
For technical support and more information, see inside back cover or visit www.ti.com/powertrends
PT78NR100 Series
Standard Application
C1 = Required 100F electrolytic (1)
C2 = Required 100F electrolytic (1)
Ordering Information
PT78NR1
Pin-Out Information
Pin
Function
1+Vin
2-Vout
3
GND
Negative output from positive input
Wide Input Range
Self-Contained Inductor
Short Circuit Protection
Over-Temperature Protection
Fast Transient Response
The PT78NR100 Series creates a
negative output voltage from a posi-
tive input voltage greater than 7V.
These easy-to-use, 3-terminal, Inte-
grated Switching Regulators (ISRs)
have maximum output power of 5
watts and a negative output voltage
that is laser trimmed. They also have
excellent line and load regulation.
1 Amp Plus to Minus Voltage
Integrated Switching Regulator
PT78NR100
+
-Vout
COM
Vin
1
3
2
C2
C1
+
XX
Y
Pkg Style 500
SLTS058B
(Revised 8/31/2000)
Output Voltage
03
= -3.0 Volts
05
= -5.0 Volts
52
= -5.2 Volts
06
= -6.0 Volts
07
= -7.0 Volts
08
= -8.0 Volts
09
= -9.0 Volts
10
= -10.0 Volts
12
= -12.0 Volts
14
= -13.9 Volts
15
= -15.0 Volts
Package Suffix
V
= Vertical Mount
S
= Surface Mount
H
= Horizontal
Mount
Specifications
Characteristics
PT78NR100 SERIES
(T
a= 25°C unless noted)
Symbols
Conditions
Min
Typ
Max
Units
Output Current
Io
Over Vin range
Vo=-5V
0.05 (2)
—
1.00
Vo=-6V
0.05 (2)
—0.8
Vo=-7, -8, -9V
0.05 (2)
—
0.55
A
Vo=-10V
0.05 (2)
—0.5
Vo=-12V
0.05 (2)
—
0.40
Vo=-13.9, -15V
0.05 (2)
—
0.30
Short Circuit Current
Isc
Vin=10V
—
4
×Imax
—
Apk
Inrush Current
Iir
Vin=10V
—
4
—
A
tir
On start-up
—
0.5
—
mSec
Input Voltage Range
Vin
0.1
≤ Io ≤ Imax
Vo=-5V
7
—
25
V
Vo=-6, -7, -8, -9V
7
—
21
V
Vo=-10, -12V
7
—
18
V
Vo=-13.9, -15V
7
—
15
V
Output Voltage Tolerance
Vo
Over Vin range
—
±1.0
±3.0
%Vo
Ta=-20°C to +70°C
Line Regulation
Regline
Over Vin range
—
±0.5
±1.0
%Vo
Load Regulation
Regload
0.1
≤ Io ≤ Imax
—
±0.5
±1.0
%Vo
Vo Ripple/Noise
Vn
Vin=10V, Io=Imax
—±2
—%Vo
Transient Response
ttr
50% load change
—
100
250
Sec
(with 100F output cap)
Vo over/undershoot
—
5.0
—
%Vo
Efficiency
η
Vin=10V, Io=0.5×Imax, Vo = -5V
—
75
—
%
Switching Frequency
o
Over Vin and Io ranges
600
650
700
kHz
Absolute Maximum
Ta
Free Air Convection, (40-60LFM)
-40
—
+85 (3)
°C
Operating Temperaturte Range
Over Vin Range
Thermal Resistance
θ
ja
Free Air Convection, (40-60LFM)
—
45
—
°C/W
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,
—5
—
G’s
20-2000 Hz, soldered in a PC board
Weight
—
6.5
Grams
Notes:
(1) The PT78NR100 Series requires a 100F electrolytic or tantalum capacitor at both the input and output for proper operation in all applications. The input
capacitor, C1 must have a ripple current rating ≥600 mArms, and an ESR ≤0.2.
(2) The ISR will operate down to no load with reduced specifications.
(3) See Thermal Derating chart.