Overview
The LT8638SEV#PBF is a 42V, 10A (12A peak) synchronous step-down regulator from Analog Devices, featuring the second-generation Silent Switcher architecture. This regulator is designed to minimize EMI emissions while delivering high efficiency and high speed. It is particularly suited for noise-sensitive applications due to its ultralow emission characteristics and selectable spread spectrum mode. The device is available in a compact 5mm x 4mm LQFN package with exposed pads for low thermal resistance, making it ideal for a variety of applications including automotive and industrial systems.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Units |
|---|---|---|---|---|---|
| Minimum Input Voltage | fSW = 2MHz | 2.6 | 2.8 | V | |
| Quiescent Current in Shutdown | VEN/UV = 0V, VIN = 12V | 6 | 9 | µA | |
| Quiescent Current in Sleep | VEN/UV = 2V, VFB > 0.6V, VSYNC = 0V, VBIAS = 0V | 125 | 195 | 245 | µA |
| Output Current | 10 | 12 (peak) | A | ||
| Operating Temperature Range | -40°C | 125°C / 150°C (automotive grade) | °C | ||
| Switching Frequency | Up to 2MHz | Hz |
Key Features
- Low EMI Emissions: The LT8638SEV#PBF features the second-generation Silent Switcher architecture, which minimizes EMI emissions, making it suitable for noise-sensitive applications.
- High Efficiency and Speed: The regulator offers high efficiency and high-speed operation, with a minimum on-time as small as 25ns, allowing for high step-down conversion even at high frequencies.
- Selectable Operating Modes: The device supports various operating modes including Burst Mode, Forced Continuous Mode (FCM), and spread spectrum mode, which can be configured using the SYNC/MODE pin.
- Integrated Bypass Capacitors: The regulator includes integrated bypass capacitors that optimize fast current loops and reduce layout sensitivity, further minimizing EMI emissions.
- Compact Package: The device is packaged in a 5mm x 4mm LQFN package with exposed pads for low thermal resistance.
- Soft-Start and Tracking: The SS pin allows user control of the output voltage ramp rate during start-up, enabling soft-start and tracking functionalities.
Applications
- Automotive Systems: The LT8638SEV#PBF is available in automotive-grade versions, making it suitable for use in automotive applications such as battery-powered systems and infotainment systems.
- Industrial Supplies: The wide input range (3.9V to 42V) makes it compatible with various industrial power supplies and battery configurations.
- Noise-Sensitive Applications: The regulator's low EMI emissions and spread spectrum mode make it an ideal choice for noise-sensitive applications such as medical devices, communication equipment, and other high-reliability systems.
Q & A
- What is the input voltage range of the LT8638SEV#PBF?
The input voltage range is from 3.9V to 42V.
- What is the maximum continuous output current of the LT8638SEV#PBF?
The maximum continuous output current is 10A, with a peak current of up to 12A.
- What are the different operating modes supported by the LT8638SEV#PBF?
The device supports Burst Mode, Forced Continuous Mode (FCM), and spread spectrum mode, which can be configured using the SYNC/MODE pin.
- How does the LT8638SEV#PBF minimize EMI emissions?
The regulator features the second-generation Silent Switcher architecture and integrated bypass capacitors, which minimize EMI emissions. Additionally, it supports spread spectrum mode to further improve EMI performance.
- What is the package type and dimensions of the LT8638SEV#PBF?
The device is packaged in a 5mm x 4mm LQFN package with exposed pads for low thermal resistance.
- Can the LT8638SEV#PBF be used in automotive applications?
Yes, the LT8638SEV#PBF is available in automotive-grade versions, designated with a #W suffix, which are designed to support the quality and reliability requirements of automotive applications.
- How is the switching frequency set in the LT8638SEV#PBF?
The switching frequency can be set using a resistor tied between the RT pin and ground.
- What is the purpose of the SS pin in the LT8638SEV#PBF?
The SS pin allows user control of the output voltage ramp rate during start-up, enabling soft-start and tracking functionalities.
- Can the LT8638SEV#PBF be synchronized with an external clock?
Yes, the device can be synchronized with an external clock using the SYNC/MODE pin.
- What are the quiescent current characteristics of the LT8638SEV#PBF in different modes?
The quiescent current in shutdown is 6-9µA, and in sleep mode, it is 125-245µA.
