3.5-A, 36-V synchronous, 2.1-MHz, automotive step-down DC-DC converter

The LM53625-Q1/LM53635-Q1 synchronous

buck regulator is optimized for automotive applications, providing an output voltage

of 5 V, 3.3 V, or an adjustable output. Advanced high-speed circuitry allows the

LM53625-Q1/LM53635-Q1 to regulate from an input of 18 V to an output of 3.3 V at a

fixed frequency of 2.1 MHz. Innovative architecture allows this device to regulate a

3.3-V output from an input voltage of only 3.55 V. All aspects of the

LM53625-Q1/LM53635-Q1 are optimized for automotive and performance-driven industrial

customers. An input voltage range up to 36 V, with transient tolerance up to 42 V,

eases input surge protection design. The automotive-qualified Hotrod QFN package

with wettable flanks reduces parasitic inductance and resistance while increasing

efficiency, minimizing switch node ringing, and dramatically lowering

electromagnetic interference (EMI). An open-drain reset output, with built-in

filtering and delay, provides a true indication of system status. This feature

negates the requirement for an additional supervisory component, saving cost and

board space. Seamless transition between PWM and PFM modes and low quiescent current

(only 15 µA for the 3.3 V option) ensure high efficiency and superior transient

responses at all loads.