DONGWOON DW8505A Low Dropout Linear LED Constant Current Driver IC | 100mA Adjustable/SOT23-5L/Small Size Backlight Dedicated | Replacement for BCR401W/BCR420U/DW8506
DW8505A Core Highlights: 5~40V Wide Input Voltage | 0~100mA Adjustable Constant Current | 0.1V@60mA Ultra Low Dropout | Built-in Thermal Derating Protection | Support PWM Dimming | SOT23-5L Package | No EMI Interference | Direct PIN to PIN Replacement for BCR401W/BCR420U/DW8506
Keywords:DW8505A, DONGWOON, Korea Dongwoon Technology, DW8505A Agent, DW8505A Datasheet, 100mA Linear Constant Current Driver, SOT23-5L, PWM Dimming LED Driver, Low Dropout Constant Current IC, Backlight Driver, Indicator Lighting Driver, DW8505A Replace BCR401W, DW8505A Replace BCR420U, DW8505A Replace DW8506
Product Description:DW8505A is an instant switch type low dropout linear LED constant current driver IC originally launched by DONGWOON Korea Dongwoon Technology. It supports 5~40V wide voltage input and max 100mA adjustable output. Built-in thermal derating protection, supports 0~100% PWM dimming, current set by single resistor, minimal peripheral circuit and no EMI interference. It is specially designed for LED bulbs, indicator decorative lighting, panel backlight, RGB backlight, automotive lighting, general constant current source and other scenarios. It can directly PIN to PIN replace mainstream models such as BCR401W, BCR420U and DW8506, with higher constant current accuracy, lower dropout voltage and stronger reliability.
DW8505A Linear LED Constant Current Driver IC Core Advantages
● Wide input voltage 5~40V, compatible with 12V/24V industrial and backlight power supply system
● Output current 0~100mA adjustable, precise setting by single resistor, constant current accuracy ±3%
● Ultra low dropout voltage: 0.1V@60mA, lower heat generation and higher efficiency
● Built-in thermal derating protection, automatic current reduction at high temperature, safer long-term operation
● Support PWM dimming (≤30kHz), 0~100% flicker-free precise dimming
● Only one peripheral resistor required, minimal circuit, low cost and simple layout
● SOT23-5L ultra-small package, compact size, good heat dissipation and easy for SMT production
● No EMI interference, easily pass various safety and EMC certification tests
DW8505A Key Electrical Parameters | Datasheet Specifications
| Parameter Item | Typical Value | Unit |
| Input Voltage | 5~40 | V |
| Output Current | 0~100 | mA |
| Dropout Voltage | 0.1@60mA | V |
| Constant Current Accuracy | ±3% | -- |
| Thermal Derating Threshold | 140 | ℃ |
| Dimming Mode | PWM | -- |
| Package Type | SOT23-5L | -- |
DW8505A Pin Definition & Package Dimension | Pinout Diagram
| Pin No. | Pin Name | Function Description |
| 1 | EN | Output enable control pin, active high, PWM dimming, recommended ≤30kHz |
| 2 | GND | Ground |
| 3 | RS | Output current setting, connect external resistor to GND |
| 4 | VDD | Power supply voltage input |
| 5 | OUT | LED constant current output |
DW8505A Internal Circuit Block Diagram | Internal Structure
DW8505A Typical Application Circuit | Reference Design
DW8505A Application Scenarios | Applicable Fields
● LED bulbs, household lighting, small lighting equipment
● Indicator signs, advertising signage, decorative LED lighting
● Panel display, home appliance panel, general backlight lighting
● RGB backlight, colorful lighting, ambient light driver
● DC/DC, AC/DC matching constant current source, current regulator module
● Automotive interior light, daytime running light, signal light, vehicle lighting
● General constant current source, industrial control, instrument and equipment constant current power supply
DW8505A Compatible Replacement Models & Advantage Comparison
DONGWOON DW8505A can be directly PIN TO PIN replaced: DW8506, BCR401W, BCR420U
● Advantage 1: Wider operating voltage 5~40V, covering more industrial and backlight scenarios
● Advantage 2: Lower dropout voltage (0.1V@60mA), higher efficiency and lower heat generation
● Advantage 3: Built-in thermal derating protection, most similar competitors without this protection, higher reliability
● Advantage 4: Constant current accuracy ±3%, current more stable under temperature and voltage fluctuation
● Advantage 5: Support PWM dimming, BCR401W does not support dimming, wider application scope
DW8505A vs Competitors Parameter Comparison | Replacement Specs
| Item | DW8505A | DW8506 | BCR401W | BCR420U | Advantage Description |
| Brand | DONGWOON | DONGWOON | Infineon | Infineon | Stable original supply |
| Operating Voltage | 5~40V | 6.5~40V | ~18V | ~40V | Wider voltage range |
| Max Output Current | 100mA | 100mA | 60mA | 150mA | Flexible output matching |
| Dropout Voltage | 0.1V@60mA | 0.5V@50mA | 1.2V | 1.4V | Lower dropout & higher efficiency |
| Thermal Protection | Yes | Yes | No | No | Safer at high temperature |
| Constant Current Accuracy | ±3% | ±5% | ±10% | ±10% | Higher accuracy & more stable |
| PWM Dimming | Support | Not Support | Not Support | Support | More flexible dimming |
Demo Board Test Comparison
| DW8505A | DW8506 | BCR401W | BCR420U |
| EVB |  |  |  |  |
| RSET(20mA) | 36Kohm | 6.04Kohm | 80ohm | 100ohm |
Output Current Characteristics vs Output Voltage Variation
Test Condition: Input 12V, Output Current 20mA
| Item | DW8505A | DW8506 | BCR420U | BCR401W | Remark |
| Voltage Drop | 0.2V | 0.3V | 1V | 1.2V | 90% Standard of Output Current |
DW8505A (DW8506) allows multiple LED modules to be installed on the same 12VDC switching power supply, because the voltage dropout of DW8505A and DW8506 is lower than BCR401W and BCR420U.
Influence of Output Voltage Variation on IC Temperature Characteristics
Test Condition: Input 12V, Output Current 20mA
| Item | DW8505A | DW8506 | BCR420U | BCR401W |
| IC Temperature(℃) | 53.7 | 54.3 | 58.4 | 51.2 |
Influence of Temperature Variation on Output Current Characteristics
Test Condition: Input 12V, Output 20mA, Temperature -45℃~145℃
| LED Vf | DW8505A | DW8506 | BCR420U | BCR401W | Remark |
| 2.6V | 4.53~-5.84% | -1.82~3.41% | 10.64~-20.39% | 14.89~-17.30% | DW8505A/DW8506 with thermal derating |
| 3.2V | 4.42~-5.70% | -1.81~3.39% | 10.56~-20.42% | 14.81~-18.63% |
When DW8505A and DW8506 perform thermal derating protection at 125℃, the output current drops to 1/4 of the set value, thus reducing the heating level of the IC.
BCR420U/BCR401W have no thermal protection circuit.
Output Current Characteristics vs EN Pin Voltage Variation
Test Condition: Input 40V, Output 20mA, EN voltage variation
DW8505A can output constant current 20mA with variable EN pin voltage, while BCR420U cannot output constant current value.
The output current variation of DW8505A is -0.09% when EN pin voltage ranges from 5V~35V, while that of BCR420U is as high as 15.38%.
DONGWOON Korea Dongwoon Technology Linear Constant Current Solution Recommendation
| DW8501 | DW8502 | DW8505A | DW8506 | DW8506A | DW3505A |
| Input Voltage(V) | 5~40 | 5~40 | 5~40 | 6.5~40 | 6.5~40 | 5~40 |
| Output Current | ≤1.5A Adjustable | ≤2.5A Adjustable | ≤100mA Adjustable | ≤100mA Adjustable | Fixed 60mA | ≤300mA Adjustable |
| Dropout Voltage | Max.0.3V@300mA | Max.1V@1A | Max.0.1V@60mA | Max.0.5V@50mA | Max.0.6V@60mA | Max.0.2V@60mA |
| Dimming | PWM | PWM | PWM | -- | -- | PWM |
| Protection Function | Thermal Derating | Thermal Derating | Thermal Derating | Thermal Derating | Thermal Derating | Thermal Derating |
| Package | SOT223-5L/TO252-5L | TO263-5L/TO220-5L | SOT23-5L | SOT23-5L | WLCSP | SOT89-5L |
| Typical Circuit |  |  |  |  |  |  |
Authorized Agency & Service
GS-Micro Semiconductor (Shenzhen) Co., Ltd. is the official authorized agent of DONGWOON Korea Dongwoon Technology. We focus on promoting linear constant current driver and power management IC, providing complete datasheet, application solution, sample testing and technical after-sales support to help customers achieve mass production quickly.
Official Website: http://huimai2.com
