MIC2298 Datasheet, PDF (2/13 Pages) Micrel Semiconductor – 3.5A Minimum, 1MHz Boost High Brightness White LED Driver

Micrel, Inc.
MIC2298
Ordering Information
Part Number
OVP
Frequency
Junction Temp. Range
Package
MIC2298-15YML
15V
1MHz
–40° to +125°C
12-Pin 3x3 MLF^®
Note: MLF^® is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Lead Finish
Pb-Free
Pin Configuration
BRT 1
SS/DIM 2
FB 3
AGND 4
PGND 5
PGND 6
12 COMP
11 EN
10 VIN
9 OVP
EP
8 SW
7 SW
12-Pin 3mm x 3mm MLF (ML)
(Top View)
Pin Description
Pin Number
1
2
3
4
5,6
7,8
9
10
11
12
Pad
Pin Name
BRT
SS/DIM
FB
AGND
PGND
SW
OVP
VIN
EN
COMP
EP
Pin Function
BRT (input): Apply a voltage greater than or equal to 1V to achieve full
brightness current as determined by the ballast resistor. A 10µA current source
sets the voltage on the resistor. Hence a 50K resistor would yield 0.5V which
causes a reduction in LED current to 50% of full brightness. Grounding the BRT
reduces the current further to 20% of full brightness. This pin may also be driven
by a PWM signal for the same effect.
Soft start/dimming (input) 40kΩ source. Connect a capacitor to GND for soft-
start. Clamp the pin to a known voltage to control the internal reference voltage
and hence the output current. This can also be done with a resistor to GND
Feedback (Input): Output voltage sense node. Connect the cathode of the LED
to this pin.
Analog Ground
Power Ground
Switch Node: Internal power BIPOLAR collector.
Over-Voltage Protection (OVP): Connect to the output voltage to clamp the
maximum output voltage. A resistor divider from this pin to ground could be
used to raise the OVP level beyond 15V (max)
Supply (Input): 2.5V to 10V for internal circuitry.
Enable (Input): Applying 1.5V or greater enables the regulator. Applying a
voltage of 0.4V or less disables the MIC2298.
Compensation pin (input): Add external R and C to GND to stabilize the
converter.
Ground (Return): Backside exposed pad.
October 2007
2
M9999-101707-B