AX2020 Datasheet PDF - AXElite
| Part Number | AX2020 | |
| Description | 1A Step-down High Brightness LED Driver | |
| Manufacturers | AXElite | |
| Logo |  |
|
|
There is a preview and AX2020 download ( pdf file ) link at the bottom of this page. Total 11 Pages | ||
Preview 1 page No Preview Available !
AX2020
32V,1A Step-down High Brightness
LED Driver with 5000:1 Dimming
GENERAL DESCRIPTION
The AX2020 is a continuous conduction mode inductive step-down converter, designed
for driving single or multiple series connected LED efficiently from a voltage source higher
than the total LED chain voltage. The device operates from an input supply between 8V and
32V and provides an externally adjustable output current of up to 1A. Depending upon the
supply voltage and external components, the AX2020 can provide more than 15 watts of
output power. The AX2020 includes the power switch and a high-side output current sensing
circuit, which uses an external resistor to set the nominal average output current, and a
dedicated DIM input accepts a wide range of pulsed dimming. Applying a voltage of 0.3V or
lower to the DIM pin turns the output off and switches the device into a low current standby
state.
The AX2020 is available in SOT89-5L package.
FEATURES
- Simple low parts count
- Wide input voltage range: 8V to 32V
- Up to 1A output current
- Single pin on/off and brightness control using PWM
- Up to 1MHz switching frequency
- Typical 5% output current accuracy
- High-Side Current Sense
- Hysteretic Control: No Compensation
- Adjustable Constant LED Current
Axelite Confidential Materials, do not copy or distribute without written consent.
1/11
|
| |
 
AX2020
APPLICATION INFORMATION
OPERATION DESCRIPTION
The device, in conjunction with the coil (L1) and current sense resistor (RS), forms a
self oscillating continuous-mode buck converter.
When input voltage VIN is first applied, the initial current in L1 and RS is zero and there
is no output from the current sense circuit. Under this condition, the output of CS comparator
is high. This turns on an internal switch and switches the SW pin low, causing current to flow
from VIN to ground, via RS, L1 and the LED(s). The current rises at a rate determined by VIN
and L1 to produce a voltage ramp (VCSN) across RS. When (VIN-VCSN) > 150mV, the output of
CS comparator switches low and the switch turns off. The current flowing on the RS
decreases at another rate. When (VIN-VCSN) < 110mV, the switch turns on again and the
mean current on the LED is determined by ( 110 + 150 mV) / RS= 130mV / RS.
2
The high-side current-sensing scheme and on-board current-setting circuitry minimize
the number of external components while delivering LED current with ±5% accuracy, using a
1% sense resistor.
The AX2020 allow dimming with a PWM signal at the DIM input. A logic level below
0.3V at DIM forces AX2020 to turn off the LED and the logic level at DIM must be at least
2.0V to turn on the full LED current. The frequency of PWM dimming ranges from 100Hz to
more than 20 kHz.
The DIM pin is pulled high current approximately 70μA. It can be floated at normal
working. When a voltage applied to DIM falls below the threshold (0.3V nom.), the output
switch is turned off. The internal regulator and voltage reference remain powered during
shutdown to provide the reference for the shutdown circuit.
Additionally, to ensure the reliability, the AX2020 is built with a thermal shutdown (TSD)
protection and a thermal pad. The TSD protests the IC from over temperature (150°C). Also
the thermal pad enhances power dissipation. As a result, the AX2020 can handle a large
amount of current safely.
Setting nominal average output current with external resistor RS
The nominal average output current in the LED(s) is determined by the value of the
external current sense resistor (RS) connected between VIN and CSN and is given by:
IOUT = 0.130/RS (RS ≧ 0.16Ω)
This equation is valid when DIM pin is float. Actually, RS sets the maximum average
current which can be adjusted to a less one by dimming.
5/11
Axelite Confidential Materials, do not copy or distribute without written consent.
Rev.1.2 Oct.06, 2010
Preview 5 Page |
Part DetailsOn this page, you can learn information such as the schematic, equivalent, pinout, replacement, circuit, and manual for AX2020 electronic component. |
| Information | Total 11 Pages | |
| Link URL | [ Copy URL to Clipboard ] | |
| Download | [ AX2020.PDF Datasheet ] | |
Share Link :
Electronic Components Distributor
|
An electronic components distributor is a company that sources, stocks, and sells electronic components to manufacturers, engineers, and hobbyists. |
| SparkFun Electronics | Allied Electronics | DigiKey Electronics | Arrow Electronics |
| Mouser Electronics | Adafruit | Newark | Chip One Stop |
Featured Datasheets
| Part Number | Description | MFRS |
| AX2020 | The function is 1A Step-down High Brightness LED Driver. AXElite | |
| AX2021 | The function is 0.45A Step-down High Brightness LED Driver. AXElite | |
Semiconductors commonly used in industry:
1N4148 |
BAW56 |
1N5400 |
NE555 | | ||
Quick jump to:
AX20
1N4
2N2
2SA
2SC
74H
BC
HCF
IRF
KA | ||