VN7040AS datasheet(36/55 Pages) STMICROELECTRONICS

36 / 55 page

Application information

VN7040AJ, VN7040AS

36/55

DocID027400 Rev 3

Figure 41: GND voltage shift

VCC monitor

Battery monitoring channel provides VSENSE = VCC / 8.

Case temperature monitor

Case temperature monitor is capable of providing information about the actual device

temperature. Since a diode is used for temperature sensing, the following equation

describes the link between temperature and output VSENSE level:

VSENSE_TC (T) = VSENSE_TC (T0) + dVSENSE_TC / dT * (T - T0)

where dVSENSE_TC / dT ~ typically -5.5 mV/K (for temperature range (-40 °C to 150 °C)).

4.4.3

Short to VCC and OFF-state open-load detection

Short to VCC

A short circuit between VCC and output is indicated by the relevant current sense pin set to

VSENSEH during the device off-state. Small or no current is delivered by the current sense

during the on-state depending on the nature of the short circuit.

OFF-state open-load with external circuitry

Detection of an open-load in off mode requires an external pull-up resistor RPU connecting

the output to a positive supply voltage VPU.

It is preferable that VPU is switched off during the module standby mode in order to avoid

the overall standby current consumption to increase in normal conditions, i.e. when load is

connected.

RPU must be selected in order to ensure VOUT > VOLmax in accordance with the following

equation:

Equation

PU <

PU - 4

L(off2)min @4V

VN7040AS 数据表(PDF) 36 Page - STMicroelectronics