UC3903N UNITRODE, UC3903N Datasheet - Page 5

• Manufacturer Part Number: UC3903N
• Description: IC, SUPPLY/LINE MONITOR 18mA, 40V 18-DIP
• Manufacturer: UNITRODE

Specifications of UC3903N

• Threshold Voltage: 2.5V
• No. Of Supervisors / Monitors: 4
• Supply Voltage Range: 8V To 40V
• Reset Type: Active-Low
• Supply Current: 18mA
• Delay Time: 30ms
• Digital Ic Case Style: DIP
• No. Of Pins: 18
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Copyright © 1999–2008, Texas Instruments Incorporated
V
ADJ
OUTPUT
- 0.1
- 0.2
- 0.3
- 0.4
- 0.5
- 0.6
- 0.7
A.
0.2
0.1
2.5 V
R
R
0
- 55 - 35 - 15
S
A
The UC1903 fault window circuitry generates OV and UV thresholds centered around the 2.5-V reference. Window
magnitude and threshold hysteresis are proportional to the window adjust input voltage at Pin 4.
........................................................................................................................................
2.5 kW
2.5 kW
UC1903
15 W
T - Junction Temperature - °C
+VIN
CANCELLATION
Temperature Characteristic
J
AND MIRROR
Q1
Typical 2.5 V Reference
R1
R3
CIRCUITS
R2
5
BIAS
Q2
25
REFERENCE
vs
CIRCUIT
Q3
Figure 1. Operation and Application Information
45
I
O
Product Folder Link(s):
65
=
R4
8 kW
V
R4
ADJ
85
Typical Characteristics
105
1.25 V
Block Diagram
125
UC1903 UC2903 UC3903
I
I
OA
OC
R5
R7
R8
R6
40
35
30
20
25
- 55 - 35 - 15
1.84 kW
0.16 kW
0.16 kW
1.84 kW
Temperature Characteristic (C
SLUS233A – OCTOBER 1999 – REVISED SEPTEMBER 2008
I
OB
T - Junction Temperature - °C
J
I
OD
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Typical Fault Delay
5
25
Q4
Q5
THREAHOLD and HYSTERESIS
vs
45
FAULT WINDOW
DELAY
65
CIRCUITS
TO
OV HYSTERESIS
CONTROL
OV THRESHOLD
UV THRESHOLD
TO
UV HYSTERESIS
CONTROL
85
≥
270 pF)
105
UC1903
UC2903
UC3903
125
5