STCC08 datasheet(5/13 Pages) STMICROELECTRONICS

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STCC08

Functional description

5/13

Functional description

STCC08 functional description

The STCC08 is a power circuit designed to drive up to 10 mA IGT AC switches and to detect

AC switch failure modes through MCU diagnostic.

It embeds a logic switch driver, an AC switch diode mode detection, a short circuit detection

and an AC switch open detection.

STCC08 can be powered by a 3.3 V or 5 V power supply voltage.

Switch driver

This driver is a logic level buffer (CMOS compatible) interfacing directly with the AC switch

and the microcontroller.

The AC switch must be driven in negative polarity: AC switch COM = A1 = VCC

The drive Boolean rule is:

Vin > Von: switch = ON

Vin < Von: switch = OFF

The AC switch can be driven in continuous, pulsed or angle phase modes.

In insulated applications, the input can be driven through an opto-coupler powered with a

non-insulated auxiliary power supply.

RIG pin allows the AC switch gate current to be set. A resistor must be connected between

this pin and the ground GND. This resistor is defined according to the miminmum ambient

temperature and the AC switch IGT (see Figure 3). This optimizes the consumption of the

application.

Figure 3.

Rig = f(Tamb_min) for 5/10 mA AC switches

100

110

120

130

-20

-15

-10

-5

RIG_Max(

Ω)

AC switch 10 mA @ 25 °C

AC switch 5 mA @ 25 °C

Tamb_min (°C)

STCC08 Scheda tecnica(PDF) 5 Page - STMicroelectronics