LED2000DR STMicroelectronics, LED2000DR Datasheet - Page 15

• Manufacturer Part Number: LED2000DR
• Description: Current & Power Monitors & Regulators 3A monolithic Conv 850kHz Synch
• Manufacturer: STMicroelectronics

Specifications of LED2000DR

• Rohs: yes
• Product: Current Regulators
• Supply Voltage - Max: 14.7 V
• Supply Voltage - Min: 14.1 V
• Input Voltage Range: 14.1 V to 14.7 V

LED2000
6.4
The embedded compensation network is R
considered as negligible. The error amplifier output resistance is 240 M
singularities are:
Equation 12
LED small signal model
Once the system reaches the working condition, the LEDs composing the row are biased
and their equivalent circuit can be considered as a resistor for frequencies << 1 MHz.
The LED manufacturer typically provides the equivalent dynamic resistance of the LED
biased at different DC currents. This parameter is required to study the behavior of the
system in the small signal analysis.
For instance, the equivalent dynamic resistance of the Luxeon III Star from Lumiled
measured with different biasing current level is reported below:
Equation 13
If the LED datasheet does not report the equivalent resistor value, it can be simply derived
as the tangent to the diode I-V characteristic in the present working point (see
f
Z
=
r
LED
11 6 kHz
1.3
0.9
f
P LF
I
I
LED
LED
=
3 4 Hz
=
=
350mA
700mA
Doc ID 023432 Rev 3
C
=70 K, C
C
=195 pF while C
P
Application notes
and C
so the relevant
Figure
O
can be
7).
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