BL8584 6-Channels WLED Linear Driver DESCRIPTION FEATURES The BL8584 is a CMOS based White/Blue LED driver with stand-alone capability. The driver is primarily designed for LED backlighting of LCD display powered by Li-ion battery With its high efficiency, low standby current and wide range of input supply voltage, the BL8584 is suitable for applications such as portable device display and keypad backlighting. There are six identical channels in BL8584, each of which can drive one LED by current rating of 20mA. • • • • • BL8584 is available with QFN 3X3-16 package • • TYPICAL APPLICATION PIN ASSIGNMENT • • APPLICATIONS BL8 BL8584 BLOCK DIAGRAM www.belling.com.cn 6-channels output 2.7 to 5.5V input range PWM dimming control LED sink current of 20mA Independent current sink circuit for each LED output Low standby current High accuracy current match on each channel 1 LCD screen backlights driver Mobile phone, portable device keypad backlights driver BL8584 6-Channels WLED Linear Driver MARKING INFORMATION ORDERING INFORMATION Product Classification Marking BL8584 □ 1 □ 2 □ 3 BL8584CJKTR Code 1 □ KC: Product Code LL: LOT No. KC N: FAB Code LLNYW Y: Year No. W: Week No. 2 □ 3 □ Description Temperature&Rohs: C: -40~85°C, Pb Free Rohs Std. Package type: JK: QFN 3X3 –16 Packing type: TR:Tape&Reel (Standard) Top view PIN DESCRIPTION Name D1-D6 EN VIN GND NC Function Description RGB or WLED Cathode Connection Pin Chip Enable and Dimming Control. Pin15 and Pin16 both are EN pins, they are shorted internally, so please don’t connect one of them to GND Power Supply Ground Not Connected ABSOLUTE MAXIMUM RATING Supply voltage –0.3V to 7V Voltage of LEDn, EN pin Maximum Junction Temperature Operating Ambient Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec) –0.3V to 7V 125°C –40°C to 85°C –40°C to 150°C 260°C Note: Exceed these limits to damage to the device. Note: Exposure to absolute maximum rating conditions may affect device reliability. RECOMMENDED OPERATING CONDITIONS Items Supply Voltage Range Operating Temperature www.belling.com.cn MIN 2.7 -25 2 MAX 5.5 85 Unit V °C BL8584 ELECTRICAL CHARACTERISTICS VCC=3.7V, Ta=25°C, No Load, Input: VEN=3.7V. (Unless otherwise noted) Conditions SPEC TYP Symbols Parameters VIL VIH IIL IIH VLEDL ILED ILEDn IQ ISTBY EN Pin “Low” Logic EN Pin “High” Logic 1.7 V V EN Pin “Low” Input Current -1 uA MIN EN Pin “High” Input Current LEDn Dropout Voltage LEDn Sink Current 18 LEDn Sink Current Deviation -5 MAX 0.4 1 Quiescent Current 100 20 500 Standby Supply Current VEN=”0” 0.5 Unit 22 uA mV mA 5 % 800 uA uA DETAILED DESCRIPTION BL8584 works with a wide range of supply voltage, from 2.7V to 6V. The forward voltage of commercial white/blue LED is in the range of 2.9V to 3.5V at a current level of 20mA. Proper selection of the LED to match the supply voltage can fully utilize the Li-ion battery. For example, there is 1% ~ 3 % power left in the Li-ion battery when its voltage reaches 3.275V. So a LED with a forward voltage value of 3.2V can use up to 99% of the battery power under normal working condition. When the voltage of the battery drops below 3.2V, the current through the LED (hence the brightness) starts to decrease. Due to its uniquely designed current regulator, BL8584 offers low output dropout and provide superior efficiency performance over standard Inductive boost type and capacitive charge pump type LED driver. The EN pin controls the on/off state of the device. A high level state turns on the device and a low level turns off the device, results in the low off state current. This pin needs to be terminated since a floating level of the EN pin will cause the instability of the device. The sink current has a constant value of 20mA. The brightness of the LED can be adjusted by controlling the duty cycle of the BL8584’s LEDn output. This can be accomplished by applying a PWM signal to the EN pin. In BL8584, the internal power on sequence presents a delay time of 6us from EN pin to LEDn pin. Hence, in order to modulate the output of LEDn in every cycle normally, the width of dimming signal applied EN pin have to be no less than 6us. For example, when a dimming signal of 20KHz is applied, the minimum range of dimming is about 12%, that is, the average output current on each channel is 2.4mA. www.belling.com.cn 3 BL8584 TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current vs Temperature (VCC=3.7V) 350 450 300 400 Quiescent Current (uA) Quiescent Current (uA) Quiescent Current vs Supply Current (Ta=25℃) 250 200 150 100 50 0 3.0 350 300 250 200 150 100 50 0 3.5 4.0 4.5 5.0 -40 -20 Supply Voltage (V) ILED vs Supply Voltage 20 20 LED Current (mA) ILED (mA) 25 18 16 14 10 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 0 0.01 Supply Voltage (V) ILED (mA) 20.2 20.2 20.1 20.1 20.0 20.0 19.9 19.9 19.8 19.8 19.7 75 100 125 Temperature (℃) www.belling.com.cn 100 120 140 0.1 1 LEDn Dropout Voltage (V) ILED vs Temperature (VCC=3.7V) 50 80 10 5 25 60 15 12 0 40 ILED vs LEDn Dropout Voltage (VCC=3.7V) 22 -25 20 Temperature (℃) (VCC=3.7V, VLEDn=3.2V) -50 0 4 10 BL8584 PACKAGE INFORMATION Package QFN3X3-16 www.belling.com.cn Devices per reel 5 3000 Unit mm