TD350ID datasheet(9/17 Pages) STMICROELECTRONICS

9 / 17 page

TD350

Functional description

Doc ID 9525 Rev 6

9/17

5.6

Minimum ON time

In order to ensure the proper operation of the 2-level turn-off function, the input ON time

(Twin) must be greater than the Twinmin value:

Twinmin=Ta+2*Rdel*Coff

Rdel is the internal discharge resistor and Coff is the external timing capacitor.

Input signals smaller than Ta are ignored. Input signals larger than Twinmin are transmitted to

the output stage after the Ta delay with minimum width distortion (ΔTw=Twout-Twin).

For an input signal width Twin between Ta and Twinmin, the output width Twout is reduced

below Twin (pulse distortion) and the IGBT could be partially turned on. These input signals

should be avoided during normal operation.

5.7

Output

The output stage is able to sink 2.3 A and source 1.5 A typical at 25 °C (1.2 A/0.75 A

minimum over the full temperature range). Separated sink and source outputs allow

independent gate charge and discharge control without an extra external diode.

5.8

Fault status output

Fault output is used to signal a fault event (desaturation, UVLO) to a controller. The fault pin

is designed to drive an optocoupler.

5.9

Undervoltage protection

Undervoltage detection protects the application in the event of a low VH supply voltage

(during start-up or a fault situation). During undervoltage, the OUTH pin is open and the

OUTL pin is driven low (active pull-down for VH>2 V, passive pull-down for VH<2 V). Fault

output signals the undervoltage state and is reset only when undervoltage state disappears.

Figure 3.

Undervoltage protection

OUT

UVH

UVL

Vccmin

FAULT

TD350ID Datasheet(PDF) 9 Page - STMicroelectronics