PAM2808 [PAM]
5W High Power HBLED Driver; 5W大功率高亮度LED驱动器
| 型号： | PAM2808 |
| 厂家： | 
POWER ANALOG MICOELECTRONICS |
| 描述： | 5W High Power HBLED Driver |
| 文件： | 总8页 (文件大小：165K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
PAM2808
5W High Power HBLED Driver
Features
General Description
The PAM2808 is a 5W high power HBLED driver
with 1.5A constant current. It features high
efficiency and low quiescent current,making it
ideal for battery powered applications.
n High Output Current Up to 1.5A
n Low Feedback Voltage:0.1V
n Stable with a Ceramic Output Capacitor
n Low Quiescent Current
n Open Load LED Protection
n Over Temperature Shutdown
n Low Temperature Coefficient
n Standard SOP-8(EP) Packages
n Pb-Free Package
The PAM2808 features over current protection
and over temperature shutdown. The PAM2808 is
stable with a ceramic output capacitor of 4.7μF or
higher.
PAM2808 is available in SOP-8(EP) package.
Applications
n High Bright LED Driver
n White LED Torch (Flashlight)
Typical Application Circuit
VIN
VOUT
VIN
VOUT
PAM2808
EN
FB
CO
4.7μF
GND
CIN
4.7μF
Rs
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
1
PAM2808
5W High Power HBLED Driver
Block Diagram
VIN
VOUT
OverCurrent
Shutdown
Thermal
Shutdown
EN
AMP
Reference
FB
GND
Pin Configuration & Marking Information
Top View
SOP-8(EP)
NC
1
2
3
8 NC
7
6
VIN
EN
VOUT
FB
V: Voltage Code
X: Internal Code
Y: Year
W: Week
5 NC
4
GND
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
2
PAM2808
5W High Power HBLED Driver
Absolute Maximum Ratings
These are stress ratings only and functional operation is not implied. Exposure to absolute
maximum ratings for prolonged time periods may affect device reliability. All voltages are with
respect to ground.
Input Voltage...............................................6.5V
Storage Temperature....................-65°C to 150°C
EN, FB, VOUT Pin Voltage
.................................................-0.3V to VIN+0.3V
Maximum Output Current......................PD/(VIN-VO)
Maximum Junction Temperature..................150°C
Lead Soldering Temperature (5sec)........... 300°C
Recommended Operating Conditions
Maximum Supply Voltage..............................6V
Junction Temperature Range........-40°C to 125°C
Ambient Temperature Range...........-40°C to 85°C
Thermal Information
Parameter
Symbol
Package
Maximum
Unit
Thermal Resistance
(Junction to Case)
Thermal Resistance
(Junction to Ambient)
θJC
SOP-8(EP)
11
°C/W
θJA
SOP-8(EP)
90
°C/W
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
3
PAM2808
5W High Power HBLED Driver
Electrical Characteristic
VIN=4.5V,TA=25°C, CIN=4.7μF, CO=4.7μF, unless otherwise noted.
PARAMETER
Input Voltage
SYMBOL
Test Conditions
MIN
TYP
MAX
UNITS
V
I N
2.5
6.0
V
V
FB Reference Voltage
VREF
0.1
330
Rs=0.3Ω
Rs=0.14Ω
Rs=0.1Ω
700
Output Current
IO
mA
1000
1500
Rs=0.067Ω
Over Temperature
Shutdown
OTS
OTH
150
40
OC
OC
Over Temperature
Hysteresis
EN Input HighThreshold
VEH
VEL
ISD
VIN=2.5V to 5V
VIN=2.5V to 5V
VEN=0V
1.5
V
V
EN Input Low Threshold
Shutdown Current
0.3
1
µA
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
4
PAM2808
5W High Power HBLED Driver
Typical Performance Characteristics
TA =25°C,CIN =4.7μF,Co=4.7μF,unless otherwise noted.
1. LED Current vs Input Voltage
2. Feedback Voltage vs Input Voltage
1400
120
1200
1000
800
100
80
60
40
20
0
600
400
1W
3W
2W
5W
200
0
1W
3W
2W
5W
3.0
3.5
4.0
4. 5
5.0
5.5
6.0
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Input Voltage(V)
Input Voltage(V)
3. Dropout Voltage vs LED Current
4. Start up
350
300
250
200
150
100
50
0
0
500
1000
1500
2000
LED Current (mA)
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
5
PAM2808
5W High Power HBLED Driver
Application Information
External Capacitor Requirements
In general, the maximum expected power
(PD(max)) consumed by a linear regulator is
computed as:
A 4.7µF or larger ceramic input bypass capacitor,
connected between VIN and GND and located
P
DMAX= VI(avg)-VO (avg) ×IO (avg)+VI(avg)×I(Q)
(
)
close to the PAM2808, is required for stability. A
4.7μF minimum value capacitor from VO to GND is
also required. To improve transient response,
noise rejection, and ripple rejection, an additional
1 0 µ F o r l a r g e r, l o w E S R c a p a c i t o r i s
recommended at the output. A higher-value, low
ESR output capacitor may be necessary if large,
fast-rise-time load transients are anticipated and
the device is located several inches from the
power source, especially if the minimum input
voltage of 2.5 V is used.
Where:
l VI (avg) is the average input voltage.
l VO(avg) is the average output voltage.
l IO(avg) is the average output current.
l I(Q) is the quiescent current.
The quiescent current is insignificant compared
to the average output current; therefore, the term
VI(avg) xI(Q) can be neglected. The operating junction
temperature is computed by adding the ambient
temperature (TA ) and the increase in temperature
due to the regulator' s power dissipation. The
temperature rise is computed by multiplying the
maximum expected power dissipation by the sum
of the thermal resistances between the junction
and the case (RθJC), the case to heatsink (RθCS),
and the heatsink to ambient (RθSA). Thermal
resistances are measures of how effectively an
object dissipates heat. Typically, the larger the
device, the more surface area available for power
dissipation so that the object’s thermal resistance
will be lower.
Regulator Protection
The PAM2808 features internal current limiting,
thermal protection and short circuit protection.
During normal operation, the PAM2808 limits
output current to about 2.5A. When current
limiting engages, the output voltage scales back
linearly until the over current condition ends.
While current limiting is designed to prevent
gross device failure, care should be taken not to
exceed the power dissipation ratings of the
package. If the temperature of the device
exceeds 150°C, thermal-protection circuitry will
shut down. Once the device has cooled down to
approximately 40°C below the high temp trip
point, regulator operation resumes.
Thermal Information
The amount of heat generates is:
PD=(VIN-VO)IO.
All integrated circuits have a maximum allowable
junction temperature (TJ max) above which
normal operation is not assured. A system
designer must design the operating environment
so that the operating junction temperature (TJ)
does not exceed the maximum junction
t e m p e r a t u r e ( T J m a x ) . T h e t w o m a i n
environmental variables that a designer can use
to improve thermal performance are air flow and
external heatsinks. The purpose of this
information is to aid the designer in determining
the proper operating environment for a linear
regulator that is operating at a specific power
level.
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
6
PAM2808
5W High Power HBLED Driver
Ordering Information
PAM2808X X X xxx X
Shipping Package
Output Voltage
Number of Pins
Package Type
Pin Configuration
Pin Configuration
B Type:
1. NC
Package Type
Number of Pins
Shipping Package
L: SOP-8(EP)
B: 8
R: Tape & Reel
2. VIN
3. EN
4. GND
5. NC
6. FB
7. VOUT
8. NC
Part Number
Marking
Package Type
MOQ & Shipping Pckage
P2808
XXXYW
PAM2808BLBR
SOP-8(EP)
2,500 Units/Tapes&Reel
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
7
PAM2808
5W High Power HBLED Driver
Outline Dimensions
SOP-8(EP)
Power Analog Microelectronics, Inc
www.poweranalog.com
08/2011 Rev1.0
8
相关型号：
©2020 ICPDF网 联系我们和版权申明