Voltage monitor and reset chip has BIST for ADAS


MAX16237 block BIST reset

Called MAX16137, it has two forms of BIST (built-in self-test): one that checks the chip at power-up and a second that checks on-demand.

Just like any reset chip, it holds its reset output low as power-up progresses, then releases it high after a (factory settable) delay once the rail is established. It also detects under-voltage and over-voltage conditions. In the case of an over-voltage, the chip pulls both the reset pin low and an over-voltage indicator pin that can be used to shut down the potentially-offending regulator (see typical application circuit below).

At power up, around the time the power rails are established and reset is being released, the internal on-demand BIST generates fictitious under-voltage and over-voltage faults and, if the internal circuit does not respond properly, pulls reset low as well as the fault-indicating ‘BIST’ output pin.

A caveat here: do check the data sheet yourself – there is a bit more too it that the simplified version here. Back to the IC:

At any time during normal operation, BIST can be initiated by pulling the CLR/BIST input pin low. One of two things happens then, controlled by the NR input pin (see diagrams).

MAX16237

If NR is low, a reset is initiated while the test is in operation, and the result indicated through there BIST output – much like a power-up.

If NR is high, the test happens without a reset being asserted, with the result again indicated by the BIST pin.

Through factory settings, the IC’s nominal voltage can be anywhere from 0.5V to 5V in ~20mV increment.

Over-voltage and under-voltage thresholds are symmetrical about this, factory-trimmed from ±4% to ±11% in ±1% increments. Reset time-out is set at the factory between 200 to 1,500ms.

“Functional safety standards drive design direction in the automotive space,” according to the company. “Voltage monitors play a key role in reporting the health of power supplies. MAX16137 delivers both diagnostic and BIST at the chip level to help designers achieve system-wide functional safety for ADAS and other autonomous driving applications. The supervisory IC can be designed into a variety of automotive systems such as infotainment, body electronics, power, electric vehicle power powertrain and IoT systems.”

It comes in a 2 x 2mm, 8pin TDFN side-wettable package with exposed pad, and operates over -40°C to +125°C.

The MAX16137 product page is here, and the data sheet here.





Source link

We will be happy to hear your thoughts

Leave a reply

Out Put Source
Logo
Enable registration in settings - general
Compare items
  • Total (0)
Compare
0
Shopping cart