Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272

POW-R-BRIK™

Phase Control Modules

345-800 Amperes/400-3000 Volts

P-3

Typical Thermistor Circuit

Thermistor temperatures can be

measured using the following

circuit arrangement in conjunction

with a 5 volt source. Resistance

values for R1 and R2 are specified

for two operating temperature

ranges.

POW-R-BRIK™ Thermistor

Characteristics

Element

Average

Thermistor Thermistor

Temperature

Resistance

Temp. Steady State Dynamic

Ohms

°C

°C (Min.)

°C (Max.)

Œ



Ž

12093

40

43

50

7337

50

53

60

4990

60

63

70

3324

70

73

80

2262

80

83

90

1569

90

93

100

1316

95

98

105

1109

100

103

110

938

105

108

115

797

110

113

120

680

115

118

125

582

120

123

130

500

125

128

135

431

130

133

140

Œ Curve matched ±2% over temperature range of +40°C

to +125°C. Resistance tolerance specified at +125°C,

±6%.

 Without self heating, 10mW maximum thermistor

dissipation.

Ž Use “Sensor at Tj” ohms from characteristics for

recommended steady state overload trip resistance.

1.

Temperature range, 75°C

through 125°C

R1 = 3.5K ohms

R2 = 840 ohms

V0 = 2.5 volts at 100°C

2.

Temperature range, 90°C

through 140°C

R1 = 2.2K ohms

R2 = 500 ohms

V0 = 2.45 volts at 115°C

The output signal (V0) is

approximately 30 mv/°C over the

temperature range indicated.

5 VOLT SUPPLY

THERMISTOR

GATES

POW-R-BRIK

CONTROL:

PROTECTION

CIRCUIT

TIME, t, (SECONDS)

TRANSIENT THERMAL IMPEDANCE

CHARACTERISTICS (JUNCTION-TO-CASE)

Z7A

PER ELEMENT,

BOTH CONDUCTING

PER ELEMENT,

ONE CONDUCTING

PER MODULE,

BOTH CONDUCTING

TIME, t, (SECONDS)

TRANSIENT THERMAL IMPEDANCE

CHARACTERISTICS (JUNCTION-TO-CASE)

Z9A

PER ELEMENT,

BOTH CONDUCTING

PER ELEMENT,

ONE CONDUCTING

PER MODULE,

BOTH CONDUCTING