Overview
The UCC28514DW, produced by Texas Instruments, is a member of the UCC28510 series of combination PFC/PWM controllers. These controllers provide comprehensive control functionality for off-line power systems, ensuring compliance with IEC1000-3-2 harmonic reduction requirements. By integrating the control and drive signals for both the Power Factor Correction (PFC) and Pulse Width Modulation (PWM) stages into a single device, the UCC28514DW offers significant performance and cost benefits. It features leading-edge modulation for the PFC stage and trailing-edge modulation for the PWM stage, which minimizes ripple current in the boost capacitor and enhances noise immunity.
Key Specifications
| Parameter | Min | Typ | Max | Units |
|---|---|---|---|---|
| Supply Current (Off) | 100 | 150 | - | µA |
| Supply Current (On, no load) | 4 | 6 | - | mA |
| VCC Turn-On Threshold | 10.2 | - | 10.8 | V |
| VCC Turn-Off Threshold | 9.1 | - | 10.6 | V |
| UVLO Hysteresis | 0.3 | - | 0.8 | V |
| Input Voltage (VSENSE) | 7.35 | 7.50 | 7.65 | V |
| GT1 Output Rise Time (CLOAD = 1 nF) | 16 | - | 25 | ns |
| GT1 Output Fall Time (CLOAD = 1 nF) | 7 | - | 15 | ns |
| PWM Stage Frequency Ratio | 1:2 | - | - | - |
| Operating Temperature Range | -40 | - | 105 | °C |
| Package Type | SOIC (DW) | - | - | - |
Key Features
- Combines control and drive signals for PFC and PWM stages in a single device.
- Leading-edge PFC and trailing-edge PWM modulation to reduce ripple current.
- Average-current-mode control for continuous conduction mode operation in PFC stage.
- Peak-current-mode control operation in PWM stage.
- Programmable maximum duty cycle and soft-start for PWM stage.
- Highly-linear multiplier for near-unity power factor in PFC stage.
- Input voltage feedforward implementation and improved load transient response.
- Accurate power limiting, zero power detect, and overvoltage protection.
- High-current output gate drivers for both PFC and PWM stages.
- UVLO circuit with selectable hysteresis levels.
Applications
The UCC28514DW is suitable for various off-line power systems that require compliance with harmonic reduction standards such as IEC1000-3-2. These include:
- Switch-mode power supplies.
- Power factor correction (PFC) circuits.
- Pulse width modulation (PWM) controllers.
- High-efficiency power conversion systems.
- Industrial power supplies.
- Consumer electronics power systems.
Q & A
- What is the primary function of the UCC28514DW?
The UCC28514DW is a combination PFC/PWM controller designed to provide complete control functionality for off-line power systems, ensuring compliance with harmonic reduction standards.
- What modulation techniques does the UCC28514DW use?
The device uses leading-edge modulation for the PFC stage and trailing-edge modulation for the PWM stage to minimize ripple current in the boost capacitor.
- What are the key features of the PFC stage in the UCC28514DW?
The PFC stage features average-current-mode control, a highly-linear multiplier for near-unity power factor, input voltage feedforward, and improved load transient response.
- What are the key features of the PWM stage in the UCC28514DW?
The PWM stage features peak-current-mode control, programmable maximum duty cycle, programmable soft-start, and high-current output gate drivers.
- What is the operating temperature range of the UCC28514DW?
The device operates over a temperature range of -40°C to 105°C.
- What package types are available for the UCC28514DW?
The UCC28514DW is available in SOIC (DW) packages.
- What is the significance of the UVLO circuit in the UCC28514DW?
The UVLO (Undervoltage Lockout) circuit with selectable hysteresis levels ensures that the device operates within safe voltage ranges and prevents malfunction during voltage drops.
- How does the UCC28514DW manage startup and shutdown sequences?
The device features built-in sequencing of PFC and PWM turn-on and turn-off, ensuring that the PWM stage is suppressed until the PFC output reaches a specified percentage of its programmed value during startup.
- What are some common applications of the UCC28514DW?
The UCC28514DW is used in switch-mode power supplies, PFC circuits, PWM controllers, high-efficiency power conversion systems, industrial power supplies, and consumer electronics power systems.
- How does the UCC28514DW enhance noise immunity?
The device enhances noise immunity through its current amplifier implementation and the use of leading-edge and trailing-edge modulation techniques.
- What is the power dissipation of the UCC28514DW in SOIC (DW) package?
The power dissipation in the SOIC (DW) package is 0.7 W.
