Microchip MIC3202-1 Manual


Læs gratis den danske manual til Microchip MIC3202-1 (19 sider) i kategorien Ikke kategoriseret. Denne vejledning er vurderet som hjælpsom af 13 personer og har en gennemsnitlig bedømmelse på 4.4 stjerner ud af 7 anmeldelser. Har du et spørgsmål om Microchip MIC3202-1, eller vil du spørge andre brugere om produktet?

Side 1/19
MIC3202/MIC3202-1
High-Brightness LED Driver with
Integrated MOSFET and High-Side
Current Sense
944-0800 • fax + 1 (408) 474-1000http://www.micrel.comMicrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408)
Septembe M9999-091710-A
r 2010
General Description
The MIC3202 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.
The MIC3202 is well suited for lighting applications
requiring a wide-input voltage range. The hysteretic control
gives good supply rejection and fast response during load
transients and PWM dimming. The high-side current
sensing and on-chip current-sense amplifier delivers LED
current with ±5% accuracy. An external high-side current-
sense resistor is used to set the output current.
The MIC3202 offers a dedicated PWM input (DIM) which
enables a wide range of pulsed dimming. High-frequency
switching operation of up to 1MHz allows the use of
smaller external components, minimizing space and cost.
The MIC3202 offers a frequency dither feature for low-EMI
applications.
The MIC3202 operates over a junction temperature from
− ° + °40 C to 125 C and is available in an 8-pin e-PAD SOIC
package.
A dither disabled version MIC3202-1 is also available in
the same package as the MIC3202.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
6V to 37V input voltage range
• > High efficiency ( 90%)
• ± 5% LED current accuracy
MIC3202: Dither enabled for low EMI
MIC3202-1: Dither disabled
High-side current sense (up to 1A)
Dedicated dimming control input
Hysteretic control (no compensation required)
Up to 1MHz switching frequency
Adjustable constant LED current
Over-temperature protection
• − ° + ° 40 C to 125 C junction temperature range
Applications
Architectural, industrial, and ambient lighting
LED bulbs
Indicators and emergency lighting
Street lighting
Channel letters
12V lighting systems (MR-16 bulbs, under-cabinet
lighting, garden/pathway lighting)
_________________________________________________________________________________________________________________________
Typical Application
MIC3202 Step-Down LED Driver
Efficiency
vs. Input Voltage
80
85
90
95
100
6 14 22 30 38
INPUT VOLTAGE (V)
EFFICIENCY (%)
I
LED
= 1A
L = 47uH
8LED6LED
4LED
2LED
Micrel, Inc. MIC3202/MIC3202-1
September 2010 2 M9999-091710-A
Ordering Information (1)
Part Number Marking Junction Temperature Range Package PWM
MIC3202YME MIC3202YME − +40°C to 125°C 8-Pin SOIC Dither
MIC3202-1YME MIC3202-1YME − +40°C to 125°C 8-Pin SOIC Non-Dither
Note:
1. YM® is a GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Pin Configuration
8-Pin ePAD SOIC
MIC3202/MIC3202-1
Pin Description
Pin
Number Pin Name Pin Function
1 VCC
Voltage Regulator Output. The VCC pin supplies the power to the internal circuitry. The VCC is the output
of a linear regulator which is powered from VIN. A 1µF ceramic capacitor is recommended for bypassing
and should be placed as close as possible to the VCC and AGND pins.
2 CS Current-Sense Input. The CS pin provides the high-side current sense to set the LED current using an
external sense resistor.
3 VIN
Input Power Supply. The VIN pin is the input supply pin to the internal circuitry and the positive input to
the current sense comparator. Due to the high frequency switching noise, a 1µF ceramic capacitor is
recommended to be placed as close as possible to VIN pin and the power ground (PGND) pin for
bypassing. Please refer to layout recommendations.
4 AGND Ground pin for analog circuitry. Internal signal ground for all low power sections.
5 EN
Enable Input. The EN pin provides a logic level control of the output. The voltage has to be 2.0V or higher
to enable the current regulator. the DIM input. When the EN pin is The output stage is also gated by
pulled low, the regulator goes to off state and the supply current of the device is greatly reduced (below
1µA).
6 DIM
PWM Dimming Input. The DIM pin provides the 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 at least 2.0V
or higher. DIM low disables the output, regardless of EN “high” state.
7 PGND
Power Ground pin for Internal Power FET. Power Ground (PGND) is the ground path for the high current.
The current loop for the power ground should be as small as possible and separate from the Analog
ground (AGND) loop. Refer to the layout considerations for more details.
8 LX
Drain of Internal Power MOSFET. The LX pin connects directly to the inductor and provides the switching
current necessary to operate in hysteretic mode. Due to the high frequency switching and high voltage
associated with this pin, the switch node should be routed away from sensitive nodes.
EP GND Connect to PGND.


Produkt Specifikationer

Mærke: Microchip
Kategori: Ikke kategoriseret
Model: MIC3202-1

Har du brug for hjælp?

Hvis du har brug for hjælp til Microchip MIC3202-1 stil et spørgsmål nedenfor, og andre brugere vil svare dig