LT1123 LINER [Linear Technology], LT1123 Datasheet
LT1123
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LT1123 Summary of contents
Page 1
... LT1123. The drive current of the LT1123 is folded back as the feedback pin approaches ground to further limit the available drive current under short circuit conditions. Total quiescent current for the LT1123 is only 700 A. The device is available in a low cost TO-92 package. MOTOROLA MJE1123 ...
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... DRIVE 100mA DRIVE W DRIVE – + CURRENT LIMIT THERMAL LIMIT GROUND U W ORDER PART BOTTOM VIEW NUMBER GND LT1123CZ Z PACKAGE MIN TYP MAX 4.90 5.00 5.10 4.80 5.00 5.20 300 500 0.45 1.0 125 170 25 100 150 1.4 2.0 1.0 20 –5 –50 0 LT1123 SBD01 U UNITS mV/ C ...
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... FEEDBACK PIN VOLTAGE (V) LT1123 G04 CTIO AL DESCRIPTIO The LT1123 is a three pin device designed to be used in conjunction with a discrete PNP transistor to form an inexpensive ultra-low dropout regulator. The device incor- porates a trimmed 5V bandgap reference, error amplifier, a current-limited Darlington driver, and an internal ther- mal limit circuit ...
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... A PPLICATI S I FOR ATIO The LT1123 is designed to be used in conjunction with an external PNP transistor. The overall specifications of a regulator circuit using the LT1123 and an external PNP will be heavily dependent on the specifications of the external PNP. While there are a wide variety of PNP transistors ...
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... PPLICATI S I FOR ATIO A output at 5V. The drive pin of the LT1123 can only sink current required to provide pullup on the base of the B PNP. R must be sized so that the voltage drop caused by B the minimum drive pin current is less than the emitter/ base voltage of the external PNP at light loads ...
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... Selection Chart lists the recommended values for D based on the R for the most useful range of input voltage and output D D current. The chart includes a number for power dissipa- tion for the LT1123 and R R Selection Chart D INPUT OUTPUT CURRENT: VOLTAGE DROPOUT VOLTAGE: + 1mA) 5 ...
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... Figure 6. MJE1123 The curve in Figure 6 can be used to determine the range of current limit of an LT1123 regulator circuit using an MJE1123 as a pass transistor. The curve was generated using the Beta versus I minimum and maximum value curves are extrapolated from the minimum and maximum Beta specifications. ...
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... DRIVE The maximum junction temperature rise above ambient for the LT1123 will be equal to the worst case power dissipation multiplied by the thermal resistance of the device. The thermal resistance of the device will depend upon how the device is mounted, and whether a heat sink is used ...
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... S I FOR ATIO A THERMAL LIMITING The thermal limit of the LT1123 can be used to protect both the LT1123 and the PNP pass transistor. This is accom- plished by thermally coupling the LT1123 to the power transistor. There are clip type heat sinks available for the TO-92 package that will allow the LT1123 to be mounted to the same heat sink as the PNP pass transistor ...
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... DRIVE REMOTE LT1123 FB LOAD GND 100 Undervoltage Indicator On for V < (V +5V 2. DRIVE LT1123 FB 470k GND LT1123 TA12 Battery Backup Regulator + 10µF 620 620 ALUM MJE1123 MJE1123 1N4148 1N4148 20 DRIVE 5V OUTPUT LT1123 GND ALUM + 100 F OR LARGER LT1123 TA08 ...
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... V Z ALUM R1 1. LT1123 TA13 R2 820 DRIVE LT1123 GND V * OUT + 10µF ALUM • LT1123 TA14 LT1123 5V/1A Regulator with Shutdown 620 1M Si9400DY* 1/6 MM74C906 (OPEN COLLECTOR 68 OUTPUT) DRIVE 5V/1A OUTPUT LT1123 GND ALUM + + MJE1123 10V * PACKS WILL SHARE CURRENT ...
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... LT1123 PACKAGE DESCRIPTIO 0.060 ± 0.005 (1.524± 0.127) DIA 0.180 ± 0.005 (4.572 ± 0.127) 0.500 (1.270) (12.79) MIN UNCONTROLLED LEAD DIA 0.050 ± 0.005 (1.270 ± 0.127) Linear Technology Corporation 12 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 : (408) 434-0507 FAX ...