UM0575

Board performances

11/20

If a failure occurs on the control side, leading to a short-circuit of both the power switch and

the PTC, then the start winding could be damaged as its current would not be limited. The

solution is then to use a thin copper track (Figure 15) between the start winding terminal and

the e-STARTER control circuit. For example, a 130 µm track conducts the 1mA peak current

in normal operation but blows if the whole start winding current, at least equal to 5 A RMS,

circulates through it. The ACST6 then remains on the entire time the thermostat switch is

closed. The behavior is the same as a standard PTC, without the power saving function of

the e-STARTER.