Datasheet

DS_DIM3R3400_08142013 E-mail: [e-mail]
http://www.deltaww.com/dcdc
P10
FEATURES AND DESIGN
CONSIDERATIONS (CONTINUED)
The PICMG 3.0’s requirements for the 0 Vdc transient is
going to remain 5mS the fall slew rate is 50V/ms and
rise slew rate 12.5 V/ms. This requirement will lead to a
8.7ms T_HLDP requirement assuming power is
interrupted at -35Vdc (Vth).
Considering Power is 435.85W(The downstream
DC/DC converter input power is 400W/95%=421W;the
3.3V power is 3.3V*3.6A/80%=14.85W,So total power is
435.85W), Vth is 35V, Vcap=90V,
)(1103
3590
7.8*85.435*2
_
22
uFHLDPC 


When the input voltage is at the threshold of discharge,
C_HLDP will go off line and the charge pump will
recharge it .
External Hold Up Trim Resistor
Rtrim is the external hold-up trim resistance for a given
desired nominal hold-up capacitor charge voltage
(Vcap), the detailed equation is
)(10000
50
500000



Vhu
R
trim
Over-Current Protection
DIM3R3400 provides over current protection levels to
protect downstream DC/DC converter over power rating.
When the downstream DC/DC converter over power
rating and caused our output current exceeds the current
limit level, the module will shut down immediately. After a
fixed delay time, the module will try to restart. Then it will
go through the restarting procedure.
A/B Feed / Fuse Alarm (-48V_ALARM)
The input feeds A and B are monitored. The module will
send an opto-isolated signal if any of the feed is below
the voltage threshold (typical 38.4V). Therefore, the
loss of any A or B feed can be detected. The opto
coupler transistor on state indicates a normal status
and off state indicates a fault condition.
Input Under Voltage Lockout
The input under-voltage lockout prevents the module from
being damaged by low input voltage. When the input
voltage is lower than its threshold voltage, the module will
be turned off. The lockout occurs between -26V to -28V.
Transient Over Voltage Protection
The PICMG 3.0 requires the module work normally
under 100V/10μS input voltage transient. DIM3R3400
can meet the requirement. An internal TVS with
80V/1500W peak pulse power rating will suppress the
100V transient voltage. For the 100V pulse voltage, the
power train impedance will damp it below internal
components rating without shut down the module.
Management Power(3.3V) and
Blue_LED Power(5.0V)
The module contains two isolated DC output. The first
output provides up to 3.3V/3.6A management power
(reference to LOGIC_GND). This power is used to
power the IPM controller for the ATCA board or to power
up system controller for other applications. The second
isolated output, 5V/150mA, is used to power the Blue
LED per PICMG 3.0 requirement.
The management power is available as soon as the
input voltage levels are within –36Vdc to –75Vdc. short
circuit and over voltage protected are built in it. The
module will going into hiccup mode when OCP or short
happened. The output voltage will keep a constant
when over voltage happened, and the value is the ovp
point. No additional output capacitors are required, but a
22µF tantalum/ceramic and a 0.01µF to 0.1µF ceramic
capacitors are highly recommended to reduce the
switching ripple and noise. Higher output capacitance
may be required in case of large input line or output load
transient conditions.