TLV431AE5TA Diodes Inc, TLV431AE5TA Datasheet - Page 10

• Manufacturer Part Number: TLV431AE5TA
• Description: Voltage & Current References 1.24V 1% V-REF ADJ
• Manufacturer: Diodes Inc

Specifications of TLV431AE5TA

• 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
• Package / Case: SOT-23
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Application Information
Printed circuit board layout considerations (continued)
Figure 5 adds current limit to the series regulator in Figure 4 using a second TLV431. For currents below the limit, the circuit
works normally supplying the required load current at the design voltage. However should attempts be made to exceed the
design current set by the second TLV431, the device begins to shunt current away from the base of Q1. This begins to reduce
the output voltage and thus ensuring that the output current is clamped at the design value. Subject only to Q1’s ability to
withstand the resulting power dissipation, the circuit can withstand either a brief or indefinite short circuit.
One of the useful applications of the TLV431 is in using it to improve the accuracy and/or extend the range and flexibility of
fixed voltage regulators. In the circuit in Figure 6 above both the output voltage and its accuracy are entirely determined by the
TLV431, R1 and R2. However the rest of the features of the regulator (up to 5A output current, output current limiting and
thermal shutdown) are all still available.
TLV431
Document number: DS32088 Rev. 5 - 2
Figure 6. Increasing output voltage of a fixed linear regulator
(cont.)
Figure 5. Series regulator with current limit
www.diodes.com
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(All features of the regulator
such as short circuit
protection, thermal shutdown,
etc, are maintained.)
Diodes Incorporated
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V
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© Diodes Incorporated
TLV431
April 2011