Microchip MIC3202YME Handleiding

Microchip Niet gecategoriseerd MIC3202YME

Lees hieronder de 📖 handleiding in het Nederlandse voor Microchip MIC3202YME (7 pagina's) in de categorie Niet gecategoriseerd. Deze handleiding was nuttig voor 37 personen en werd door 2 gebruikers gemiddeld met 4.5 sterren beoordeeld

Download PDF
Pagina 1/7
MIC3202/MIC3202-1
Evaluation Board
High-Brightness LED Driver with Integrated
MOSFET and High-Side Current Sense
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
October 2010 M9999-102810
General Description
The MIC3202/MIC3202-1 is a hysteretic step-down,
constant-current, High-Brightness LED (HB LED) driver.
It provides an ideal solution for interior/exterior lighting,
architectural and ambient lighting, LED bulbs, and other
general illumination applications.
This board enables the evaluation of the
MIC3202/MIC3202-1 for 1A LED current. The board is
optimized for ease of testing, with all the components on
a single side. The device operates from a 6V to 37V
input voltage range, and includes an integrated 1.0A
MOSFET. When the input voltage approaches and
crosses UVLO threshold, the internal 5V VCC is
regulated and the integrated MOSFET is turned on if EN
pin and DIM pin are high. The inductor current builds up
linearly. When the CS pin voltage hits the V CS(MAX) with
respect to VIN, the internal MOSFET is turned off and the
Schottky diode takes over and returns the current to V IN.
Then the current through inductor and LEDs starts
decreasing. When CS pin hits VCS(MIN), the internal
MOSFET is turned on and the cycle repeats.
Since the control scheme does not need loop
compensation, it makes for a very simple design and
avoids problems of instability.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Requirements
This board needs a single-bench power source
adjustable over the input voltage of 6V < V IN < 37V that
can provide at least 1A of current. The loads can either
be active (electronic load in CV mode) or passive
(LEDs) with the ability to dissipate the maximum load
power while keeping accessible surfaces ideally <70°C.
Precautions
There is no reverse input protection on this board. When
connecting the input sources, ensure that the correct
polarity is observed.
In the line transient condition, such as hot plug-in, an
electrolytic capacitor may be required at the VIN and
GND terminals in order to prevent IC damage from a
surge voltage.
Getting Started
1. Connect VIN supply to the input VIN and GND
terminals. With the output of this supply disabled,
set the supply voltage to the desired input test
voltage (6V < VIN < 37V). This supply voltage should
be monitored at the test boards input terminals to
allow voltage drops in the test cables (and ammeter
if used) to be accounted for. An ammeter can be
added inline with the +VIN input terminal to
accurately measure input current.
2. Connect the LEDs to the output terminals
between LED+ and LED−
−
−
−−. This LED voltage drop
depends on manufacturer tolerance and number of
LEDs. The LED current can be measured using an
ammeter or current probe. A 4.7µF ceramic
capacitor helps to reduce the current ripple through
the LED. The LED current is set to 1A by a 200mΩ
current-sense resistor (RCS).
3. Enable the input supply. By default, the IC is
enabled when the input voltage crosses the VIN
threshold (4V) and the internal VCC regulator and
internal MOSFET are turned on with the EN and
DIM pins are high. To use the EN and DIM functions
of the MIC3202/MIC3202-1, a test point is provided
for each of them.
Ordering Information
Part Number Description
MIC3202YME EV MIC3202YME Evaluation Board
Micrel, Inc. MIC3202/MIC3202-1 Evaluation Board
October 2010 2 M9999-102810
Other Features
EN Input
The EN pin provides a logic level control of the output
and the voltage has to be 2.0V or higher to enable the
current regulator. The output stage is gated by the DIM
pin. When the EN pin is pulled low, the regulator goes to
off-state and the supply current of the device is reduced
to below 1µA. Do not drive the EN pin above the supply
voltage.
DIM Input
The DIM pin provides a logic level control for brightness
of the LED. A PWM input can be used to control the
brightness of LED. DIM high enables the output and its
voltage has to be 2.0V or higher. DIM low disables the
output, regardless of EN high-state.
Current-Sense Input
The CS pin provides the high-side current sense to set
the LED current with an external sense resistor.
A sense resistor RCS is placed between VIN and LED+
terminals.
The current through LED is sensed by the sense resistor
(RCS). The sensed voltage is fed back to the MIC3202 to
regulate the LED current
RCS is given by:
)
I
V+V
(x
2
1
=R
LED
)MIN(CS)MAX(CS
CS Error!
Bookmark not defined.
ILED is LED current required to set.
RCS (Ω) ILED (A) I2R (W) Size (SMD)
1.33 0.15 0.03 0603
0.56 0.35 0.07 0805
0.4 0.5 0.1 0805
0.28 0.7 0.137 0805
0.2 1.0 0.2 1206
For VCS(MAX) and VCS(MIN) refers to the Electrical
Characteristics table.
Frequency of Operation
To calculate the frequency spread across input supply:
)V+V(×IΔ×L
)VR×IV(×)V+R×I+V(
=F
INDL
LEDCSLEDINLEDCSLEDD
SW
--
CS
)MIN(CS)MAX(CS
LR
VV
=IΔ
-
where:
VD is Schottky diode forward drop
VLED is total LEDs voltage drop
VIN is input voltage
ILED is average LED current
According to the above equation, choose the inductor to
make the operating frequency no higher than 1MHz.
Refer to the datasheet Application Information for more
information on components selection guidelines.
Frequency Dithering
The MIC3202 is designed to modulate the V CS(MAX) with
amplitude ±6mV by a pseudo random generator to
generate the ±12% of the switching frequency dithering.
This spreads the frequency spectrum over a wider range
and reduce the EMI noise peaks.
The MIC3202-1 is non-dithering version of the MIC3202.
Micrel, Inc. MIC3202/MIC3202-1 Evaluation Board
October 2010 3 M9999-102810
Evaluation Board Performance

Product specificaties

Merk: Microchip
Categorie: Niet gecategoriseerd
Model: MIC3202YME

Heb je hulp nodig?

Als je hulp nodig hebt met Microchip MIC3202YME stel dan hieronder een vraag en andere gebruikers zullen je antwoorden


Handleiding Niet gecategoriseerd Microchip

Microchip

Microchip EVB-USB2504 Handleiding

17 November 2024
Microchip

Microchip AT97SC3204 Handleiding

17 November 2024
Microchip

Microchip ATECC608B Handleiding

16 Juli 2024
Microchip

Microchip HV860 Handleiding

16 Juli 2024
Microchip

Microchip EVB-LAN9255 Handleiding

16 Juli 2024
Microchip

Microchip LX4580 Handleiding

16 Juli 2024
Microchip

Microchip LX7720 Handleiding

16 Juli 2024
Microchip

Microchip AT32UC3C0128C Handleiding

10 April 2024
Microchip

Microchip AT32UC3C1512C Handleiding

10 April 2024
Microchip

Microchip AT32UC3A3256 Handleiding

10 April 2024

Handleiding Niet gecategoriseerd

Nieuwste handleidingen voor Niet gecategoriseerd

Livarno Lux

Livarno Lux IAN 071407 Handleiding

29 November 2024
Livarno Lux

Livarno Lux IAN 317128 Handleiding

29 November 2024
Livarno Lux

Livarno Lux IAN 049213 Handleiding

29 November 2024
Livarno Lux

Livarno Lux ST-1002 Handleiding

29 November 2024
Livarno Lux

Livarno Lux HG02489 Handleiding

29 November 2024
Livarno Lux

Livarno Lux HG02189 Handleiding

29 November 2024
Livarno Lux

Livarno Lux IAN 365198 Handleiding

29 November 2024
Livarno Lux

Livarno Lux IAN 367074 Handleiding

29 November 2024
Livarno Lux

Livarno Lux HG00701 Handleiding

29 November 2024
Livarno Lux

Livarno Lux IAN 337273 Handleiding

29 November 2024