Dld101 new prod uc t, Ordering information, Marking information – Diodes DLD101 User Manual
Page 7
DLD101
Document number: DS32007 Rev. 8 - 2
7 of 9
April 2010
© Diodes Incorporated
DLD101
NEW PROD
UC
T
Typical Application Circuit
8
7
6
5
1
2
3
4
C
E
B
G
D
S
R
C
R
S
Option 1
Option 2
Option 3
LED String
Option 3:
I
LED
≈
V
BE
R
S
Options 1 & 2:
I
LED
≈
1.1 V
BE
R
S
V
Supply
CC
Q2
Q1
V
DS
R2
R1
Option 2:
Capacitor is across R2 for
better noise performance.
The DLD101 has been designed primarily for solid state lighting
applications, to be used as a current sink circuit solution for LEDs. It
features a N-channel MOSFET capable of 1A drive current and a pre-
biased NPN transistor (which allows direct connection to the base, or
via a series base resistor).
Figure 12 shows a typical application circuit diagram for driving an
LED or string of LEDs. Note that the pre-biased transistor (Q2) has
the option of bypassing the series base resistor by connecting directly
to pin 7. The N-MOSFET (Q1) is configured as a V
BE
referenced
current sink and is biased on by R
C
. The current passed through the
LED string, MOSFET and source resistor, develops a voltage across
R
S
that provides a bias to the NPN transistor. Consideration of the
expected linear mode power dissipation must be factored into the
design, with respect to the DLD101's thermal resistance.
V
DS
= V
CC
– V
F LED String
– V
RS
P
Q1
= V
DS
* I
LED String
PWM dimming functionality can be effected by either driving the NPN
base via an additional resistor (thereby overriding the feedback from
R
S
) or by pulling the gate of the MOSFET down by direct connection.
The PWM control pulse stream can be provided by a micro-controller
or simple 555 based circuitry.
Fig. 12 Typical Application Circuit for
Linear Mode Current Sink LED Driver
Ordering Information
(Note 7)
Part Number
Case
Packaging
DLD101-7
DFN3030D-8
3000/Tape & Reel
Notes:
7. For packaging details, go to our website at
Marking Information
L101 = Product marking code
YYWW = Date code marking
YY = Last digit of year (ex: 10 for 2010)
WW = Week code (01 to 53)
DFN3030D-8
L101
YYW
W