TECHNICAL SPECIFICATIONS
(TA=25°C, airflow rate=600 LFM, Vin=48Vdc, nominal Vout unless otherwise noted.)

H48SN28012_01172008

2

PARA MET ER NOTES and CONDITIONS H48SN28012 (Standard)

Min. Typ. Max. Units
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Continuous 80 Vdc
Transient (100ms) 100ms 100 Vdc
Operating Temperature Please refer to Fig.21 for measuring point -40 110 °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 35 Vdc
Turn-Off Voltage Threshold 31 33 Vdc
Lockout Hysteresis Voltage 1 3 Vdc
Maximum Input Current 100% Load, 36Vin 12.6 A
Minimum -Load Input Current 260 mA
Off Converter Input Current Per ETSI EN300 132-2 15 mA
Inrush Current(I2t) 0.2 1 A2s
Input Reflected-Ripple Current P-P thru 12µH inductor, 5Hz to 20MHz 12 mA
Input Voltage Ripple Rejection 120 Hz 60 dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point Vin=48V, Io=Io.max, Tc=25°C 27.72 28.00 28.28 Vdc
Output Voltage Regulation
Over Load Io=Io,min to Io,max ±20 ±112 mV
Over Line Vin=36V to 75V ±20 ±56 mV
Over Temperature Tc=-40°C to 100°C ±250 ±300 mV
Total Output Voltage Range over sample 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 60 150 mV
RMS Full Load, 1µF ceramic, 10µF Low ESR cap 14 40 mV
Operating Output Current Range 0.3 12.5 A
Output DC Current-Limit Inception Output Voltage 10% Low 120 %
DYNAMIC CHARACTERISTICS
Output Voltage Current Transient 48V, Tested with a aluminum ,10µF Low ESR cap
and 1
µ
F Ceramic load ca
p
,ΔIo/Δt=1A/10
µ
S
Positive Step Change in Output Current 50% Io.max to 75% Io.max 150 mV
Negative Step Change in Output Current 75% Io.max to 50% Io.max 150 mV
Settling Time (within 1% Vout nominal) 300 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 Full load; 5% overshoot of Vout at startup 330 5000 µF
EFFICIENCY
100% Load 91.0 %
60% Load 91.5 %
ISOLATION CHARACTERI STICS
Input to Output 2250 Vdc
Input to Case 2250 Vdc
Output to Case 500 Vdc
Isolation Resistance 10 MΩ
Isolation Capacitance 1900 pF
FEATURE CHARACTERISTICS
Switching Frequency 330 kHz
O
N
/O
FF
Co
ntr
o
l N
ega
tiv
e
R
e
m
o
t
e
O
n
/O
ff l
og
i
c
Logic Low (Module On) Von/off at Ion/off=1.0mA 0 0.8 V
Logic High (Module Off) Von/off at Ion/off=0.0 µA 15 V
ON/OFF Control, Positive Remote On/Off logic
Logic Low (Module Off) Von/off at Ion/off=1.0mA 0 0.8 V
Logic High (Module On) Von/off at Ion/off=0.0 µA 15 V
ON/OFF Current Ion/off at Von/off=0.0V 1 mA
Leakage Current Logic High, Von/off=15V 50 uA
Output Voltage Trim Range Across Pins 9 & 5, Pout ≦ max rated power -40 +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 1.35 M hours
Weight 62 grams
Over-Temperature Shutdown Please refer to Fig.21 for measuring point 115 °C