april 2011 doc id 018762 rev 1 1/49 49 a5974ad up to 2 a step-down switching regulator for automotive applications features qualified following the aec-q100 requirements (see ppap for more details) 2 a dc output current operating input voltage from 4 v to 36 v 3.3 v / (2%) reference voltage output voltage adjustable from 1.235 v to 35 v low dropout op eration: 100% duty cycle 500 khz internally fixed frequency voltage feed-forward zero load current operation internal current limiting inhibit for zero current consumption synchronization protection against feedback disconnection thermal shutdown application dedicated to automotive applications description the a5974ad is a step-down monolithic power switching regulator with a minimum switch current limit of 2.5 a, it is therefore able to deliver up to 2 a dc current to the load depending on the application conditions. the output voltage can be set from 1.235 v to 35 v. the high current level is also achieved thanks to a hsop8 package with exposed frame, that allows to reduce the r thj-a down to approximately 40 c/w. the device uses an internal p-channel dmos transistor (with a typical r ds(on) of 250 m ) as switching element to minimize the size of the external components. an internal oscillator fixe s the switching frequency at 500 khz. having a minimum input voltage of only 4 v, it fits automoti ve applications requiring device operation even in cold crank conditions. pulse-by-pulse current limit with the internal frequency modulation offers an effective constant current short-circuit protection. hsop8 - exposed pad figure 1. application schematic ! - v s m a l l s i g n a l p o w e r p l a n e 6 4 / 6 6 / 5 4 6 # # 6 2 % & % 8
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