TLV431AFTA Diodes Inc, TLV431AFTA Datasheet - Page 9

• Manufacturer Part Number: TLV431AFTA
• Description: Voltage & Current References 1.24V 1% V-REF ADJ
• Manufacturer: Diodes Inc

Specifications of TLV431AFTA

• Product: Voltage References
• Topology: Shunt References
• Output Voltage: 1.24 V to 18 V
• Initial Accuracy: 1 %
• Series Vref - Input Voltage (max): 20 V
• Shunt Current (max): 15 mA
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Reference Type: Adjustable
• Package / Case: SOT-23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Application Information
Printed circuit board layout considerations
The TLV431 in the SOT25 package has the die attached to pin 2, which results in an electrical contact between pin 2 and pin
5. Therefore, pin 2 of the SOT25 package must be left floating or connected to pin 5.
TLV431 in the SC70-6 package has the die attached to pin 2 and 5, which results in an electrical contact between pins 2, 5
and pin 6. Therefore, pins 2 and 5 must be left floating or connected to pin 6.
Other applications of the TLV431
It may at times be required to shunt-regulate more current than the 15mA that the TLV431 is capable of.
Figure 3 shows how this can be done using transistor Q1 to amplify the TLV431’s current. Care needs to be taken that the
power dissipation and/or SOA requirements of the transistor is not exceeded.
A very effective and simple series regulator can be implemented as shown in Figure 4 above. This may be preferable if the
load requires more current than can be provided by the TLV431 alone and there is a need to conserve power when the load is
not being powered. This circuit also uses one component less than the shunt circuit shown in Figure 3 above.
TLV431
Document number: DS32088 Rev. 5 - 2
(cont.)
Figure 3. High current shunt regulator
Figure 4. Basic series regulator
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© Diodes Incorporated
TLV431
April 2011