unregulated DC bus voltages derived from rectified AC mains or high-voltage battery systems in industrial applications.
What control mode does the L4977A use?
The L4977A uses voltage-mode PWM (Pulse Width Modulation) control. In voltage-mode control, the output voltage is sensed and compared to a reference, and the duty cycle of the switching waveform is adjusted accordingly to regulate the output. This approach provides stable regulation in many standard converter topologies including buck, forward, and flyback converters.
What package does the L4977A come in?
The L4977A is housed in a 15-pin Power Pack (PZFM-T15) package. This through-hole power package is designed for high thermal dissipation and can be mounted to a heatsink, making it suitable for switching regulator applications where the controller handles significant power levels or operates in high-ambient-temperature environments.
What types of power supply topologies can the L4977A control?
The L4977A is designed for use in voltage-mode PWM switching power supplies including buck (step-down) converters, forward converters, and flyback isolated power supplies. Its wide 15V to 50V input range and PWM control architecture make it compatible with offline AC-DC adapter stages, DC-DC converters in industrial equipment, and battery-input power systems.
Is the L4977A still in production?
The L4977A has a YTEOL (Years to End of Life) value of 0, which indicates it is at or near end-of-life status from STMicroelectronics. Designers starting new projects should evaluate modern replacement PWM controller ICs from STMicroelectronics such as the L6565 or L6566 series. However, the L4977A may still be available from distributors for maintenance of existing designs.
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About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
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