Maxim’s New Self-Testing Voltage Monitor Features 1% Accuracy
Aimed at ADAS applications, the device tracks undervoltage and overvoltage while reducing both system complexity and BOM
Maxim’s MAX16137 is a single-window voltage monitor, which means that its main purpose in life is to assure that a given voltage point stays within a prescribed range. It also checks itself, with a built-in self-test (BIST), to assure the rest of the system that it is, in fact, reliably doing its job, all within a package sized at 2 x 2 mm.
The Max16137. Image courtesy of Maxim
A key advantage of the device, described as a supervisor, is that it can check its own functionality without the need for ancillary devices, thus reducing design complexity. This, along with the small package size, allows a design based on the MAX16137 to cut the overall solution size by 50%, as compared to competing solutions.
Designed for use in Advanced Automotive Applications
This supervisor IC will provide diagnostic and BIST at the chip level. This is required to allow engineers to provide the system-wide functional safety necessary for advanced automotive Applications (ADAS) and other autonomous driving applications.
As noted by Binay Bajaj, director of business management for the Core Products Group at Maxim Integrated, “Many automotive engineers are building autonomous driving systems where safety is paramount. They have requested higher accuracy supervisory circuits with programmable voltage thresholds and tolerance and built-in self-test, all to make their systems more robust.” He goes on to state that “We are helping engineers accelerate functional safety and the MAX16137 is the industry’s only supervisory IC with BIST to help engineers meet their goals.”
The MAX16137’s Operational Functionality
The device features factory-set voltage thresholds settable at 20 mV increments ranging from 0.5 to 5 volts. When the monitored voltage goes above the overvoltage limit or the undervoltage limits, the reset (RST) output pin asserts low, informing the Application Processor, as illustrated below.
A typical application circuit for the MAX16137. Image courtesy of Maxim's datasheet
After the reset timeout period, the reset dis-asserts when the measured voltage is within the prescribed range.
The units performs a BIST on-demand when it powers up and when the CLR/BIST pin is pulled low for more than 150μs. If the test fails, the BIST asserts low, informing the system through the Housekeeping Processor, as indicated above.
Fundamental Electrical Characteristics
The minimum and maximum operating voltage range (VDD) is 1.71 and 5.5 volts, respectively. Unless an alarm is being asserted, the MAX16137 typically draws 12 μA.
Aside for ADAS, the supervisor chip is also suited for use in:
- Storage equipment
- Multivoltage ASICs
- The MAX16137 operates over a temperature range of -40 to +125°C
- The unit is available in a 2 x 2 mm TDFN-8 side-wettable package for easier manufacturability
Regulatory and Safety
The device is AEC-Q100 qualified
System-level ASIL compliant
Getting to Market Faster
The MAX16137 Evaluation Kit offered by Maxim enables designers to evaluate and familiarize themselves with the supervisor IC.
The MAX16137 Evaluation Kit. Image courtesy of Maxim
The kit is delivered fully assembled with the MAX16137 installed, and it offers multiple test points to allow for a complete study.