ST8034HC datasheet(25/31 Pages) STMICROELECTRONICS

25 / 31 page

DocID024511 Rev 2

25/31

ST8034HN, ST8034HC

Functional description

Time delays



t11 = t10 + 3T / 64



t12 = t11 + T / 2



t13 = t11 + T



t14 = t11 + 3T / 2



tDEACT = t11 + 3T / 2 + VCC fall time.

T = 64 x 1/fOSC(INT).

Figure 11. Deactivation sequence

6.9

VCC generator

The LDO on the VCC output is capable of supplying up to 65 mA continuously at any

selected VCC value (5 V, 3 V or 1.8 V). This output is overcurrent protected by the current

limiter with a limit threshold value of 120 mA typ., with a glitch immunity allowing overcurrent

pulses up to 200 mA with duration up to several microseconds not causing a deactivation

(the average current value must stay below the specified current limit, see Table 6 on

page 11 and Table 10 on page 17).

A 100 nF capacitor (min.) with ESR < 350 m

 should be tied to GND near the VCC pin and

another low ESR 100 nF capacitor (min.) should be tied to GND also on the card side, near

the card reader contact C1.

ST8034HC Datenblatt(PDF) 25 Page - STMicroelectronics