Overview
The L6599AN, produced by STMicroelectronics, is an improved revision of the previous L6599. It is a double-ended controller specifically designed for series-resonant half-bridge topology. This controller provides a 50% complementary duty cycle, where the high-side and low-side switches are driven ON/OFF 180° out-of-phase for exactly the same time. This configuration enables soft-switching and high-frequency operation, making it suitable for various high-efficiency power supply applications.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Frequency | Up to 500 kHz | |
| Supply Voltage (Vcc) | 8.85 to 16 V | V |
| High-Side Gate Driver Voltage (VBOOT) | -1 to 618 V | V |
| High-Side Gate Driver Current | -300 to 800 mA | mA |
| Low-Side Gate Driver Current | 0.3 A (source), 0.8 A (sink) | A |
| Junction Operating Temperature | -40 to 150 °C | °C |
| Storage Temperature | -55 to 150 °C | °C |
| Thermal Resistance (Junction to Ambient) | 80 °C/W (DIP16), 120 °C/W (SO16) | °C/W |
Key Features
- 50% complementary duty cycle for high-side and low-side switches
- High-accuracy oscillator with variable frequency control
- Two-level overcurrent protection (OCP): frequency-shift and latched shutdown
- Interface with PFC controller for pre-regulator control during fault conditions
- Latched disable input for easy implementation of OTP and/or OVP
- Burst mode operation at light load for reduced quiescent current
- Input for power-ON/OFF sequencing or brownout protection
- Non-linear soft-start for monotonic output voltage rise
- 600 V-rail compatible high-side gate driver with integrated bootstrap diode and high dV/dt immunity
Applications
- LCD and PDP TVs
- Desktop PCs and entry-level servers
- Telecom SMPS (Switch-Mode Power Supplies)
- High-efficiency industrial SMPS
- AC-DC adapters and open frame SMPS
Q & A
- What is the primary function of the L6599AN?
The L6599AN is a double-ended controller for series-resonant half-bridge topology, providing 50% complementary duty cycle for high-side and low-side switches.
- What is the maximum operating frequency of the L6599AN?
The L6599AN can operate up to 500 kHz.
- What types of overcurrent protection does the L6599AN offer?
The L6599AN offers two-level overcurrent protection: frequency-shift and latched shutdown.
- How does the L6599AN handle burst mode operation?
The L6599AN enters burst mode operation at light load, reducing quiescent current. This is achieved through the STBY pin sensing a voltage related to the feedback control.
- What is the purpose of the RFmin pin on the L6599AN?
The RFmin pin sets the minimum oscillator frequency and is used to regulate the converter output voltage by modulating the oscillator frequency.
- What is the thermal resistance of the L6599AN in DIP16 and SO16 packages?
The thermal resistance is 80 °C/W for DIP16 and 120 °C/W for SO16 packages.
- How does the L6599AN protect against short circuits and overloads?
The L6599AN protects against short circuits and overloads through a combination of frequency-shift and latched shutdown overcurrent protection mechanisms.
- Can the L6599AN be used with PFC controllers?
Yes, the L6599AN has an interface with PFC controllers to enable the pre-regulator to be switched off during fault conditions.
- What are the typical applications of the L6599AN?
The L6599AN is typically used in LCD and PDP TVs, desktop PCs, telecom SMPS, high-efficiency industrial SMPS, and AC-DC adapters.
- How does the L6599AN handle soft-start and power sequencing?
The L6599AN features a non-linear soft-start for monotonic output voltage rise and has inputs for power-ON/OFF sequencing or brownout protection.
