2 Application example using standby voltage monitoring

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Application example using standby voltage

monitoring

Figure 3.

Some applications may use external circuitry, for instance for advanced diagnosis in standby

mode. In figure 3 for example, an additional external resistive network is implemented, to

measure a potential short circuit or open load condition.

A short circuit or an open load condition can be detected by the ADC of a microcontroller, by

monitoring voltage levels of the resistive network.

entered. The voltage levels of the external circuitry could be influenced, eventually leading to a

temporary wrong diagnosis.

Hence it is mandatory to initialize the device if the application requires monitoring of voltage

not influenced. Later standby modes are also not influenced.

Once the device is initialized properly, the resistive output versus ground is always present

(figure 1) in standby mode.

M

Vcc

ADC

GH2

GL2

GH1

GL1

R

D1

R

D2

R

D3

S1

S2