Triple 60mA Linear LED Controller
Preliminary Information - Jan 21, 2015
E522.84/85/86/87
The interface IR is used to configure the current for all LEDx channels. The current flow in IR is multiplied to LEDx by a factor of
typical 385:1. Digital dimming can be used at ENA by applying VENA > 3V or VENA < 1V.
Various factors influence the reference voltage driven to IR as an output. Details are illustrated in „Figure 1. IR Reference Gen-
eration“.
In nominal case (typical junction temperature, VENA > 3V) the internal reference is used. The lowest reference applied to the
amplifier shown in „Figure 1. IR Reference Generation“ is used to regulate VIR.
VREF
VREF,NOM
dVJ,DERATE
Operating Range for
external VREF = VENA /2
Limited
by abs.
max. Ratings
VENA,ON /2
E522.8x disabled by ENA
TJ
-40°C
150°C
TJ,DERATE
TJ,OT
Figure 2. Principle of Internal Temperature Derating
The internal reference derating function implemented is rather tolerant to allow external configuration of derating by the
user. It typically starts to derate the internal reference at TJ = 138°C, falling with typ. -26.7mV/K beyond this temperature. The
range of operating E522.8x with external reference or external derating is shown in „Figure 2. Principle of Internal Temperature
Derating“.
To realize an external derating function and shutdown, it is possible to use e.g. a temperature dependent resistor divider at
ENA. In the range of typically 3V down to VENA,OFF the voltage VENA/2 is used to drive VIR. Falling below VENA,OFF disables E522.8x,
restarting with VENA,ON
.
This document contains information on a pre-production product. Elmos Semiconductor AG reserves the right to change specifications and information herein without notice.
Elmos Semiconductor AG
Data Sheet
QM-No.: 25DS0137E.00
10/20
ELMOS [ ELMOS SEMICONDUCTOR AG ]
