Analog Devices Inc. LT8686S Step-Down Regulators
Analog Devices LT8686S Step-Down Regulators are highly flexible, four-channel, current-mode, monolithic regulators for automotive and industrial power systems. The device combines two high-voltage synchronous buck regulators with two low-voltage synchronous buck regulators to support multiple regulated rails while minimizing board space. The LT8686S supports gangable operation, allowing two high-voltage or low-voltage channels to connect in parallel using a single inductor to achieve higher output current. The ADI LT8686S Step-Down Regulators also offer individual channel enable, track/soft-start, and power-good pins for flexible sequencing and system-level power control.
The regulators are excellent for automotive systems, industrial controls, and industrial power supplies requiring efficient, compact, and EMI-conscious DC/DC conversion. The LT8686S uses the Silent Switcher® 2 architecture with optional spread-spectrum modulation and integrates thermal shutdown and individual-channel cycle-by-cycle current limit protection for robust operation.
Features
- Silent Switcher 2 architecture for ultralow EMI emissions
- Optional spread spectrum modulation for EMI mitigation
- Four-channel current-mode monolithic regulator architecture
- Gangable high-voltage and low-voltage channel pairs using a single inductor
- Flexible power supply sequencing and control through individual enable, track/soft-start, and power-good pins
- Adjustable and synchronizable switching operation for flexible system design
- High efficiency at high switching frequencies
- Thermal shutdown and individual channel cycle-by-cycle current limit for short-circuit protection
- AEC-Q100 qualified for automotive applications
Applications
- Automotive power systems
- Industrial controls
- Industrial power supplies
- Compact multi-rail DC/DC conversion designs
Specifications
- Two high-voltage synchronous buck regulators
- Input voltage range of 3V to 42V
- Output current of up to 2A per channel
- Parallel operation of up to 4A using a single inductor
- Two low-voltage synchronous buck regulators
- Input voltage range of 3V to 8V
- Output current of up to 2A per channel
- Parallel operation of up to 4A using a single inductor
- Quiescent current of 12μA with all channels active and no load
- Switching frequency range of 350kHz to 3MHz
- Operating junction temperature range of -40°C to +150°C
- Package
- 32-pin LQFN package
- 5mm x 5mm package size
Demonstration Circuit
Analog Devices Inc. DC3126A Demonstration Circuit
Quad power supply based on the LT8686S 42V current mode monolithic synch step-down regulator.
Typical Application
Block Diagram
