PRF21BB471QB5RA Murata, PRF21BB471QB5RA Datasheet - Page 13

• Manufacturer Part Number: PRF21BB471QB5RA
• Description: Thermistors - PTC 470 Ohm 50% 32volts
• Manufacturer: Murata
• Type: PTCr

Specifications of PRF21BB471QB5RA

• Resistance: 470 Ohms
• Tolerance: 50 %
• Termination Style: SMD/SMT
• Operating Temperature Range: - 20 C to + 130 C
• Dimensions: 1.25 mm W x 2 mm L x 0.9 mm H
• Voltage: 32 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

!Note
Chip POSISTORr: PRG series
1. Applications
See below figures.
2. Benefits
3. Recommended part numbers
PRG21BC0R6MM1RA
PRG21BC0R2MM1RA
PRG21BC1R0MM1RA
PRG21BC2R2MM1RA
PRG21BC3R3MM1RA
PRG21BC6R8MM1RA
PRG21BC4R7MM1RA
*Curie Point means the temperature at which the resistance value reaches twice the resistance at 25 C.
Please ask for details.
Current Limiter for LED
POSISTORr is an effective current limit solution based
on LED's allowable current and temperature
characteristics.
(1) LED lighting instruments
(2) LED backlight of flat displays
(1) Higher LED brightness versus a fixed resistor. LED
(2) LED lifetime may be extended due to the current
(3) Small 0805 package allows the POSISTORr to be
Choose an appropriate part number having max. voltage
and resistance value. Review the protective threshold
current range based on the operating current and
temperature of the LED.
• Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this catalog to prevent smoking and/or burning, etc.
• This catalog has only typical specifications because there is no space for detailed specifications. Therefore, please review our product specifications or consult the approval sheet for product specifications before ordering.
Part Number
can work in the smaller series resistance with
POSISTORr at normal operation temperature. The
number of LEDs is possibly reduced.
limiting function of the POSISTORr in cases of
overheat or overcurrent situation.
placed close to the LED. It offers accurate detection of
ambient temperature near LED and increases
flexibility of packaging.
LED Driving Circuit
IC
Voltage
Max.
(V)
12
16
20
24
24
6
6
Current
Max.
6.5
6.0
3.5
5.0
(A)
10
10
10
IC
Hold Current
(at +60 C)
(mA)
285
500
220
150
120
100
80
Trip Current
(at -10 C)
1100
2000
(mA)
850
600
480
320
400
Allowable LED
Working Zone
Ambient Temp.
Protected by
POSISTORr
Resistance
(at +25 C)
0.6 20%
0.2 20%
1.0 20%
2.2 20%
3.3 20%
6.8 20%
4.7 20%
(ohm)
LED Current
Allowable LED
Working Zone
Ambient Temp.
Application Notes
Higher brightness vs.
a fixed resistor
Curie Point
( C) *
90
90
90
90
90
90
90
Current Limit by
a fixed resistor
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Details
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11
Apr.25,2011
R90E.pdf