TI PT79SR105

For assistance or to order, call
Application Notes
Mechanical Outline
Product Selector Guide
(800) 531-5782
PT79SR100 S e r i e s
-1.5 AMP NEGATIVE STEP-DOWN
INTEGRATED SWITCHING REGULATOR
•
•
•
•
Standard Application
COM
High Efficiency > 85%
Self-Contained Inductor
Short Circuit Protection
Over-Temperature Protection
The PT79SR100 Series is a new
line of Negative Input/Negative Output 3-terminal Integrated Switching
Regulators (ISRs). These ISRs have a
maximum output current of -1.5 Amps
and an output voltage that is laser
trimmed to most industry standard voltages. They have excellent line and load
regulation, and are ideal for applications,
such as RS232 and Ethernet communications, ECL logic, and op-amp circuitry.
Pin-Out Information
Ordering Information
PT79SR1
D1
1
-Vin
2
PT79SR1
Function
1
GND
2
-Vin
Output Voltage
Package Suffix
3
-Vout
05 = -5.0 Volts
52 = -5.2 Volts
08 = -8.0 Volts
09 = -9.0 Volts
12 = -12.0 Volts
15 = -15.0 Volts
V = Vertical Mount
S = Surface Mount
H = Horizontal
Mount
C2
-Vout
3
Y
XX
Pin
COM
C1
Revised 5/15/98
C1 = Optional ceramic (1µF)
C2 = Optional ceramic (1-5µF)
D1 = Zener diode required to clamp
turn-on overshoot
(See Application Note)
Pkg Style 500
Specifications
PT79SR100 SERIES
Characteristics
(Ta = 25°C unless noted)
Symbols
Conditions
Min
Typ
Max
Units
Output Current
Io
Over Vin range
-0.1*
—
-1.5
A
Short Circuit Current
Isc
Vin=Vo-4V
—
-3.5
—
Apk
Input Voltage Range
Vin
Io=-0.1 to -1.5 A
-0.1 ≥ Io ≥ -1.5 A
-9
-19
—
—
-30
-30
V
V
Output Voltage Tolerance
∆Vo
Over Vin range, Io=-1.5 A
Ta=-20°C to shutdown
—
±1.0
±3.0
%Vo
Line Regulation
Regline
Over Vin range
—
±1.0
±2.0
%Vo
Load Regulation
Regload
-0.1 ≤ Io ≤ -1.5 A
—
±0.5
±1.0
%Vo
Vo Ripple/Noise
Vn
Vin=-15V, Io=-1.0 A,Vo=-5V
—
35
—
mVpp
Transient Response
ttr
50% load change
Vo=overshoot/undershoot
—
—
100
30
—
—
µSec
%Vo
Efficiency
η
Vin=-10V, Io=-1.0A, Vo=-5V
—
85
—
%
Switching Frequency
ƒo
Over Vin and Io ranges
0.95
1.0
1.05
MHz
Absolute Maximum
Operating Temperature Range
Ta
-40
—
+85
°C
Recommended Operating
Temperature Range
Ta
Free Air Convection, (40-60LFM)
Over Vin and Io ranges
-40
—
+60**
°C
Thermal Resistance
θja
Free Air Convection, (40-60LFM)
—
45
—
°C/W
Temperature Coefficient
Tc
Over Vin and Io ranges
—
±0.5
±1.5
mV/°C
Storage Temperature
Ts
—
-40
—
+125
°C
Mechanical Shock
—
Per Mil-STD-883D, Method 2002.3
—
500
—
G’s
Mechanical Vibration
—
Per Mil-STD-883D, Method 2007.2,
20-2000 Hz, soldered in a PC board
—
5
—
G’s
Weight
—
—
—
7.0
—
Grams
* ISR will operate down to no load with reduced specifications.
22
Vo=-5V
Vo=-15V
** See Thermal Derating chart.
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
(800) 531-5782
For assistance or to order, call
PT79SR100 S e r i e s
CHARACTERISTIC
Efficiency vs Output Current
Efficiency vs Output Current
100
Efficiency vs Output Current
Vin
9V
10.0V
15.0V
20.0V
25.0V
30.0V
80
70
60
90
Vin
16.0V
80
20.0V
70
25.0V
60
Efficiency - %
90
50
0.5
0.75
1
1.25
0
0.25
0.5
Iout-(Amps)
1
1.25
1.25
80
Vin
30.0V
60
25.0V
20.0V
0.5
0.75
1
1.25
0.6
19.0V
50˚C
0.75
0
0
70˚C
85˚C
50˚C
1.2
70˚C
1
0.8
0.6
85˚C
0
17
19
21
23
25
27
29
31
18
20
22
Power Dissipation vs Output Current
0.5
2
1.5
25.0V
20.0V
1
16.0V
1.5
Vin
2
30.0V
27.0V
24.0V
21.0V
19.0V
1.5
1
0
0
1.25
30
0.5
0.5
0
28
2.5
Vin
30.0V
PD-(Watts)
PD-(Watts)
1
26
Power Dissipation vs Output Current
2.5
30.0V
25.0V
20.0V
15.0V
10.0V
9V
24
Vin-(Volts)
Vin
1.5
(See Note 2)
60˚C
Vin-(Volts)
2
1.5
0.2
Vin-(Volts)
Power Dissipation vs Output Current
1.25
0.4
15
9 11 13 15 17 19 21 23 25 27 29 31
1
1.4
0.6
0.2
Iout-(Amps)
0.5
1.6
60˚C
0.8
0.2
1
0.25
Thermal Derating (Ta)
(See Note 2)
1
0.4
0.75
21.0V
0
1.2
0.4
0.5
24.0V
60
Iout-(Amps)
Iout-(Amps)
0.8
0.25
27.0V
Iout-(Amps)
1.4
70˚C
0
30.0V
90
1.5
1.6
85˚C
7
Vin
0
0.25
Thermal Derating (Ta)
50˚C
60˚C
1
1.5
30
0
1.5
(See Note 2)
1.4
1.25
120
Iout-(Amps)
1.6
1
150
Iout-(Amps)
1.2
0.75
Ripple vs Output Current
0
Thermal Derating (Ta)
0.5
16.0V
0
1
0.25
Iout-(Amps)
40
10
PD-(Watts)
0
20
0.75
30.0V
1.5
Ripple-(mV)
30
Ripple-(mV)
Ripple-(mV)
Vin
30.0V
25.0V
20.0V
15.0V
10.0V
9V
40
20
Iout-(Amps)
0.75
100
50
0.5
27.0V
Ripple vs Output Current
60
0.25
24.0V
Iout-(Amps)
Ripple vs Output Current
0
21.0V
70
40
40
1.5
19.0V
80
50
40
0.25
Vin
90
60
30.0V
50
0
(See Note 1)
100
100
Efficiency - %
Efficiency - %
PT79SR115, -15.0 VDC
(See Note 1)
0
0.25
0.5
0.75
1
1.25
1.5
0
0.25
0.5
Iout-(Amps)
0.75
1
1.25
1.5
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 soldered in a printed circuit board. (See Thermal Application Notes.)
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
23
DATA SHEETS
PT79SR112, -12.0 VDC
(See Note 1)
Wide Input Range Products
PT79SR105, -5.0 VDC
DATA
IMPORTANT NOTICE
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue
any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF
DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL
APPLICATIONS”). TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR
WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER
CRITICAL APPLICATIONS. INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO
BE FULLY AT THE CUSTOMER’S RISK.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other
intellectual property right of TI covering or relating to any combination, machine, or process in which such
semiconductor products or services might be or are used. TI’s publication of information regarding any third
party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.
Copyright  1999, Texas Instruments Incorporated