Overview
The STSR2PCD-TR is a smart driver IC designed by STMicroelectronics to drive secondary synchronous rectifiers in medium power, low output voltage, high efficiency forward converters. This IC is part of the STSR2P/STSR2PM family and is packaged in an SO-8 format. It provides two complementary high current outputs to drive power MOSFETs, ensuring proper timing and preventing secondary side shoot-through conditions. The IC operates independently from the forward magnetic reset technique and supports discontinuous conduction mode, making it versatile for various power conversion applications.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| VCC (DC Input Voltage) | -0.3 | 6 | V | |
| VOUTGATE (Max Gate Drive Output Voltage) | -0.3 | VCC | V | |
| VINHIBIT (Max INHIBIT Voltage) | -0.6 | VCC | V | |
| VCK (Clock Input Voltage Range) | -0.3 | VCC | V | |
| ILX (Switching Peak Current) | 2 | A | ||
| PTOT (Continuous Power Dissipation at TA=105°C without heatsink) | 270 | mW | ||
| Tstg (Storage Temperature Range) | -55 | 150 | °C | |
| Tj (Top Operating Junction Temperature Range) | -40 | 125 | °C | |
| Rthj-amb (Thermal Resistance Junction-ambient) | 160 | °C/W | ||
| ICC (Unloaded Supply Current) | 22 | 30 | mA | |
| VOH (Output High Voltage) | 4.70 | 4.85 | V | |
| VOL (Output Low Voltage) | 0.10 | 0.16 | V | |
| tR (Rise Time) | 40 | ns | ||
| tF (Fall Time) | 30 | ns |
Key Features
- Complementary High Current Outputs: The STSR2PCD-TR provides two high current outputs to drive power MOSFETs, with a source peak current of 2A and a sink peak current of 3.5A.
- Smart Turn-off Anticipation Timing: The IC features a fast cycle-after-cycle control logic mechanism that ensures proper timing at the outputs' turn-off transition, preventing shoot-through conditions.
- Independent Operation from Forward Magnetic Reset Technique: The IC's operation is independent of the forward magnetic reset technique, avoiding common problems associated with self-driven synchronous rectifiers.
- Discontinuous Conduction Mode Support: The IC includes an Inhibit function that allows the shut-off of OUTGATE2, enabling discontinuous conduction mode and protecting the converter from sinking current from the load.
- Under Voltage Lock Out (UVLO): Ensures proper start-up and avoids undesirable driving during supply voltage drops.
- High Frequency Oscillator: An internal 15MHz oscillator synchronized by the clock signal provides precise control over the outputs.
Applications
The STSR2PCD-TR is designed for use in medium power, low output voltage, high efficiency forward converters. It is particularly suitable for applications such as:
- DC-DC converters in power supplies.
- Secondary synchronous rectification in forward converters.
- High efficiency power conversion systems.
- Discontinuous conduction mode operations.
Q & A
- What is the supply voltage range for the STSR2PCD-TR?
The supply voltage range is from 4.5V to 5.5V.
- What are the peak output currents for the STSR2PCD-TR?
The source peak current is 2A, and the sink peak current is 3.5A.
- How does the STSR2PCD-TR prevent shoot-through conditions?
The IC features a smart internal control logic mechanism with turn-off anticipation timing to prevent shoot-through conditions.
- Can the STSR2PCD-TR operate in discontinuous conduction mode?
Yes, the IC includes an Inhibit function that allows the shut-off of OUTGATE2, enabling discontinuous conduction mode.
- What is the thermal resistance junction-ambient for the STSR2PCD-TR?
The thermal resistance junction-ambient is 160 °C/W.
- What is the typical unloaded supply current for the STSR2PCD-TR?
The typical unloaded supply current is 30 mA.
- How does the STSR2PCD-TR protect against under-voltage conditions?
The IC features an Under Voltage Lock Out (UVLO) to ensure proper start-up and avoid undesirable driving during supply voltage drops.
- What is the operating frequency range for the STSR2PCD-TR?
The operating frequency range is from 20 kHz to 750 kHz.
- How is the anticipation time for OUTGATE2 set?
The anticipation time for OUTGATE2 can be set through external components by partitioning the supply voltage.
- What are the typical rise and fall times for the STSR2PCD-TR?
The typical rise time is 40 ns, and the typical fall time is 30 ns.
