Overview
The MC34067DWR2G is a high-performance zero voltage switch resonant mode controller designed by onsemi for off-line and DC-to-DC converter applications. This integrated circuit utilizes frequency modulated constant off-time or constant deadtime control, making it ideal for various power supply designs. The device 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. Additional protective features include a high-speed fault comparator and latch, programmable soft-start circuitry, input undervoltage lockout with selectable thresholds, and reference undervoltage lockout.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Power Supply Voltage (VCC) | 20 | V |
| Drive Output Current (Continuous) | 0.3 / 1.5 | A |
| Drive Output Current (Pulsed, 0.5 μs, 25% Duty Cycle) | 0.3 / 1.5 | A |
| Reference Output Voltage (Vref) | 5.0 - 5.2 | V |
| Operating Junction Temperature (TJ) | -40 to +150 | °C |
| Operating Ambient Temperature (TA) | -40 to +85 | °C |
| Storage Temperature (Tstg) | -55 to +150 | °C |
| Oscillator Frequency (Error Amp Output Low) | 490 - 550 | kHz |
| Oscillator Frequency (Error Amp Output High) | 1850 - 2200 | kHz |
| Package Type | SOIC-16W | |
| ESD Capability (HBM Model) | 2.0 kV |
Key Features
- Zero Voltage Switch Resonant Mode Operation
- Variable Frequency Oscillator with a control range exceeding 1000:1
- Precision Retriggerable One-Shot Timer for Controlled Off-Time
- Internally Trimmed Bandgap Reference
- 4.0 MHz 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
- Pb-Free Packages Available
Applications
The MC34067DWR2G is designed for use in off-line and DC-to-DC converter applications, particularly those requiring high efficiency and low EMI emission. It is suitable for various power supply designs, including:
- Resonant Mode Power Supplies
- Zero Voltage Switching (ZVS) Applications
- High-Frequency Power Conversion Systems
- Power MOSFET Drivers
Q & A
- What is the primary function of the MC34067DWR2G?
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 are the key protective features of the MC34067DWR2G?
The key 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 temperature range for the MC34067DWR2G?
The operating ambient temperature range is -40°C to +85°C.
- What types of packages are available for the MC34067DWR2G?
The device is available in SOIC-16W and PDIP-16 packages.
- What is the maximum power supply voltage for the MC34067DWR2G?
The maximum power supply voltage (VCC) is 20 V.
- What is the typical oscillator frequency range for the MC34067DWR2G?
The oscillator frequency ranges from 490 kHz to 2200 kHz depending on the error amplifier output state.
- Does the MC34067DWR2G support Pb-free packaging?
- What is the purpose of the one-shot timer in the MC34067DWR2G?
The one-shot timer is used to control the off-time of the power MOSFETs.
- How does the MC34067DWR2G handle system startup and fault conditions?
The device ensures safe and controlled system startup and fault conditions through its programmable soft-start circuitry and high-speed fault comparator and latch.
- What is the significance of the variable frequency oscillator in the MC34067DWR2G?
The variable frequency oscillator allows for a control range exceeding 1000:1, which is crucial for resonant mode power supply applications.
