UNISONIC TECHNOLOGIES CO., LTD P3576

UNISONIC TECHNOLOGIES CO., LTD
P3576
LINEAR INTEGRATED CIRCUIT
50KHz, 2A PWM BUCK DC/DC
CONVERTER

DESCRIPTION
The UTC P3576 series is a step-down switching regulator which
is able to provide 2A output current. The available versions of output
voltage are 2.5V, 3.3V, 5V, 12V and adjustable.

FEATURES
* Output load current: 2A
* Adjustable version output voltage range, 1.23V ~ 38.5V±4%
* Operating voltage can be up to 40V
* Low power standby mode
* High efficiency
* Internal current and thermal limit
* Built-in Switching Transistor On Chip.

ORDERING INFORMATION
Ordering Number
P3576G-xx-S08-R
Note: xx: Output Voltage, Refer to Marking Information
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Copyright © 2014 Unisonic Technologies Co., Ltd
Package
SOP-8
Packing
Tape Reel
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P3576
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LINEAR INTEGRATED CIRCUIT
MARKING INFORMATION
PACKAGE
VOLTAGE CODE
SOP-8
15 : 1.5V
33 : 3.3V
50 : 5.0V
AD: ADJ
MARKING
PIN CONFIGURATION
VCC
1
8
VSS
SW
2
7
VSS
FB
3
6
VSS
EN
4
5
VSS
PIN DESCRIPTION
PIN NO.
1
2
3
4
5~8
PIN NAME
VCC
SW
FB
EN
VSS
DESCRIPTION
Operating voltage input
Switching output
Output voltage feedback control
ON/OFF Shutdown
GND pin
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LINEAR INTEGRATED CIRCUIT
BLOCK DIAGRAM
EN
200mV
VCC
220mV
Current
Source
Bias
1.235V
Reference
2.5V
Regulator
Start
Up
50kHZ
OSC.
FB
+
COMP.
Current
Limit
COMP.
+
R2
+
AMP
COMP.
+
COMP.
-
Control
+
Driver
2A
Switch
R1
SW
Thermal
Shutdown
VSS
ADJ : R2=0Ω, R1=OPEN
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LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUM RATING (TA=25°C, unless otherwise specified )
PARAMETER
SYMBOL
RATINGS
UNIT
Supply Voltage
VCC
+45
V
ON/OFF Pin Input Voltage
VEN
-0.3 ~ 40
V
Feedback Pin Voltage
VFB
-0.3 ~ 12
V
Output Voltage to Ground
VOUT
-0.8
V
Operating Supply Voltage
VOP
+4.5 ~ +40
V
Power Dissipation
PD
Internally Limited
W
Junction Temperature
TJ
+125
°C
Operating Temperature
TOPR
-40~+125
°C
Storage Temperature
TSTG
-65 ~ +150
°C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
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THERMAL DATA
PARAMETER
SYMBOL
RATINGS
UNIT
Junction to Ambient
θJA
60
°С/W
Junction to Case
θJC
20
°С/W
Note: θJA is measured with the PCB copper area(need connect to SW pins) of approximately 1.5 in2(Multi-layer).
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ELECTRICAL CHARACTERISTICS (TA=25°C, unless otherwise specified, VCC=12V for 3.3V, 5V,
adjustable version and VCC=18V for the 12V version. ILOAD=0.2A.)
PARAMETER
Quiescent Current
Feedback Bias Current
ADJ
Shutdown Supply Current
Oscillator Frequency
ADJ
Oscillator Frequency of
Short Circuit Protect
Fixed
MAX
Duty Cycle
MIN
SYMBOL
TEST CONDITIONS
MIN TYP MAX
IQ
VFB=12V force driver off
4
8
IFB
VFB=1.3V
-10
-50
ISD
EN pin=5V, VCC=40V
100 200
fOSC
44
50
56
VFB<0.5V
25
fSCP
VOUT <VOUT*40%
25
DC
VFB=0V force driver ON
100
DC
VFB=12V force driver OFF
0
Pear current, No outside circuit
2.5
Current Limit
ICL
VFB=0V force driver on
Load Regulation(∆VOUT /VOUT)
∆VOUT IOUT=0.2 ~ 2A
0.6
1.2
IOUT=2A, No outside circuit
1.2
1.4
Saturation Voltage
VSAT
VFB=0V force driver on
No outside circuit VFB=12V force driver off
-200
SW pin Leakage SW pin=0V
ISWL
Current
SW pin=-0.8V
VCC=40V force driver off
-5
Low
VIL
regulator ON
1.3
0.6
EN pin Logic Input
Threshold Voltage
High
VIH
regulator OFF
2.0
1.3
EN pin Logic Input Current
IH
VEN=2.5V (OFF)
-0.1
-10
EN pin Input Current
IL
VEN=0.5V (ON)
-0.01
-1
Thermal shutdown Temp
TSD
135
ADJ
ILOAD=0.2A, VOUT programmed for 3.3V
1.193 1.23 1.267
3.3V
ILOAD=0.2A
3.20 3.30 3.40
Output Feedback Voltage
VFB
5.0V
ILOAD=0.2A
4.85 5.00 5.15
12V
ILOAD=0.2A
11.64 12.0 12.36
79
ADJ
VCC=12V, ILOAD=2A
3.3V
VCC=12V, ILOAD=2A
80
Efficiency
η
5.0V
VCC=12V, ILOAD=2A
84
12V
VCC=15V, ILOAD=2A
90
UNISONIC TECHNOLOGIES CO., LTD
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UNIT
mA
nA
μA
KHz
KHz
KHz
%
%
A
%
V
μA
mA
V
V
μA
μA
°C
V
%
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LINEAR INTEGRATED CIRCUIT
TYPICAL APPLICATION CIRCUIT
VIN=12V
L1
1
47μH
U1
1
2
C2
0.1μF
C1
470μF
3
4
VOUT=5.0V/2A
2
VCC
VSS 8
SW
VSS 7
FB
VSS 6
EN
VSS 5
R1
4.7K
D1
3A/40V
C3
470μF
C6
0.1μF
R2
1.5K
UTC P3576
(1) Adjustable Output Voltage Version
VIN=12V
L1
1
33μH
U1
1
2
C1
470μF
C2
0.1μF
C4
0.1μF
3
4
R3
100K
VOUT=2.5V/2A
2
VCC
VSS 8
SW
VSS 7
6
FB
VSS
EN
VSS 5
R1
1.8K
D1
2A/40V
C3
470μF
C6
0.1μF
R2
1.8K
UTC P3576
ON/OFF
(2) Adjustable Output Voltage Version With Delayed Startup
VOUT=VFB×(1+R1/R2), VFB=1.23V, R2=0.47K ~ 3K
Table 1 Resistor select for output voltage setting
VOUT
R2
1.5K
5V
1.8K
1.5K
3.3V
1.8K
2.5V
1.8K
1.8V
1.8K
VOUT
VIN=12V
VIN=24V
2.5V
33μH
33μH
L1 recommend value (IOUT=2A)
3.3V
33μH
33μH
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R1
4.7K
5.6K
2.5K
3.0K
1.8K
0.82K
5V
47μH
47μH
12V
NA
68μH
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LINEAR INTEGRATED CIRCUIT
TYPICAL APPLICATION CIRCUIT (Cont.)
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
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