Overview
The MC33067DWR2G is a high-performance zero voltage switch resonant mode controller designed by Onsemi. This integrated circuit is optimized for off-line and DC-to-DC converter applications that utilize frequency modulated constant off-time or constant deadtime control. It features a variable frequency oscillator, a precise retriggerable one-shot timer, a temperature-compensated reference, a high gain wide bandwidth error amplifier, and dual high current totem pole outputs suitable for driving power MOSFETs. The device also includes protective features such as a high-speed fault comparator and latch, programmable soft-start circuitry, input undervoltage lockout with selectable thresholds, and reference undervoltage lockout. The MC33067DWR2G is available in surface mount packages, specifically the SOIC-16W package.
Key Specifications
| Characteristic | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Power Supply Voltage | VCC | 20 | V | ||
| Drive Output Current, Continuous | IO | 0.3 | 1.5 | A | |
| Drive Output Current, Pulsed (0.5 μs), 25% Duty Cycle | IO | 0.3 | 1.5 | A | |
| Error Amplifier, Fault, One-Shot, Oscillator and Soft-Start Inputs | Vin | -1.0 | 6.0 | V | |
| UVLO Adjust Input | Vin(UVLO) | -1.0 | VCC | V | |
| Operating Junction Temperature | TJ | 150 | °C | ||
| Operating Ambient Temperature | TA | -40 | 85 | °C | |
| Reference Output Voltage (IO = 0 mA, TJ = 25°C) | Vref | 4.9 | 5.1 | 5.3 | V |
| Reference Undervoltage Lockout Threshold | Vth | 3.8 | 4.3 | 4.8 | V |
Key Features
- Zero Voltage Switch Resonant Mode Operation
- Variable Frequency Oscillator with a Control Range Exceeding 1000:1
- Precision One-Shot Timer for Controlled Off-Time
- Internally Trimmed Bandgap Reference
- High Gain Wide Bandwidth Error Amplifier
- Dual High Current Totem Pole Outputs
- Selectable Undervoltage Lockout Thresholds with Hysteresis
- Enable Input
- Programmable Soft-Start Circuitry
- Low Startup Current for Off-Line Operation
- High-Speed Fault Comparator and Latch
Applications
The MC33067DWR2G is specifically designed for zero voltage switching (ZVS) quasi-resonant converter (QRC) applications. It is optimized for double-ended push-pull or bridge type converters operating in continuous conduction mode. These controllers are ideal for applications requiring high efficiency, lower switching losses, lower EMI emission, and smaller size. Typical applications include DC-to-DC converters, off-line power supplies, and other resonant mode power supply designs.
Q & A
- What is the primary function of the MC33067DWR2G?
The primary function is to provide a fixed off-time to the gates of external power MOSFETs at a repetition rate regulated by a feedback control loop.
- What type of oscillator does the MC33067DWR2G feature?
The device features a variable frequency oscillator with a control range exceeding 1000:1.
- What protective features are included in the MC33067DWR2G?
Protective features include a high-speed fault comparator and latch, programmable soft-start circuitry, input undervoltage lockout with selectable thresholds, and reference undervoltage lockout.
- What is the operating ambient temperature range for the MC33067DWR2G?
The operating ambient temperature range is -40°C to +85°C.
- What is the maximum power supply voltage for the MC33067DWR2G?
The maximum power supply voltage is 20 V.
- What type of packages are available for the MC33067DWR2G?
The device is available in surface mount packages, specifically the SOIC-16W package.
- What is the reference output voltage range for the MC33067DWR2G?
The reference output voltage range is 4.9 V to 5.3 V.
- Does the MC33067DWR2G support programmable soft-start?
Yes, the device supports programmable soft-start circuitry.
- What is the purpose of the undervoltage lockout feature in the MC33067DWR2G?
The undervoltage lockout feature ensures that the device operates only when the input voltage and reference voltage are within safe thresholds, preventing malfunction or damage.
- What are the typical applications for the MC33067DWR2G?
Typical applications include DC-to-DC converters, off-line power supplies, and other resonant mode power supply designs.
