PT78NR100 Series
1 Amp Plus to Minus Voltage
Integrated Switching Regulator
SLTS058B
(Revised 8/31/2000)
• 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.
Pin-Out Information
Ordering Information
Pin Function
PT 78NR1
XX Y
1
2
3
+V
in
Standard Application
-Vout
Output Voltage
Package Suffix
GND
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
V = Vertical Mount
S = Surface Mount
H = Horizontal
Mount
Vin
-Vout
COM
1
2
PT78NR100
3
+
C2
C1
COM
+
C1 = Required 100µF electrolytic (1)
C2 = Required 100µF electrolytic (1)
Pkg Style 500
Specifications
PT78NR100 SERIES
Typ Max
Characteristics
(T = 25°C unless noted)
a
Symbols
Conditions
Min
Units
Output Current
Io
Over Vin range Vo=-5V
Vo=-6V
0.05 (2)
—
—
—
—
—
—
1.00
0.8
(2)
0.05
(2)
Vo=-7, -8, -9V
0.05
0.55
0.5
A
Vo=-10V
0.05 (2)
(2)
Vo=-12V
0.05
0.40
0.30
(2)
Vo=-13.9, -15V
0.05
Short Circuit Current
Inrush Current
Isc
Vin=10V
—
4×Imax
—
Apk
Iir
tir
Vin=10V
—
—
4
—
—
A
On start-up
0.5
mSec
Input Voltage Range
Vin
0.1 ≤ Io ≤ Imax
Vo=-5V
7
7
7
7
—
—
—
—
25
21
18
15
V
V
V
V
Vo=-6, -7, -8, -9V
Vo=-10, -12V
Vo=-13.9, -15V
Output Voltage Tolerance
∆Vo
Over Vin range
—
±1.0
±3.0
%Vo
Ta=-20°C to +70°C
Over Vin range
0.1 ≤ Io ≤ Imax
Line Regulation
Load Regulation
Vo Ripple/Noise
Regline
Regload
Vn
—
—
—
±0.5
±0.5
±2
±1.0
±1.0
—
%Vo
%Vo
%Vo
Vin=10V, Io=Imax
Transient Response
(with 100µF output cap)
ttr
50% load change
Vo over/undershoot
—
—
100
5.0
250
—
µSec
%Vo
Efficiency
η
Vin=10V, Io=0.5×Imax, Vo = -5V
—
75
—
%
Switching Frequency
ƒo
Ta
Over Vin and Io ranges
600
650
700
kHz
Absolute Maximum
Operating Temperaturte Range
Free Air Convection, (40-60LFM)
Over Vin Range
-40
—
+85 (3)
°C
Thermal Resistance
Storage Temperature
Mechanical Shock
θja
Ts
—
—
Free Air Convection, (40-60LFM)
—
—
45
—
°C/W
°C
-40
—
—
+125
—
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
—
—
6.5
Grams
Notes: (1) The PT78NR100 Series requires a 100µF 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 ≤0.2Ω.
(2) The ISR will operate down to no load with reduced specifications.
(3) See Thermal Derating chart.
For technical support and more information, see inside back cover or visit www.ti.com/powertrends