Linear LT3641 4V to 42V Input Buck Regulator Circuitry

TP-IP4220CZ6 5V 0.35PF breakdown voltage 6V SOT

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

Shunuo varistor / ESD varistor / product complete / Sunlord first-class agent

Industrial Router Crystal 3.2*2.5mm 3225 26M (26.000MHZ) 12PF 10PPM 20PPM 30PPM

Photocoupler

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Integrated microprocessor monitoring supports high reliability applications such as automotive electronic control units. The LT3641 includes a power-on reset timer, each channel and a common watchdog timer. The reset and watchdog timeout periods are independently adjustable using an external capacitor. Strict accuracy specifications and immunity to interference ensure reliable reset operation of the system without false triggering. The LT3641 implements a window watchdog timer that monitors WDI drop packets that are too close or far apart.

4V to 42V Input Buck Regulator Circuit

Linear Technology introduces the LT3641, a dual-channel, current-mode step-down switching regulator power-on reset and watchdog timer. Its 4V to 42V input voltage range of 55V transient capability makes it commonly used in automotive applications, even with the need for input transients up to 55V with high constant output regulation for load dump and cold cranking. The LT3641's non-synchronous channel with high input voltage (4VIN to 42VIN, 55VIN transient capability) provides 1.3A of output current combined with a low input voltage (2.5VIN to 5.5VIN) sync channel, providing up to a unique The dual channel design has a continuous output current of 1.1A. While some allow independent inputs for each channel, most applications will use a high voltage channel to output a lower voltage channel, providing dual outputs while optimizing efficiency and switching frequency. For example, using a nominal 12V input and a 2MHz switching frequency, the LT3641 is capable of delivering 3.3V at 600mA with an output efficiency of 85% and 90% secondary conversion efficiency through its lower voltage, through the high voltage channel and 1.8V output at 800 mA channel.

Integrated microprocessor monitoring supports high reliability applications such as automotive electronic control units. The LT3641 includes a power-on reset timer, each channel and a common watchdog timer. The reset and watchdog timeout periods are independently adjustable using an external capacitor. Strict accuracy specifications and immunity to interference ensure reliable reset operation of the system without false triggering. The LT3641 implements a window watchdog timer that monitors WDI drop packets that are too close or far apart.

The LT3641's switching frequency is user-programmable from 350kHz to 2.5MHz, allowing designers to optimize efficiency while avoiding critical noise-sensitive frequency bands. Also, its low minimum time allows it to provide high switching frequencies and even high step-down ratios. Even with a high input of up to 35V, for example, it can provide a 3.3V and 1.1V output with a 2MHz switching frequency, enabling it to avoid critical frequency bands such as AM radios while minimizing the size of external components. The LT3641 provides an output voltage as low as 1.26V with its high voltage channel and a low, 0.6V low voltage channel, enabling it to be powered by the latest generation of microprocessors. Its low ripple burst mode operation reduces the quiescent current by only 290μA below the output ripple of 15mVPK - PK, making it ideal for applications such as automotive or telecommunications systems, always maintaining turn-on operation and optimal battery life. The LT3641's 4mm x 5mm QFN package -28 (or TSSOP-28) package and high switching frequency keeps the external inductors and capacitors small, providing a very compact footprint with high thermal efficiency.