TECHNICAL SPECIFICATIONS
(T
A
=25°C, V
in
=48Vdc, nominal Vout unless otherwise noted.)
DS_F48SA28025_12072007
2
PARAMETER
NOTES and CONDITIONS
F48SA28025 (Standard)
Min. Typ.
Max. Units
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Continuous
80
Vdc
Transient (100ms)
100ms
100
Vdc
Operating Temperature
Please refer to Fig 20 for measuring point
-40
95
°C
Storage Temperature
-55
125
°C
Input/Output Isolation Voltage
2250
Vdc
INPUT CHARACTERISTICS
Operating Input Voltage
36
48
75
Vdc
Input Under-Voltage Lockout
Turn-On Voltage Threshold
33
34.5
36
Vdc
Turn-Off Voltage Threshold
31
32.5
34
Vdc
Lockout Hysteresis Voltage
2
Vdc
Input Over-Voltage Lockout
Turn-On Voltage Threshold
76
78
80
Vdc
Turn-Off Voltage Threshold
78
80
82
Vdc
Lockout Hysteresis Voltage
2
Vdc
Maximum Input Current
100% Load, 36Vin
23
A
Inrush Current(I
2
t)
1
A
2
s
Input Reflected-Ripple Current
P-P thru 15µH inductor, 5Hz to 20MHz
20
mA
Input Voltage Ripple Rejection
120 Hz
50
dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point
Vin=48V, Io=Io.max, Tc=25°C
27.44
28.00
28.56
Vdc
Output Voltage Regulation
Over Load
Io=Io,min to Io,max
28
56
mV
Over Line
Vin=36V to 75V
28
56
mV
Over Temperature
Tc=-40°C to 100°C
100
300
mV
Total Output Voltage Range
over all load, line and temperature
27.25
28.00
28.75
V
Output Voltage Ripple and Noise
5Hz to 20MHz bandwidth
Peak-to-Peak
Full Load, 1µF ceramic, 10µF Low ESR cap
200
mV
RMS
Full Load, 1µF ceramic, 10µF Low ESR cap
65
mV
Operating Output Current Range
2
25
A
Output DC Current-Limit Inception
Output Voltage 10% Low
120
150
%
DYNAMIC CHARACTERISTICS
Output Voltage Current Transient
48V, Tested with a 10µF, a 1µF Ceramic cap and a
470uF low ESR aluminum load cap,
Δ
Io/
Δ
t=1A/µs
Positive Step Change in Output Current
50% Io.max to 75% Io.max
450
mV
Negative Step Change in Output Current
75% Io.max to 50% Io.max
450
mV
Settling Time (within 1% Vout nominal)
500
us
Turn-On Transient
Start-Up Time, From On/Off Control
20
35
ms
Start-Up Time, From Input
20
35
ms
Output Capacitive Load
470
6000
µF
EFFICIENCY
100% Load
91.5
%
60% Load
91.5
%
ISOLATION CHARACTERISTICS
Input to Output
2250
Vdc
Input to Case
1500
Vdc
Output to Case
1500
Vdc
Isolation Resistance
10
M
Ω
Isolation Capacitance
1800
pF
FEATURE CHARACTERISTICS
Switching Frequency
300
kHz
Output overshoot Voltage during start up
0
Power good pin max applied voltage
Max sink current 5mA
35
V
Auxiliary output voltage
Aux pin source current <=20mA
Referenced to Sense(-) pin
7
10
13
V
Output Voltage Trim Range
Pout
≦
max rated power
-15
+10
%
Output Voltage Remote Sense Range
Pout
≦
max rated power
0.5
V
Output Over-Voltage Protection
Over full temp range; % of nominal Vout
115
140
%
GENERAL SPECIFICATIONS
MTBF
Io=80% of Io, max; Ta=25°C
1.14
M hours
Weight
168
grams
Over-Temperature Shutdown
Please refer to Fig.20 for measuring point
100
°C