AN4069 datasheet(8/16 Pages) STMICROELECTRONICS

Part #	AN4069

Description	This demonstration board is based on the STEF05 and STEF12 electronic fuses

PDF	16 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

Logo

8 / 16 page

Output dV/dt circuit

AN4069

8/16

Doc ID 022926 Rev 1

Output dV/dt circuit

The demo board comes with no CdV/dt mounted. In this condition, after an initial delay time

of typically 500 µs for the STEF05 and 350 µs for the STEF12, the output voltage is supplied

with a slope defined by the internal dv/dt circuitry.

The total time from the enable signal going high and the output voltage reaching the nominal

value is typically 1 ms. The output voltage slew rate can be customized by mounting the

dV/dt capacitors (C1, C2). The suggested values range is 10 pF to 1 nF.

Given the desired time interval

Δt during which the output voltage goes from zero to its

maximum value, the capacitance to be added on the Cdv/dt pin can be calculated using the

following theoretical formulas:

●

STEF05 dV/dt setting

Cdvdt = 50 × 10-9Δt - 30 × 10-12

●

STEF12 dV/dt setting

Cdvdt = 24 × 10-9Δt - 30 × 10-12

Figure 6.

STEF05 delay time and VOUT ramp-up time

AN4069 Datasheet(PDF) 8 Page - STMicroelectronics