L9779WD datasheet(92/170 Pages) STMICROELECTRONICS

92 / 170 page

Functional description

L9779WD

92/170

DocID027452 Rev 5

6.14

ISO serial line (K-LINE)

Figure 56. ISO serial line (K-LINE) circuit

6.14.1

ISO serial line (K-LINE) functionality description

The ISO serial line is an interface containing one bidirectional line for communication

between the µP and an external diagnosis tester or anti-theft device. In case of ground loss

the outputs K_LINE get in high impedance state and can withstand a negative voltage up to

-18 V. Short circuit to Vb protection is provided: if the K_LINE pin is shorted to battery the

output is switched off after a delay of tfilter_K_LINE and it is necessary an input change to

turn on it again.

The negative transition at K_LINE pin can be driven with slew-rate limitation for optimizing

the EMI behavior. This slew-rate limitation must be enabled via the ISO_SRC bit.

The K_TX signal is ignored (K_LINE pin to high level) until the RST pin is asserted.

KLINE can work up to 250 kHz input frequency in typical application condition.

Table 41. ISO serial line (K-LINE) functionality electrical characteristics

Symbol

Parameter

Test condition

Min

Typ

Max

Unit

K_TX

VKTXL

K_TX input low voltage -

-0.3

1.1

VKTXH

K_TX input high

voltage

-2.3

VDD

+0.3

RTX_KPU

TX_KLINE pull-up

resistor

250

kΩ

ITXsink

Transmitter input sink

current

K_LINE = 0, K_TX = High

µA

L9779WD bảng dữ liệu(PDF) 92 Page - STMicroelectronics

L9779WD bảng dữ liệu(HTML) 92 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

bảng dữ liệu tải về

Link URL