Overview
The UCC28631DR, produced by Texas Instruments, is a high-power flyback controller designed for primary-side regulation (PSR) with peak power mode. This device is part of the UCC2863x family, which offers advanced features for high-efficiency and reliable power conversion. The UCC28631DR operates in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM), ensuring flexible and efficient operation across various load conditions. It eliminates the need for a secondary-side reference, error amplifier, and opto-isolator by using magnetically-sensed output voltage regulation via the transformer bias winding.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Start-up pin voltage (HV) | - | - | 700 | V |
| Bias supply voltage (VDD) | - | - | 20 | V |
| Operating junction temperature range (TJ) | -40 | - | 125 | °C |
| Storage temperature (Tstg) | -65 | - | 125 | °C |
| Lead temperature | - | - | 260 | °C |
| Supply current during normal operation (IDD(run)) | 6.0 | 9.0 | 13.0 | mA |
| Supply current during sleep mode (IDD(sleep)) | 90 | 110 | - | μA |
| Maximum switching frequency (fSW(max)) | 110 | 120 | 130 | kHz |
| Minimum switching frequency (fSW(min)) | 0.18 | 0.20 | 0.22 | kHz |
| Maximum Duty Cycle (DMAX) | - | - | 70% | - |
Key Features
- High-power, primary-side CV/CC regulation
- Operation in both Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM)
- Built-in 700-V start-up current source
- Active X-Capacitor Discharge (except for UCC28631)
- Adjustable Constant-Current (CC) Mode Limiting (except for UCC28630)
- High gate drive current: 1-A source and 2-A sink
- Low power modes for <30-mW system standby
- Best-in-class light load (10%) efficiency >85%
- PSR design with no opto-coupler, meeting high CM isolation & surge requirements
- VDD OVP for independent indirect output OVP under open-feedback fault conditions
- Peak-Power Mode for transient overload
- Shutdown Pin Interface for external NTC
- Protections: Overvoltage, Overcurrent, Over-Temperature, Overload Timer, AC Line UV, Brownout, and Pin Protections
- Frequency Dither to ease EMI compliance (except UCC28632)
Applications
The UCC28631DR is designed for a variety of applications, including:
- AC-DC Adapters for Notebooks and other portable devices
- Power supplies for consumer electronics and appliances
- Industrial power supplies requiring high efficiency and reliability
- Medical devices and equipment
- Telecommunication equipment
The device is particularly suited for designs that require high power efficiency, low standby power, and robust protection features.
Q & A
- What is the primary function of the UCC28631DR?
The UCC28631DR is a high-power flyback controller designed for primary-side regulation (PSR) with peak power mode.
- In which modes can the UCC28631DR operate?
The device operates in both Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM).
- What is the maximum start-up pin voltage for the UCC28631DR?
The maximum start-up pin voltage (HV) is 700 V.
- Does the UCC28631DR have built-in protection features?
Yes, it includes protections such as Overvoltage, Overcurrent, Over-Temperature, Overload Timer, AC Line UV, Brownout, and Pin Protections.
- What is the typical supply current during normal operation?
The typical supply current during normal operation (IDD(run)) is 9.0 mA.
- What is the maximum duty cycle for the UCC28631DR?
The maximum duty cycle (DMAX) is 70%.
- Does the UCC28631DR support frequency dithering for EMI compliance?
Yes, it supports frequency dithering to ease EMI compliance, except for the UCC28632 variant.
- What are the typical applications for the UCC28631DR?
Typical applications include AC-DC adapters for notebooks, power supplies for consumer electronics, industrial power supplies, medical devices, and telecommunication equipment.
- How does the UCC28631DR achieve output voltage regulation?
The device achieves output voltage regulation through magnetically-sensed output voltage regulation via the transformer bias winding, eliminating the need for a secondary-side reference, error amplifier, and opto-isolator.
- What is the operating junction temperature range for the UCC28631DR?
The operating junction temperature range is from -40°C to 125°C.
