LED2000DR STMicroelectronics, LED2000DR Datasheet - Page 9

• 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
5
5.1
Functional description
The LED2000 is based on a “peak current mode” architecture with fixed frequency control.
As a consequence, the intersection between the error amplifier output and the sensed
inductor current generates the control signal to drive the power switch.
The main internal blocks shown in the block diagram in
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Figure 3.
Power supply and voltage reference
The internal regulator circuit consists of a startup circuit, an internal voltage pre-regulator,
the BandGap voltage reference and the bias block that provides current to all the blocks.
The starter supplies the startup current to the entire device when the input voltage goes high
High-side and low-side embedded power element for synchronous rectification
A fully integrated sawtooth oscillator with a typical frequency of 850 kHz
A transconductance error amplifier
An high-side current sense amplifier to track the inductor current
A pulse width modulator (PWM) comparator and the circuitry necessary to drive the
internal power element
The soft-start circuitry to decrease the inrush current at power-up
The current limitation circuit based on the pulse-by-pulse current protection with
frequency divider
The dimming circuitry for output current PWM
The thermal protection function circuitry.
SOFT-START
0.1V
LED2000 block diagram
OSC
E/A
Vsum
Vc
PWM
OCP
REF
COMP
Doc ID 023432 Rev 3
OCP
FB
OTP
REGULATOR
CONTROL
DIMMING
MOSFET
LOGIC
UVLO
DIM
I V
N
A
Vdrv _p
Vdrv _n
I2 V
Figure 3
DRIVER
DRIVER
I _ SENSE
DMD
are:
GNDA
Functional description
R
SENSE
I V
GNDP
N
AM12894v1
S
W
SW
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