APE8872 Format - Advanced Power Electronics Corp

Advanced Power
Electronics Corp.
APE8872
1.6X LINEAR FAN DRIVER WITH VO FULLY ON CONTROL
FEATURES
DESCRIPTION
Low Dropout Voltage: 150mV@0.5A
VO Follows 1.6 times of VSET
FON Pin to Turn VO Fully On
Stable with Low ESR Ceramic Capacitors
Current-Limit and Thermal Shutdown Protection
SOP-8 Pb-Free Package
The APE8872 is a low dropout linear regulator which is
designed to power a DC fan and delivers up to 500mA
output current. The output voltage follows the 1.6 times of
VSET voltage and typical dropout voltage is only 150mV
(typical) at 500mA output current. The V SET voltage must be
larger than 1V to guarantee V O 1.6 times of VSET. A FON pin
turns VO output fully on when given low. The features of
current limit (with fold back current) and over temperature
protection protect the device against current over-loads and
over temperature. The APE8872 is available in a SOP-8
package.
TYPICAL APPLICATION
U1
VIN=5V
2
VSET
C1
FON
4
1
2.2uF
Vo=1.6 X VSET
3
VO
VIN
VSET
GND
FON
5,6,7,8
C2
2.2uF
FAN
APE8872
PACKAGE ORDERING INFORMATION
APE8872X
8872M
Y WW SSS
Package Type
M : SOP-8L
Data and specifications subject to change without notice
Part number
ID code: internal
WW: 01~52
Year: 8 : 2008
1
200808284
Advanced Power
Electronics Corp.
APE8872
ABSOLUTE MAXIMUM RATINGS
VIN Supply Voltage (VIN) ……………………………… -0.3 to 7 V
FON Input Voltage (VFON) …………………………… -0.3V to VIN
VSET Voltage (VSET) …………………………………… -0.3V to VIN
Power Dissipation (PD) ……………………………… Internally limited
Storage Temperature Range (T ST) ………………… -65 to +150°C
Junction Temperature Range (T J) …………………
-40 to 125°C
Operating Temperature Range (T OP) ……………… -40 to +85°C
Thermal Resistance from Junction to case (R thjc)
20°C/W
Thermal Resistance from Junction to ambient (Rthja)
60°C/W
Note: Rthja is measured with the PCB copper area approximately 1.5 in 2 (Multi-layer)
PACKAGE INFORMATION
FON
1
VIN
2
VO
3
VSET
4
( Top View )
8 GND
APE8872
7 GND
6 GND
5 GND
SOP-8L
ELECTRICAL SPECIFICATIONS
(VSET = 2V, VIN = 5V, Io = 0.5A, CIN=COUT=2.2uF, TA=25°C unless otherwise specified)
Parameter
SYM
VIN Supply Voltage Range
VIN
Quiescent Current
ICCQ
Output Voltage/VSET Voltage
VO/VSET
TEST CONDITION
VO=5V, No Load
VIN=5.5V, VSET=1V~3.2V
MIN
UNITS
TYP
MAX
4.5
-
5.5
V
-
1
-
mA
1.552
1.6
1.648
V/V
Line Regulation
VIN=4.5V to 5.5V
-
0.2
0.5
%
Load Regulation
IO=10mA ~ 0.5A
-
0.2
0.5
%
IO =0.5A, VSET=3.4V
-
300
400
mΩ
-
1.5
3
A
Vo<0.6V
-
0.5
3
A
-
1
-
V
nA
Output Resistance
RDS(ON)
Current Limit
ILimt
Short Circuit Current
IShort
Minimum VSET Voltage
VSET
VSET Pin Current
FON Pin Logic Threshold Voltage
-
80
200
VFON-H
ISET
Normal Operating
2
-
-
VFON-L
Regulator Fully On
-
-
0.8
FON Pin Bias Current
IFON
Thermal shutdown Temp
TSD
Thermal Shutdown Hysteresis
FON=0V
V
-
1.5
10
uA
-
150
-
°C
-
40
-
°C
2
Advanced Power
Electronics Corp.
APE8872
PIN DESCRIPTIONS
PIN SYMBOL
PIN DESCRIPTION
GND
GND pin
VIN
IC power supply pin
VO
Output Pin. Its voltage is 1.6 times of VSET
This pin sets the output voltage. Its voltage must be larger than 1V to guarantee
VSET
VO 1.6 times of VSET
FON Input. Pulling this pin below 0.4V turns the regulator fully on. Internally pulled high.
FON
BLOCK DIAGRAM
VO
VIN
Current Limit and
Short Protection
- +
Error
Amp
Thermal
Shutdown
FON
VO Fully On
Logic
GND
VSET
FUNCTION DESCRIPTION
Output Voltage Regulation
The Output Voltage is set by VSET voltage. VO output voltage follows the 1.6 times of VSET
voltage until it reaches VIN voltage.
Current-Limit
The APE8872 monitors the current via the output PMOS and limits the maximum current to
prevent load and APE8872 from damages during overload or short circuit conditions.
Short Current Protection
When the output voltage drops below 0.6V (typical), which is caused by over load or short
circuit, the fold back current limit circuitry limits the output current to 500mA. The fold back current
limit is used to reduce the power dissipation during short circuit condition.
Thermal Shutdown
A thermal shutdown circuit limits the junction temperature of APE8872. When the junction
temperature exceeds +150°C, a thermal sensor turns off the output PMOS, allowing the device to
cool down. The regulator regulates the output again through initiation of a new soft-start cycle after
the junction temperature cools by 40°C, resulting in a pulsed output during continuous thermal
overload conditions.
3
Advanced Power
Electronics Corp.
APE8872
APPLICATION INFORMATION
Capacitor Selection
Normally, use a 2.2uF capacitor on the input and a 2.2uF capacitor on the output of the
APE8872. In order to insure the circuit stability, the proper output capacitor value should be larger
than 1uF. With X5R and X7R dielectrics, 2.2uF is sufficient at all operating temperatures.
Thermal Considerations
The APE8872 series can deliver a current of up to 500mA over the full operating junction
temperature range. However, the maximum output current must be dated at higher ambient
temperature to ensure the junction temperature does not exceed 125°C. With all possible
conditions, the junction temperature must be within the range specified under operating conditions.
Power dissipation can be calculated based on the output current and the voltage drop across
regulator.
PD = (VIN - VO) IO
The final operating junction temperature for any set of conditions can be estimated by the
following thermal equation:
PD (MAX) = (TJ (MAX) - TA) / Rthja
Where TJ (MAX) is the maximum junction temperature of the die (125° C) and TA is the maximum
ambient temperature. The junction to ambient thermal resistance (Rthja) for SOP-8L package at
recommended minimum footprint is 60°C/W. Visit our website in which “Recommended Footprints
for Soldering Surface Mount Packages” for detail.
PCB Layout
1. Please place the input capacitors close to the VIN
2. Ceramic capacitors for load must be placed near the load as close as possible
3. To place APE8872 and output capacitors near the load is good for performance.
4. Large current paths that VIN and Output lines must have wide tracks.
5. GND connect large copper area can reduced IC temperature.
4
ADVANCED POWER ELECTRONICS CORP.
Package Outline : SO-8
D
Millimeters
8
7
6
5
E1
1
2
3
4
e
B
E
SYMBOLS
MIN
NOM
MAX
A
1.35
1.55
1.75
A1
0.10
0.18
0.25
B
0.33
0.41
0.51
c
0.19
0.22
0.25
D
4.80
4.90
5.00
E
5.80
6.15
6.50
E1
3.80
3.90
4.00
e
1.27 TYP
G
0.254 TYP
L
0.38
-
0.90
α
0.00
4.00
8.00
A
A1
G
1.All Dimension Are In Millimeters.
2.Dimension Does Not Include Mold Protrusions.
Part Marking Information & Packing : SO-8
Part Number
8872M
YWWSSS
Package Code
Date Code (YWWSSS)
Y:Last Digit Of The Year
WW:Week
SSS:Sequence
5