3.6 System Lock

The MTCH9010 liquid detector provides a System Lock mechanism that saves the parameters configured through the Enhanced Configuration mode in the Nonvolatile Memory (NVM) and restores the settings at every start-up. Enable this feature at the next start-up after the Enhanced Configuration and calibration process.

The parameters configured using the Enhanced Configuration mode are stored in the NVM at two memory locations for redundancy purposes. The application will load the parameters from the first memory location and use the second memory location only if the loading fails.

Important: If the saved configuration is compromised in both memory locations (due to incomplete configuration or data corruption), the device will enter an error state, as indicated by the OUT and HB pins. Refer to the Error State chapter.

The SYS_LK digital input pin controls the usage of the System Lock mode. The following table shows the correspondence between the SYS_LK pin voltage and System Lock settings:

Table 3-7. System Lock Settings
Voltage on SYS_LK Pin	System Lock
0V	Enabled
V_DD	Disabled

Note: If the parameters validation process detects data corruption in the saved parameters, the device enters the Error state. Refer to the Error State chapter.

Figure 3-1. System Lock Flow Diagram