A8430
器件描述：White LED Driver Constant Current Step-up Converter
器件厂商：ALLEGRO [Allegro MicroSystems]
文件大小：329.06KB，共10页
Sponsor by e络盟器件资料摘要：
Data Sheet26185.300C
A8430
White LED Driver Constant Current Step-up Converter
Use the following complete part number when ordering:
AB SO LUTE MAX I MUM RAT INGS
SW Pin ................................................–0.3 V to 36 V
Remaining Pins .................................. –0.3 V to 10 V
Ambient Operating Temperature, T
A
....... –40°C to 85°C
Junction Temperature, T
J(max)
...............................150°C
Storage Temperature, T
S
.................... –55°C to 150°C
A8430 MLPD
null Output voltage up to 36 V
null 2.5 V to 10 V input
null Drives up to 4 LEDs at 20 mA from a 2.5 V supply
null Drives up to 5 LEDs at 20 mA from a 3 V supply
null 1.2 MHz switching frequency
null 300 mA switch current limit
null 1 µA shutdown current
FEATURES
null LED backlights
null Portable battery-powered equipment
null Cellular phones
null PDAs (Personal Digital Assistant)
null Camcorders, personal stereos, MP3 players, cameras
null Mobile GPS systems
APPLICATIONS
The A8430 is a noninverting boost converter that steps-up the input
voltage, to provide a programmable constant current output at up to
36 V for driving white LEDs in series. Driving LEDs in series ensures
identical currents and uniform brightness. Up to four white LEDs can
be driven at 20 mA from a single cell Li-ion or a multicell NiMH power
source. Up to seven white LEDs can be driven by increasing the supply
voltage up to 10 V.
The A8430 incorporates a power switch and feedback sense amplifier
to provide a solution with minimum external components. The output
current can be set by adjusting a single external sense resistor and can
be varied with a voltage or filtered PWM signal when dimming control
is required. The high switching frequency of 1.2 MHz allows the use of
small inductor and capacitor values.
The A8430 is provided in a 5-pin 3 mm x 3 mm MLP package (part
number suffix EK), that has a nominal height of only 0.75 mm. The
lead-free version (part number suffix EK-T) has 100% lead-free matte
tin leadframe plating.
51
2
3 4
SW
GND
FB
VIN
EN
Part Number Package Description
A8430EEK 5-pin, MLPD Surface Mount
A8430EEK-T 5-pin, MLPD Lead-Free, Surface Mount
R
θJA
= 50 °C/W, see note 1, page 2
Approximate actual size
Same pad footprint as SOT-23-5
A8430
White LED Driver Constant Current Step-up Converter
Use the following complete part number when ordering:
AB SO LUTE MAX I MUM RAT INGS
SW Pin ................................................–0.3 V to 36 V
Remaining Pins .................................. –0.3 V to 10 V
Ambient Operating Temperature, T
A
....... –40°C to 85°C
Junction Temperature, T
J(max)
...............................150°C
Storage Temperature, T
S
.................... –55°C to 150°C
A8430 MLPD
null Output voltage up to 36 V
null 2.5 V to 10 V input
null Drives up to 4 LEDs at 20 mA from a 2.5 V supply
null Drives up to 5 LEDs at 20 mA from a 3 V supply
null 1.2 MHz switching frequency
null 300 mA switch current limit
null 1 µA shutdown current
FEATURES
null LED backlights
null Portable battery-powered equipment
null Cellular phones
null PDAs (Personal Digital Assistant)
null Camcorders, personal stereos, MP3 players, cameras
null Mobile GPS systems
APPLICATIONS
The A8430 is a noninverting boost converter that steps-up the input
voltage, to provide a programmable constant current output at up to
36 V for driving white LEDs in series. Driving LEDs in series ensures
identical currents and uniform brightness. Up to four white LEDs can
be driven at 20 mA from a single cell Li-ion or a multicell NiMH power
source. Up to seven white LEDs can be driven by increasing the supply
voltage up to 10 V.
The A8430 incorporates a power switch and feedback sense amplifier
to provide a solution with minimum external components. The output
current can be set by adjusting a single external sense resistor and can
be varied with a voltage or filtered PWM signal when dimming control
is required. The high switching frequency of 1.2 MHz allows the use of
small inductor and capacitor values.
The A8430 is provided in a 5-pin 3 mm x 3 mm MLP package (part
number suffix EK), that has a nominal height of only 0.75 mm. The
lead-free version (part number suffix EK-T) has 100% lead-free matte
tin leadframe plating.
51
2
3 4
SW
GND
FB
VIN
EN
Part Number Package Description
A8430EEK 5-pin, MLPD Surface Mount
A8430EEK-T 5-pin, MLPD Lead-Free, Surface Mount
R
θJA
= 50 °C/W, see note 1, page 2
Approximate actual size
Same pad footprint as SOT-23-5