Overview
The FSL138MRTWDTU, produced by onsemi, is an integrated Pulse Width Modulation (PWM) controller and SenseFET designed for offline Switched-Mode Power Supplies (SMPS). This device is part of the Green-Mode Fairchild Power Switch (FPS™) family, optimized for high input voltage applications. It combines a PWM controller with an internal avalanched-rugged 800V SenseFET, reducing the need for external components and enhancing system reliability and efficiency.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| Drain-Source Breakdown Voltage (BVDSS) | 800 | V | ||
| Drain-Source On-State Resistance (RDS(ON)) | 4.0 | 5.0 | Ω | |
| Switching Frequency (fS) | 61 | 67 | 73 | kHz |
| Peak Drain Current Limit (ILIM) | 1.89 | 2.15 | 2.41 | A |
| Operating Junction Temperature | -40 | 125 | °C | |
| Thermal Shutdown Temperature (TSD) | 130 | 140 | 150 | °C |
| Operating Supply Current (IOP) in Burst Mode | 0.3 | 0.4 | 0.5 | mA |
Key Features
- Internal Avalanched-Rugged 800V SenseFET: Provides high voltage handling capability.
- Advanced Soft Burst-Mode Operation: Minimizes power dissipation in standby mode, reducing standby power consumption to under 40mW at 265VAC and no-load condition.
- Random Frequency Fluctuation: Reduces Electromagnetic Interference (EMI).
- Pulse-by-Pulse Current Limit: Ensures safe operation by limiting peak current.
- Various Protection Functions: Includes Overload Protection (OLP), Over-Voltage Protection (OVP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD) with hysteresis, and Under-Voltage Lockout (UVLO) with hysteresis.
- Low Operating Current in Burst Mode: Only 0.4mA, enhancing efficiency.
- Internal Startup Circuit and Built-in Soft-Start: Simplifies startup and ensures smooth operation with a typical soft-start time of 15ms.
- Auto-Restart Mode: Automatically restarts the device after a fault condition is resolved.
Applications
The FSL138MRTWDTU is suitable for various power supply applications, including:
- Power supplies for set-top boxes (STB) and home appliances.
- Industrial power supplies with high AC input voltage.
- Cost-effective design of flyback converters.
Q & A
- What is the primary function of the FSL138MRTWDTU?
The FSL138MRTWDTU is an integrated PWM controller and SenseFET designed for offline Switched-Mode Power Supplies (SMPS).
- What is the maximum drain-source breakdown voltage of the FSL138MRTWDTU?
The maximum drain-source breakdown voltage is 800V.
- How does the FSL138MRTWDTU reduce EMI?
The device uses random frequency fluctuation to reduce Electromagnetic Interference (EMI).
- What are the key protection functions of the FSL138MRTWDTU?
The device includes Overload Protection (OLP), Over-Voltage Protection (OVP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD) with hysteresis, and Under-Voltage Lockout (UVLO) with hysteresis.
- What is the typical standby power consumption of the FSL138MRTWDTU?
The typical standby power consumption is under 40mW at 265VAC and no-load condition.
- How does the FSL138MRTWDTU handle startup?
The device has an internal startup circuit and a built-in soft-start feature with a typical soft-start time of 15ms.
- What is the operating junction temperature range of the FSL138MRTWDTU?
The operating junction temperature range is from -40°C to 125°C.
- What is the thermal shutdown temperature of the FSL138MRTWDTU?
The thermal shutdown temperature is between 130°C and 150°C.
- How does the FSL138MRTWDTU operate in low load conditions?
The device enters Burst-Mode operation to minimize power dissipation in standby mode.
- What are the typical applications of the FSL138MRTWDTU?
The device is used in power supplies for set-top boxes, home appliances, and industrial applications with high AC input voltage.
