DLD101

Document number: DS32007 Rev. 6 - 2

5 of 7

www.diodes.com

February 2010

© Diodes Incorporated

DLD101

Q2 Typical Performance Curves - continued

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

110

100

I , COLLECTOR CURRENT (mA)

C

Fig. 11 Typical Collector-Emitter Saturation Voltage

vs. Collector Current

I/I = 10

CB

T = -55°C

A

T = 25°C

A

T = 85°C

A

T = 125°C

A

T = 150°C

A

200

Typical Application Circuit

8

7

6

5

1

2

3

4

C

E

B

GD

S

R

C

R

S

Option 1

Option 2

Option 3

LED String

Option 3:

I

V

BE

R

S

Options 1 & 2:

I

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

LED string, MOSFET and source resistor, develops a voltage across

expected linear mode power dissipation must be factored into the

design, with respect to the DLD101's thermal resistance.

PWM dimming functionality can be effected by either driving the NPN

base via an additional resistor (thereby overriding the feedback from

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