LNBH23L

LNBH23L software description

Doc ID 15335 Rev 4

17/25

X = don't care

All values are typical unless otherwise specified

Valid with TTX pin floating

7.4

Diagnostic received data (I²C read mode)

LNBH23L can provide to the MCU master a copy of the diagnostic system register

information via I²C bus in read mode. The read mode is master activated by sending the

chip address with R/W bit set to 1. At the following master generated clocks bits, LNBH23L

issues a byte on the SDA data bus line (MSB transmitted first). At the ninth clock bit the

Master can:

●

Acknowledge the reception, starting in this way the transmission of another byte from

the LNBH23L

●

No acknowledge, stopping the read mode communication

Three bits of the register are read back as a copy of the corresponding write output voltage

register status (LLC, VSEL, EN), two bits convey diagnostic information about the over-

temperature (OTF), output over-load (OLF) and three bit are for internal usage (TEST1-2-3)

and must be disregarded by the MCU software. In normal operation the diagnostic bits are

set to zero, while, if a failure is occurring, the corresponding bit is set to one. At start-up all

the bits are reset to zero.

Table 6.

Truth table

PCL

TTX

TEN

LLC

VSEL

EN

TEST4 TEST5

Function

00

0

1

0

0

00

1

1

0

0

01

0

1

0

0

01

1

1

0

0

00

1

0

0

Internal 22 kHz generator disabled, EXTM

modulation enabled

10

1

0

0

Internal 22 kHz controlled by DSQIN pin (only if

TTX=1)

1

1

1

0

0

Internal 22 kHz tone output is always activated

01

0

0

OFF

11

0

0

ON

0

X

1

0

0

Pulsed (Dynamic) current limiting is selected

1

X

1

0

0

Static current limiting is selected

X

X

X

X

X

0

0

0

Power block disabled