Analog Devices Inc. LTC3311 & LTC3311S Step-Down Silent Switchers

Analog Devices Inc. LTC3311 and LTC3311S Synchronous Step-Down Silent Switchers provide up to 12.5A of output current from a 2.25V to 5.5V input supply. The LTC3311 has a Silent Switcher 1 architecture and the LTC3311S has a Silent Switcher 2 architecture. Both variants integrate internal hot loop bypass capacitors to achieve both low EMI and high efficiency at switching frequencies as high as 5MHz. Multi-phasing parallel converters are readily implemented for systems with higher power requirements.

The Analog Devices Inc. LTC3311 and LTC3311S use a constant frequency, peak current mode control architecture for fast transient response. A 500mV reference allows for low voltage outputs. 100% duty cycle operation delivers low dropout.

The LTC3311 and LTC3311S also include a Power Good signal when the output is in regulation, precision enable threshold, output overvoltage protection, thermal shutdown, a temperature monitor, clock synchronization, mode selection, and output short circuit protection.

The pin-compatible LTC3311 and LTC3311S Step-Down Silent Switchers are available in a compact 3mm x 3mm LQFN-18 package. Both variants are AEC-Q100 qualified for automotive applications.

Applications

Automotive/industrial/communications
Servers, telecom power supplies

Distributed DC power systems (POL)
FPGA, ASIC, µP core supplies

Features

Pin Compatible with LTC3310 and LTC3310S
Silent Switcher
- LTC3311: Silent Switcher 1 Architecture
- LTC3311S: Silent Switcher 2 Architecture
High-efficiency 4.5mΩ NMOS and 16mΩ PMOS
Wide bandwidth, fast transient response
Safely tolerates inductor saturation in overload
V_IN range: 2.25V to 5.5V
V_OUT range: 0.5V to V_IN
V_OUT accuracy: ±1% with Remote Sense
Peak current-mode control