VX6854LC datasheet(25/114 Pages) STMICROELECTRONICS

25 / 114 page

DocID027110 Rev 2

25/114

VX6854LC

Functional description

3.4.3

Internal power-on reset (POR)

The VX6854LC internally performs a power-on reset (POR) when the 1V2 Vcore digital

supply rises through the trigger level, Vtrig_rising. Similarly, if the 1V2 Vcore digital power

supply falls through the trigger level, Vtrig_falling, then the power-on reset will also trigger.

Definitions:

Figure 10. POR timing

Rise threshold voltage (VTRIGR)

This is the supply voltage level that is recognised by the

POR as voltage “HIGH”. Only after the supply reaches

this level does the output of POR change to high level if

it is off, after a specified amount of delay.

Fall threshold voltage (VTRIGF)

This is the supply voltage level that is recognised by the

POR as voltage “LOW”. Only after the supply reaches

this level does the output of POR change to low (ground)

level if it is on.

Burst width (pw)

Burst is the negative pulse riding the supply signal. The

burst width is measured as the amount of duration for

which the supply signal dropped beyond the threshold

levels.

Delay duration (TPOR)

Delay duration is defined as the time duration for which

POR stays off before re-powering. Each reset of POR

will impart a specified delay duration before POR re-

powers.

Table 10. POR cell characteristics

Symbol

Constraint

Min

Typ.

Max

Units

VTRIGR

POR Rise Voltage detection

0.95

VTRIGF

POR Fall Voltage detection

0.4

Tburst (pw)

Burst Filter

µs

Tpor

Delay Duration

µs

VX6854LC датащи(PDF) 25 Page - STMicroelectronics

VX6854LC датащи(HTML) 25 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL