
For assistance or to order, call (800) 531-5782
PT5100 Series
1 AMP POSITIVE STEP-DOWN
INTEGRATED SWITCHING REGULATOR
Application Notes
Mechanical Outline
Product Selector Guide
Revised 5/15/98
• 85% Efficiency
• Internal Short-Circuit Protection
• Pin-Compatible with 3-Terminal
Linear Regulators
• Laser-Trimmed Output Voltage
• Over-Temperature Protection
• Small Footprint
• Wide Input Range
use, 1 Amp positive step-down, 3-terminal Integrated Switching Regulators
(ISRs) designed for pin compatibility
with linear regulators. These ISRs can
be used in a wide variety of on-board
power regulation applications including
computer, data storage, industrial controls, medical, and battery powered
equipment. The series of ISRs has ex-
Standard Application
Vin
1
PT5100
C1
C1 = Optional 1µF ceramic
C2 = Required 100µF electrolytic
2
The PT5100 Series is Power
Trends’ line of economical, easy-to-
Pin-Out Information
Pin Function
1
2
3
Vout
3
+
C2
COMCOM
V
in
GND
V
out
Pkg Style 100
Ordering Information
PT5101¨ = + 5 Volts
PT5102¨ = + 12 Volts
PT5103¨ = + 3.3 Volts
PT5105¨ = + 6.5 Volts
PT5107¨ = + 15 Volts
PT5109¨ = + 5.6 Volts
PT5110¨ = + 9 Volts
PT5111¨ = + 10 Volts
PT5112¨ = + 8 Volts
cellent line and load regulation and
laser-trimmed output voltage.
PT Series Suffix
Case/Pin
Configuration
Vertical Through-Hole N
Horizontal Through-Hole A
Horizontal Surface Mount C
(PT1234X)
Specifications
Characteristics
(Ta =25°C unless noted) Symbols Conditions Min Typ Max Units
Output Current I
Short Circuit Current I
Input Voltage Range V
Output Voltage Tolerance ∆V
Line Regulation Reg
Load Regulation Reg
Vo Ripple/Noise V
Transient Response t
with Co = 100µF V
Efficiency η Vin=9V, Io=0.5A, Vo=3.3V — 82 — %
Switching Frequency ƒ
Absolute Maximum T
Operating Temperature Range
Recommended Operating T
Temperature Range (40-60LFM) V
Thermal Resistance
Storage Temperature T
Mechanical Shock Per Mil-STD-883D, Method 2002.3
Mechanical Vibration Per Mil-STD-883D, Method 2007.2
Weight — 4.5 — grams
* ISR will operate down to no load with reduced specifications.
**See Thermal Derating chart.
Note:
The PT5100 Series requires a 100µF electrolytic or tantalum output capacitor for proper operation in all applications.
o
sc
in
o
line
load
n
tr
os
o
a
a
θ
ja
s
Over Vin range 0.1* — 1.0 A
min — 3.5 — Apk
Vin = V
in
0.1 ≤ Io ≤ 1.0 A V
V
V
V
Over Vin Range, Io = 1.0 A
T
= 0°C to +60°C
a
Over Vin range — ±0.5 ±1.0 %V
0.1 ≤ Io ≤ 1.0 A — ±0.5 ±1.0 %V
Vin=V
25% load change — 100 200 µSec
Vo over/undershoot — 5.0 — %V
=9V, Io=0.5A, Vo=5V — 85 — %
V
in
=16V, Io=0.5A, Vo=12V — 90 — %
V
in
Vin=19V, Io=0.5A, Vo=15V — 92 — %
Over Vin and Io ranges, Vo= 3.3V 575 725 875
Free Air Convection, Vo= 3.3V -20 — +80**
At Vin= 24V, Io=0.75A Vo= 12V -20 — +80**
Free Air Convection V
(40-60LFM) V
1 msec, Half Sine, mounted to a fixture
20-2000 Hz, Soldered in a PC board
=1.0 A — ±2 — %V
min, I
in
o
= 3.3V 9 — 26 V
o
= 5V 9 38 V
o
= 12V 16 38 V
o
= 15V 19 38 V
o
= >5V 500 650 800
V
o
= 5V -20 — +80** °C
o
= 3.3V — 45 —
o
= 5V — 50 — °C/W
o
V
= 12V/15V — 60 —
o
PT5100 SERIES
— ±1.5 ±3.0 %V
-20 — +85 °C
-40 — +125 °C
— 500 — G’s
—5 —G’s
o
o
o
o
o
kHz
4
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com

For assistance or to order, call (800) 531-5782
PT5100
Series
CHARACTERISTIC DATA
PT5103, 3.3 VDC (See Note 1) PT5101, 5.0 VDC (See Note 1) PT5102, 12.0 VDC (See Note 1)
Efficiency vs Output Current Efficiency vs Output Current
100
90
80
70
Efficiency - %Ripple-(mV)Iout-(Amps)PD-(Watts)
60
50
40
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Vin
9.0V
12.0V
18.0V
24.0V
26.0V
90
85
80
75
70
65
60
Efficiency - %
55
50
45
40
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Ripple vs Output Current Ripple vs Output Current
60
50
40
30
20
10
0
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Vin
26.0V
24.0V
18.0V
12.0V
9.0V
120
100
80
60
40
Ripple-(mV)
20
0
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Vin
9.0V
12.0V
18.0V
24.0V
30.0V
38.0V
Vin
38.0V
30.0V
24.0V
18.0V
12.0V
9.0V
Efficiency vs Output Current
100
90
80
70
Efficiency - %
60
50
40
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Ripple vs Output Current
250
200
150
100
Ripple-(mV)Iout-(Amps)
50
0
0 0.2 0.4 0.6 0.8 1
Iout-(Amps)
Wide Input Range Products
DATA SHEETS
Vin
16.0V
20.0V
24.0V
30.0V
35.0V
38.0V
Vin
38.0V
35.0V
30.0V
24.0V
20.0V
16.0V
Thermal Derating (Ta) (See Note 2) Thermal Derating (Ta) (See Note 2)
1
0.8
0.6
0.4
0.2
0
7 9 11 13 15 17 19 21 23 25 27
85°C
70°C
1
0.8
0.6
0.4
Iout-(Amps)
0.2
0
7 1115192327313539
70°C
85°C
50°C
60°C
Thermal Derating (Ta) (See Note 2)
1
0.8
0.6
0.4
0.2
0
15 17 19 21 23 25 27 29 31 33 35 37 39
Vin-(Volts) Vin-(Volts)Vin-(Volts)
Power Dissipation vs Output Current Power Dissipation vs Output Current
1.2
1
0.8
0.6
0.4
0.2
0
0 0.2 0.4 0.6 0.8 1
Vin
26.0V
24.0V
18.0V
12.0V
9.0V
1.8
1.6
1.4
1.2
1
0.8
PD-(Watts)
0.6
0.4
0.2
0
0 0.2 0.4 0.6 0.8 1
Vin
38.0V
30.0V
24.0V
18.0V
12.0V
9.0V
Power Dissipation vs Output Current
2.4
2
1.6
1.2
PD-(Watts)
0.8
0.4
0
0 0.2 0.4 0.6 0.8 1
Iout-(Amps) Iout-(Amps) Iout-(Amps)
Note 1: All data listed in the above graphs, except for derating data, has been developed from actual products tested at 25°C. This data is considered typical data for the ISR.
Note 2: Thermal derating graphs are developed in free air convection cooling of 40-60 LFM. (See Thermal Application Notes.)
85°C
70°C
60°C
50°C
Vin
38.0V
35.0V
30.0V
24.0V
20.0V
16.0V
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
5

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