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BELLING |
BL8587
High Efficiency 1×/1.5× Charge Pump 4-Channels LED Driver
DESCRIPTION
BL8587 is a low noise, high efficiency, and
constant frequency charge pump DC/DC
converter for white LED application. The
operation frequency is 1MHz.
BL8587 works in load switch (1×) and
fractional (1.5×) modes with four independent
control outputs, each channel can provide
20mA constant current precisely from a 2.8V
to 5.5V supply. Only two external 1µF and
two 0.47µF capacitors are required to build a
compact and low-cost power supply solution.
BL8587 uses EN pin for simple on/off control
and single wire serial pulse dimming in 16
steps. A low current shutdown feature
disconnects the load from VIN and reduces
quiescent current to less than 1µA.
FEATURES
• Input range: 2.8-5.5V
• ±1% LED current accuracy
• 20mA driver capacity each channel
• Auto 1×/1.5× mode switchover
• PWM dimming control
• Serial-pulse dimming control in linear 16
steps
• Short-circuit protection
• Thermal shutdown
• 1MHz constant switching frequency
• 3mm×3mm QFN package
APPLICATION
• Programmable Current Sinks
• White LED Backlighting
• Cell Phones and Smart phones
• PDAs, Digital Cameras, and Camcorders
• Color (RGB) Lighting
TYPICAL APPLICATION CIRCUIT
BL8587
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BL8587
PIN DISCRIPTIONS
Pin No.
1
2
3
4
5
6
7
8
Symbol
NC
NC
D4
D3
D2
D1
GND
VOUT
9 C2+
10 C1+
11 C1-
12 C2-
13 VIN
14 PGND
15 NC
16 EN
Description
No connection
No connection
Channel 4 sink current input
Channel 3 sink current input
Channel 2 sink current input
Channel 1 sink current input
Signal ground
Charge pump output to drive load circuit, a 1µF capacitor should be used to short
this pin to ground.
Flying capacitor 2 positive terminal. Connect a 1µF capacitor between C2+ and
C2-.
Flying capacitor 1 positive terminal. Connect a 1µF capacitor between C1+ and
C1-.
Flying capacitor 1 negative terminal.
Flying capacitor 2 negative terminal.
Power supply input, a 1µF capacitor is required to connect this pin to ground.
Power ground
No connection
Enable pin and can use this pin to program the sink current.
PIN CONFIGURATION
NC 1
EN
16
NC PGND VIN
15 14 13
12 C2-
NC 2
11 C1-
D4 3
10 C1+
D3 4
9 C2+
5678
D2 D1 GND VOUT
Top view QFN 3mm×3mm
Marking :
LG: Product code
YY: LOT NO.
N: Fab code
ZZ: Date code
ORDERING INFORMATION
Product NO Ordering Number Pin Package
BL8587
BL8587CJKTR
3*3 QFN-16
Devices per
reel
3000
Temperature range & Rohs
-40~85°C & Pb free
ABSOLUTE MAXIMUM RATING
Item
VIN
Iomax
TJ
Description
Input supply voltage
Maximum load current
Operating junction temperature range
Value
-0.3-6
100
-40-150
Unit
V
mA
°C
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