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VB408 / VB408B / VB408FI
HIGH VOLTAGE LINEAR REGULATOR POWER I.C.
PRELIMINARY DATA
TYPE VB408 VB408FI VB408B
∆VIN,OUT
400 V
ILIM 40 mA
V OUT 1.25 to VIN-30 V
2 3
3
INPUT VOLTAGE UP TO 400 V DC OR 285 V RMS RECTIFIED s OUTPUT VOLTAGE ADJUSTABLE FROM 1.25 TO VIN-30V s OUTPUT CURRENT LIMITED TO 40 mA s THERMAL SHUT-DOWN PROTECTION s SHORT CIRCUIT PROTECTION
s
1
TO-220
ISOWATT220
1
2
3 1
DESCRIPTION
The VB408, VB408B, VB408FI are fully protected positive adjustable voltage regulators made using a proprietary High Voltage VIPower™ technology. The device can be connected to a D.C. source (up to 400V) or in off-line application directly to the rectified main (110V/ 230V). It is particularly suitable to be used in the manufacture of DC/DC converters, AC/DC converters,
D2PAK ORDER CODES : VB408 TO-220 ISOWATT220 VB408FI D2PAK VB408B
start-up circuits, pneumatic valve drivers and current sources. The device is able to drive resistive or inductive loads with an output voltage from 1.25V to VIN-30V providing an internally limited output current; it has built in short circuit and thermal shutdown protections. The device does not provide galvanic insulation from main.
BLOCK DIAGRAM
V IN
Power Stage
BIAS CIRCUIT
CURRENT SENSE
V OUT
Current Limitation
+ _
Thermal
RE F 3 REF 2
+
_
Protection
C ontrol Signal
+ _
RE F 1
AD J
FC00410
September 1999
1/8
1
VB408 / VB408B / VB408FI
ABSOLUTE MAXIMUM RATING Symbol Parameter Input to Output Voltage at 20 mA Output current Electrostatic discharge (R=1.5kΩ, C=100pF) Power dissipation at TC=25oC Junction operating temperature Storage temperature TO-220 Value ISOWATT220 - 0.2 to 420 Internally limited 2000 31 - 40 to150 - 55 to 150 D2PAK Unit V mA V W °C °C
∆VIN,OUT
IOUT VESD Ptot Tj TSTG
89
89
THERMAL DATA Symbol Rthj-case Rthj-amb Parameter Thermal resistance junction-case Thermal resistance junction-ambient (MAX) (MAX) TO-220 1.4 60 Value ISOWATT220 4 60 D2PAK 1.4 35 (*) Unit °C/W °C/W
(*) When mounted using the minimum recommended pad size on FR-4 board (1 inch2 )
CONNECTION DIAGRAM (TOP VIEW)
3 2 1
VOUT VIN ADJ
3 2 1
VOUT VIN ADJ
TO-220 / ISOWATT220
D2PAK
ELECTRICAL CHARACTERISTICS (VIN=300VDC; -25°C 1µF) must be chosen. In fact, in this kind of application, C1 has to supply to the input pin the minimum allowed voltage
during the negative half wave. Obviously bigger C1 value, more constant the input voltage is and consequently smaller the output voltage ripple. For the right choice of the input capacitor, you have also to remember that increasing its value you will obtain an increased power dissipation, and a heatsink could be required. The right heatsink is determined by.