NCP5608
Multiple LED Charge Pump
Driver
The NCP5608 is a high efficiency boost converter operating in
current loop, based on a charge pump multi mode, to drive White
LED. The current mode regulation allows a uniform and
programmable brightness of the LEDs. The chip has been optimized
for small ceramic capacitors, capable to supply up to 2.0 W output
power.
Features
http://onsemi.com
MARKING
DIAGRAM
24
1
24 PIN TQFN (4x4)
MT SUFFIX
CASE 511AA
A
L
Y
W
G
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
NCP
5608
ALYW
G
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
2.7 to 5.5 V Input Voltage Range
Up to 500 mA Output Current
Capable to Drive 8 LED
Multi Mode Charge Pump Based Converter
I2C Serial Link Protocol
Consistent High Efficiency
Independently Block Programmable Output Currents
Programmable 3 or 4 Operating Backlight LED at Zero Extra
Losses
Constant Output Current Regulation
Built−in Dimming Function
Tight Automatic LED Current Matching
Thermal Shutdown Protection
Low Battery Return Noise
This is a Pb−Free Device*
PIN CONNECTIONS
PVbat
19
18 V
OUT
17 C1P
16 C1N
15 LED8
14 LED7
13 PGND
7
LED1
8
LED2
9
LED3
10
LED4
11
LED5
12
LED6
Shipping
†
4000 / Tape & Reel
AVbat
C3N
C2N
20
C3P
22
C2P
21
24
AGND 1
IREFFL 2
IREFBK 3
SDA 4
SCL 5
CCMP 6
23
Typical Applications
LED Display Back Light Control
Keyboard Back Light
High Power Photo Flash
Multiple Displays
ORDERING INFORMATION
Device
NCP5608MTR2G
Package
TQFN24
(Pb−Free)
*For additional information on our Pb−Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques Reference
Manual, SOLDERRM/D.
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specification
Brochure, BRD8011/D.
©
Semiconductor Components Industries, LLC, 2006
1
June, 2006 − Rev. 1
Publication Order Number:
NCP5608/D
NCP5608
PIN FUNCTION DESCRIPTION
Pin
1
Symbol
AGND
Type
GROUND
Description
This pin is the NCP5608 analog ground and shall be connected to the system ground. Care
must be observed to minimize the total parasitic inductance between the pin and the ground
plane.
This pin is used to set up the current reference for the FLASH output currents (LED5 to
LED8). The reference current is derived from the internal bandgap voltage to ground by
means of an external resistor. (Note 1)
This pin is used to set up the current reference for the BACK LIGHT output currents (LED1
to LED4). The reference current is derived from the internal bandgap voltage to ground by
means of an external resistor. (Note 1)
This pin, associated with the SCL signal, carries the DATA signal to set up the selected
output LED current.
The DATA signal is built with a single SDA line to support the I2C protocol.
This is the clock signal associated with the SDA pins. The pin carries the standard CLOCK
signal to operate the I2C protocol.
This pin is connected to the internal I2C bias network and must be either left open, or
bypassed to ground by a 10 nF ceramic capacitor when the I2C voltage drops below 1.8 V.
Such a capacitor compensate the voltage drop during normal operation, keeping in mind it is
not mandatory when the I2C voltage is 1.8 V and above.
This pin sinks to ground the current flowing into the first LED, and is intended to be used in
backlight application. The current is limited to 30 mA max. (Note 2)
This pin sinks to ground the current flowing into the second LED, and is intended to be used
in backlight application. The current is limited to 30 mA max. (Note 2)
This pin sinks to ground the current flowing into the third LED, and is intended to be used in
backlight application. The current is limited to 30 mA max. (Note 2)
This pin sinks to ground the current flowing into the fourth LED, and is intended to be used
in backlight application. The current is limited to 30 mA max. (Note 2)
On the other hand, LED4 can be disconnected when only three LEDs are used in the
backlight application. (Table 1)
This pin sinks to ground the current flowing into the fifth LED (100 mA max), and is intended
to be used in Flash application. (Note 2)
This pin sinks to ground the current flowing into the sixth LED (100 mA max), and is
intended to be used in Flash or high power application. (Note 2)
This pin provides the ground reference for the power elements and must be connected to
the system ground by a heavy track. Using the ground plane technique is strongly
recommended. Care must be observed to minimize the total parasitic inductance between
the pin and the ground plane.
This pin sinks to ground the current flowing into the seventh LED (100 mA max), and is
intended to be used in flash or high power application. (Note 2)
This pin sinks to ground the current flowing into the eighth LED (100 mA max), and is
intended to be used in flash or high power application. (Note 2)
This pin is the second side of the C1 fly capacitor.
This pin is the first side of the C1 fly capacitor.
This pin provides the output power to the external LED. Since the regulation is based on a
current loop, the voltage will varies as the output current varies in the application. The Vout
pin must be bypassed to GND by a 4.7
mF
ceramic capacitor. (Note 3)
This pin provides the supply voltage to the charge pump converter. The pin must be
connected to the AVbat supply source and bypassed to GND by a 10
mF/16
V ceramic
capacitor. (Note 3) Using a power plane is recommended.
This pin is the second side of the C2 fly capacitor.
This pin is the first side of the C2 fly capacitor.
This pin is the second side of the C3 fly capacitor.
This pin is the first side of the C3 fly capacitor.
This pin provides the supply voltage to the analog and digitals blocks. The pin must be
connected to the PVbat supply source and bypassed to GND by a 1
mF/16
V ceramic
capacitor. (Note 3) Using a power plane is recommended.
2
IREFFL
OUTPUT, ANALOG
3
IREFBK
OUTPUT, ANALOG
4
SDA
INPUT, DIGITAL
5
6
SCL
CCMP
INPUT, DIGITAL
ANALOG, INPUT
7
8
9
10
LED1
LED2
LED3
LED4
INPUT, POWER
INPUT, POWER
INPUT, POWER
INPUT, POWER
11
12
13
LED5
LED6
PWRGND
INPUT, POWER
INPUT, POWER
POWER
14
15
16
17
18
LED7
LED8
C1N
C1P
VOUT
INPUT, POWER
INPUT, POWER
POWER
POWER
OUTPUT, POWER
19
PVBAT
INPUT, POWER
20
21
22
23
24
C2N
C2P
C3P
C3N
AVbat
POWER
POWER
POWER
POWER
INPUT, POWER
1. To achieve a good accuracy of the LED current, 1% tolerance resistor, with 100 ppm stability, or better, shall be used. The reference current
is internally mirrored and sized according to the programmed value for a given external LED.
2. Total DC−DC output current is limited to 500 mA.
3. Ceramic X7R, ESR < 50 mW ESL < 0.5 nH, SMD types capacitors are mandatory to achieve the Iout specifications. On the other hand, care
must be observed to take into account the DC bias impact on the capacitance value; see ceramic capacitor manufacturer data sheets.
http://onsemi.com
4
NCP5608
MAXIMUM RATINGS
Rating
Power Supply
Digital Input Voltage
Digital Input Current
ESD Capability (Note 4)
Human Body Model (HBM)
Machine Model (MM)
QFN24 Package
Power Dissipation @ T
A
= +85°C (Note 5)
Thermal Resistance, Junction−to−Air (according to JEDEC/EIA JESD51−12)
Operating Ambient Temperature Range
Operating Junction Temperature Range
Maximum Junction Temperature
Storage Temperature Range
Latchup Current Maximum Rating (per JEDEC standard: JESD78) Class II
Moisture Sensitivity Level (Note 6)
Symbol
V
bat
SDA, SCL
−
V
ESD
2.0
200
P
D
R
qJA
T
A
T
J
T
Jmax
T
stg
−
MSL
250
160
−40 to +85
−40 to +125
+150
−65 to +150
"100
1
kV
V
mW
°C/W
°C
°C
°C
°C
mA
−
Value
7.0
−0.3
v
V
in
v
V
BAT
+ 0.3
1.0
Unit
V
V
mA
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
4. This device series contains ESD protection and exceeds the following tests:
Human Body Model (HBM): JESD22−A114.
Machine Model (MM): JESD22−A115.
5. The maximum package power dissipation limit must not be exceeded.
6. Moisture Sensitivity Level (MSL): per IPC/JEDEC standard: J−STD−020A.
http://onsemi.com
5
京公网安备 11010802033920号
EEWORLD
