MAX25239 MAX25240 dcdc app

“MAX25239 and MAX25240 small-footprint 2V to 36V converters are the industry’s only 6A automotive buck-boost with integrated H-bridge switches,” according to distributor Farnell, which is stocking the parts. “They provide a fixed-output regulation voltage and an externally adjustable output voltage from 3V to 20V.”

MAX25239 MAX25240 dcdc blockThe ‘and’ in this last sentence should be ‘or’, as there is a single output. Whether it is set to the factory-set fixed voltage (there are multiple version of the device for different fixed voltages) or it is adjustable depends on what is happening to the feedback input: connect it directly to Vcc to get the factory-set fixed voltage, or to the output via a resistive divider to adjust the output between 3V and 6.5V, or between 6V and 20V, depending on another factory setting*

Factory options are: input current limit (8.2, 10 or 12A), fixed output voltage (5, 10.5 or 11.5V), adjustment range (above or below 6.5V*) and switching frequency (200kHz, 400kHz or 2.1MHz), and ADI can produce custom versions.

Protections include under-voltage lock-out, over-voltage, cycle-by-cycle current limit and thermal shutdown, plus there is a power-ok output and the ability to add spectrum spreading, and to force PWM operation instead of the low output power saving mode. Many inputs are tolerant to 42V transients.

Packaging is 4.25 x 4.25 x 0.75mm 22pin FC2QFN.

“Applications include ADAS ECU, body electronics, infotainment systems, point-of-load power supplies and start-stop systems,” said Farnell, which is stocking an evaluation kit built around the 11.5V, 400kHz MAX25240AFFF/VY+, which can “also be used to evaluate other MAX25240 variants”.

Here is the web page link provided by Farnell, and the evaluation kit is here,

*but take the 6.5V part with a pinch of salt, as it comes from Electronics Weekly’s reading of read pages 13 and 23 of the data sheet (rev8) so check it four yourself if it is important to you. Farnell has been asked for this information, and for the exact distinction between the MAX25239 and MAX25240

If you know already, please comment below.

BTW, also take a look at the data sheet just for interest, as there is a lot going on in this device.