An external resistive divider between a bandgap reference output, an ADC input, and ground determines which of the six channels are set to preset or adjustable voltage monitor inputs, as shown in the voltage threshold selection table below. The preset voltage thresholds are digitally configurable for 5%, 7.5%, 10% or 12.5% supply tolerances below the nominal operating voltage. The LTC2932 can also be configured to monitor up to four adjustable supplies, with the option for negative voltage monitoring by connecting a resistive divider between the negative supply and buffered reference instead of ground. All six preset or adjustable channels feature ±1.5% (max) threshold accuracy over the entire temperature range.
With guaranteed specifications across the -40°C to +125°C temperature range, the LTC2932 can be used in automotive and military applications. The LTC2932’s reset timeout period can be adjusted using an external capacitor and the reset output is guaranteed to be in the correct state for VCC as low as 1V. The LTC2932 also includes a reset disable pin for margining applications.
The LTC2932 is releasing alongside two new six-channel configurable supervisors. The LTC2931 offers similar functionality and performance, while including a watchdog input, adjustable watchdog timer, and a fixed 5% monitor threshold. The LTC2932 and LTC2931 are both offered in 20-pin TSSOP packages. The LTC2930 includes a push-button manual reset input and uses only a single reset output for voltage monitoring, and is available in a tiny 3mm x 3mm DFN-12 package. All three six-channel supervisors draw only 52uA of supply current.