UTC P3596
150KH
Z
, 3A PWM STEP-DOWN DC/DC
CONVERTER
LINEAR INTEGRATED CIRCUIT
1
DESCRIPTION
The UTC
P3596
series is a step-down switching regulator able to
provide
3A
output current. The available output voltages are
3.3V,
5V, 12V, and an adjustable
output version.
TO-220B
FEATURES
*Output load current:
3A
*Adjustable version output voltage range, 1.23V ~ 37V±4%
*Operating voltage can be up to
40V
*Low power standby mode
*High efficiency
*Internal current and thermal limit
1
TO-220-5
1
TO-263-5
1
TO-252-5
*Pb-free plating product number: P3596L
PIN DESCRIPTION
PIN NO.
1
2
3
4
5
PIN NAME
Vin
Output
GND
FB (Feedback)
SD (Shutdown)
DESCRIPTION
Operating voltage input
Switching output
Circuit Ground
Output voltage feedback control
ON/OFF shutdown
UTC
UNISONIC TECHNOLOGIES CO., LTD.
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QW-R103-023,A
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UTC P3596
BLOCK DIAGRAM
LINEAR INTEGRATED CIRCUIT
ON / OFF
V
IN
Current
Source
bias
1.235V
Reference
2.5V
Regulator
Start
up
+
Comp
-
-
Comp
+
FB
+
Amp
-
Frequency
Compe-
nsation
-
Comp
+
Pre-driver
3A
Switch
Output
150kHz
OSC.
Thermal
Shutdown
Gnd
TYPICAL APPLICATION
(Fixed Output Voltage Versions)
FB
12V
DC Input
Vin
+
Cin
Capacitor
1
4
UTC
2
P3596 -5.0V
5
on / off
3
Gnd
D1
Schottky Diode
Output
L1
Inductor
+
Co
Capacitor
5.0V/3A
Output Load
UTC
UNISONIC TECHNOLOGIES CO., LTD.
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UTC P3596
ADJUSTABLE OUTPUT VOLTAGE VERSIONS
C
FF
R1
1k
+
UNREGULATED
DC INPUT
LINEAR INTEGRATED CIRCUIT
LOCATE THE PROGRAMMING RESISTORS NEAR
THE FEEDBACK PIN USING SHORT LEADS
KEEP FEEDBACK WIRING AWAY
FROM INDUCTOR FLUX
OUTPUT
2
ON/OFF
R2
4 FEEDBACK
UTC P3596-
ADJ
3 GND
5
L1
D1
+V
IN
1
+
REGULATED OUTPUT
+
L
O
C
OUT
A
D
C
IN
HEAVY LINES MUST BE KEPT SHORT AND USE
GROUND PLANE CONSTRUCTION FOR BEST RESULTS
Vout×(
R1
R1 + R2
) = Vref
Vout = Vref (1+
R2
R1
-1)
)
Where Vref = 1.23V
R2 = R1(
Vout
Vref
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Maximum Supply Voltage
Operating Voltage
ON/OFF Pin Input Voltage
Feedback Pin Voltage
Output Voltage to Ground (Steady State)
Power Dissipation
Maximum Junction Temperature
Temperature Range
Storage Temperature Range
SYMBOL
Vcc
Vopr
V
ON/OFF
V
FB
V
out
P
D
Tj
T
opr
T
stg
RATINGS
45
4.5 ~ 40
-0.3 ~ +25
-0.3 ~ +25
-1
Internally limited
+150
-40 ~ +125
-65 ~ +150
UNIT
V
V
V
V
V
mW
℃
℃
℃
UTC
UNISONIC TECHNOLOGIES CO., LTD.
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UTC P3596
ELECTRICAL CHARACTERISTICS
LINEAR INTEGRATED CIRCUIT
MIN
3.168
4.8
11.52
TYP
3.3
5.0
12.0
73
80
90
1.230
73
10
150
1.16
100
0
4.5
2
5
80
1.3
1.3
5
0.02
50
173
1.4
MAX
3.432
5.2
12.48
UNIT
V
V
V
%
%
%
V
%
nA
kHz
V
%
6.9
50
30
10
200
0.6
15
5
A
μA
mA
mA
μA
(T
j
=25℃, V
IN
=12V for the 3.3V, 5V, and Adjustable version and V
IN
=24V for the 12V version, I
LOAD
=500mA.)
PARAMETER
SYMBOL
TEST CONDITIONS
4.75V≦V
IN
≦40V,
0.2A≦I
LOAD
≦3A
3.3V
Output Voltage
V
OUT
7V≦V
IN
≦40V,
0.2A≦I
LOAD
≦3A
5.0V
15V≦V
IN
≦40V,
0.2A≦I
LOAD
≦3A
12V
3.3V
Efficiency
V
IN
=12V, I
LOAD
=3A
η
5.0V
V
IN
=12V, I
LOAD
=3A
12V
V
IN
=25V, I
LOAD
=3A
UTC P3596-ADJ
4.5V≦V
IN
≦40V,
0.2A≦I
LOAD
≦3A
Feedback Voltage
V
FB
V
OUT
programmed for 3V
η
Efficiency
V
IN
=12V, V
OUT
=3V, I
LOAD
=3A
ALL OUTPUT VOLTAGE
Feedback Bias Current
I
b
Adjustable Version Only, V
FB
=1.3V
Oscillator Frequency
f
o
(Note 1)
Saturation Voltage
V
SAT
I
OUT
=3A (Note 2, 3)
(Note 3)
Max Duty Cycle (ON)
DC
(Note 4)
Min Duty Cycle (OFF)
Current Limit
I
CL
Peak Current (Notes 2, 3)
Output=0V (Notes 2, 4)
Output Leakage Current
I
L
Output=-1V (Note 5)
Quiescent Current
I
Q
(Note 4)
Standby Quiescent Current
I
STBY
ON/OFF pin=5V (OFF) (Note 5)
ON/OFF CONTROL
ON/OFF Pin Logic Input
V
IH
Low (Regulator ON)
Threshold Voltage
V
IL
High (Regulator OFF)
ON/OFF Pin Input Current
I
H
V
LOGIC
=2.5V (Regulator OFF)
V
LOGIC
=0.5V (Regulator ON)
I
L
1.193
1.267
127
3.6
2.0
V
μA
μA
THERMAL DATA
PARAMETER
Thermal Resistance Junction to Case
TO-220B
TO-220-5
TO-263-5
TO-252-5
TO-220B
TO-220-5
TO-263-5
TO-252-5
SYMBOL
θ
Jc
RATINGS
3
3
4
8
45
45
55
90
UNIT
℃/W
Thermal Resistance Junction to Ambient
θ
JA
℃/W
Note 1:
The switching frequency is reduced when the second stage current limit is activated.
Note 2:
No diode, inductor or capacitor connected to output pin.
Note 3:
Feedback pin removed from output and connected to 0V to force the output transistor switch ON.
Note 4:
Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for
the 12V version, to force the output transistor switch OFF.
Note 5:
V
IN
= 40V
UTC
UNISONIC TECHNOLOGIES CO., LTD.
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UTC P3596
Normalized Output Voltage
5.15
5.10
OUTPUT VOLTAGE (V)
LINEAR INTEGRATED CIRCUIT
Line Regulation
5.15
V
IN
=20V, I
LOAD
=3A
Normalized at T
J
=25℃
OUTPUT VOLTAGE (V)
5.10
5.05
5.00
4.95
4.90
4.85
Vout=5V, I
LOAD
=100mA
Normalized at T
J
=25℃
5.05
5.00
4.95
4.90
4.85
-50
-25
0
25
50
75
100
125
0
5
10
15
20
25
30
35
40
JUNCTION TEMPERATURE (℃)
INPUT VOLTAGE (V)
Efficiency
90
3A Load
1.60
Switch Saturation Voltage
1 : -40
℃
2 : 25
℃
3 : 125℃
SATURATION VOLTAGE (V)
85
EFFICIENCY (%)
5.0V
80
75
3.3V
70
65
60
0
5
10
15
20
25
30
35
40
INPUT VOLTAGE (V)
1.40
1.20
1.00
0.80
0.60
0
1
2
3
0.5
1
2
3
SWITCH CURRENT(A)
Switch Current Limit
5.00
30.0
V
IN
=12V, V
OUT
=5V
25.0
20.0
Operating Quiescent Current
4.5V< V
IN
< 4.0V
I
SWITCH
=0
SWITCH CURRENT LIMIT (A)
4.50
4.25
4.00
3.75
3.50
-50
-25
0
25
50
75
100
125
SUPPLY CURRENT (mA)
4.75
Switch ON
15.0
10.0
Switch OFF
5.00
0.00
-50
-25
0
25
50
75
100
125
JUNCTION TEMPERATURE (℃)
JUNCTION TEMPERATURE (℃)
UTC
UNISONIC TECHNOLOGIES CO., LTD.
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