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Cassette Style
100 Watt DC-DC Converters
S Series
Edition 1/01.2000
27/31
Table 17: Undervoltage monitor functions
Output type
Monitoring
Minimum adjustment range
Typical hysteresis
Uh [% of Ut]
JFET
NPN
U i
Uo1
of threshold level
U t
for
U t min...U t max
Uti
Uto
Uhi
Uho
D1
D5
no
yes
-
3.5...40 V 1
-
2.5...0.6
D2
D6
yes
no
Ui min...Ui max 1
-
3.4...0.4
-
D3
D7
yes
Ui min...Ui max 1
(0.95...0.985
Uo1) 2
3.4...0.4
"0"
D4
D8
no
yes
-
(0.95...0.985
Uo1) 2
-"0"
D0
D9
no
yes
-
3.5...40 V 3
-
2.5...0.6
yes
no
Ui min...Ui max 3 4
-
3.4...0.4
-
yes
Ui min...Ui max 3 4
3.5...40 V 3
3.4...0.4
2.5...0.6
yes
Ui min...Ui max 3 4
(0.95...0.985
Uo1) 2
3.4...0.4
"0"
-
DD
yes
Ui min...Ui max 1
3.5...40 V 1
3.4...0.4
2.5...0.6
1 Threshold level adjustable by potentiometer
2 Fixed value tracking if Uo1 is adjusted via R-input, option P or sense lines.
3 The threshold level permanently adjusted according to customer specification
±2% at 25°C. Any value within the specified range is
basically possible but causes a special type designation in addition to the standard option designations (D0/D9 respectively)!
4 Adjusted at Io nom
Fig. 30
Option D1...D0: JFET output, ID ≤ 2.5 mA
NPN output (D5...DD):
Connector pin D is internally connected via the collector-
emitter path of a NPN transistor to the negative potential of
output 1.
UD < 0.4 V (logic low) corresponds to a monitored
voltage level (
Ui and/or Uo1) > Ut +Uh. The current ID
through the open collector should not exceed 20 mA. The
NPN output is not protected against external overvoltages.
UD should not exceed 40 V.
Ui, Uo1 status
UD
Ui or Uo1 < Ut
high, H,
ID ≤ 25 A at UD = 40 V
Ui and Uo1 > Ut + Uh
low, L,
UD ≤ 0.4 V at ID = 20 mA
Threshold tolerances and hysteresis:
If
Ui is monitored, the internal input voltage after the input
filter is measured. Consequently this voltage differs from
the voltage at the connector pins by the voltage drop
DUt i
across the input filter. The threshold levels of the D0 and D9
options are factory adjusted at nominal output current
Io nom
and at
TA = 25
°C. The value of DU
t i depends upon the input
voltage range (CS, DS, ..), threshold level
Ut, temperature
and input current. The input current is a function of the input
voltage and the output power.
Fig. 32
Definition of Ut i, DUt i and DUh i (JFET output)
JFET output (D0…D4):
Connector pin D is internally connected via the drain-
source path of a JFET (self-conducting type) to the nega-
tive potential of output 1.
UD ≤ 0.4 V (logic low) corresponds
to a monitored voltage level (
Ui and/or Uo1) < Ut. The cur-
rent
ID through the JFET should not exceed 2.5 mA. The
JFET is protected by a 0.5 W Zener diode of 8.2 V against
external overvoltages.
Ui, Uo1 status
D output,
UD
Ui or Uo1 < Ut
low, L,
UD ≤ 0.4 V at ID = 2.5 mA
Ui and Uo1 > Ut + Uh
high, H,
ID ≤ 25 A at UD = 5.25 V
Vo1+
Vo1–
D
UD
ID
Rp
Input
11007
DUti
Uhi
UD low
UD
UD high
Ui
P
o
=
P
o
nom
P
o
=
0
P
o
=
0
Uti
P
o
=
P
o
nom
11021
Vo1+
Vo1–
D
UD
ID
Rp
Input
11006
Fig. 31
Option D5...DD: NPN output, Uo1
≤ 40 V, I
D
≤ 20 mA