L99LD21 datasheet(17/73 Pages) STMICROELECTRONICS

Numer części	L99LD21

Szczegółowy opis	High power LED driver for automotive applications

PDF	73 Pages

Scroll/Zoom	100%

Producent	STMICROELECTRONICS [STMicroelectronics]

Strona internetowa	http://www.st.com

Logo

17 / 73 page

DS11130 Rev 5

17/73

L99LD21

Boost controller

The buck converters activation depends on device status (see Section 4.1: Operating

modes):

•

Active mode: in this case, bucks are immediately operative. Their status will depend on

DINMAP register configuration (see Section 4.2.1);

•

Limp Home:

–

we have to distinguish two different cases:

Boost Enabled with output voltage higher than 92.5% of final target value. In this

case, buck converters are immediately operative according to DIN_MAP register

configuration;

Boost Disabled or Enabled with output voltage lower than 92.5 % of final target

value. In this case, the buck converters are kept disabled for a specified time delay

(tDELAY) independently from DINMAP status. Once this time elapses, bucks are

operative according to DINMAP register configuration.

On the other hand, when boost and bucks are active and a VS undervoltage fault event

occurs, buck converters are immediately disabled while the boost is kept alive for tDELAY

before being switched off.

L99LD21 Arkusz danych(PDF) 17 Page - STMicroelectronics