LM338 STMicroelectronics, LM338 Datasheet
LM338
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LM338 Summary of contents
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... Current limit constant with temperature ■ Standard 3-lead transistor package Description The LM138, LM238, LM338 are adjustable 3- terminal positive voltage regulators capable of supplying in excess over a 1 output range. They are exceptionally easy to use and require only 2 resistors to set the output voltage ...
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Contents 1 Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Diagram 1 Figure 1. Schematic diagram 3/23 ...
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Pin configuration Figure 2. Pin connections (top view) 4/23 TO-3 ...
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... Absolute maximum ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. Table 3. Thermal data Symbol R Thermal resistance junction-case thJC R Thermal resistance junction-ambient thJA Parameter LM138 LM238 LM338 Parameter Value Unit 35 V Internally limited -65 to 150 °C 300 °C -55 to 150 -25 to 125 °C ...
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Electrical characteristics Table 4. Electrical characteristics for LM138/LM238 Symbol Parameter (2) K Line regulation VI (2) K Load regulation VO Thermal regulation I Adjustment pin current ADJ Adjustment pin current ΔI ADJ change V Reference voltage REF (2) K ...
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... Table 5. Electrical characteristics for LM338 Symbol Parameter (2) K Line regulation VI (2) K Load regulation VO Thermal regulation I Adjustment pin current ADJ Adjustment pin current ΔI ADJ change V Reference voltage REF (2) K Line regulation VI (2) K Load regulation VO K Temperature stability VT I Minimum load current ...
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Typical characteristics Figure 3. Current limit Figure 5. Current limit 8/23 Figure 4. Current limit Figure 6. Load regulation ...
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Figure 7. Dropout voltage Figure 9. Temperature stability Figure 8. Adjustment current Figure 10. Output impedance 9/23 ...
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Figure 11. Minimum operating current Figure 13. Ripple rejection 10/23 Figure 12. Ripple rejection Figure 14. Ripple rejection ...
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Figure 15. Line transient response Figure 16. Load transient response 11/23 ...
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Typical application Figure 17. 1 adjustable regulator Needed if device is far from filter capacitors. * Optional-improves transient response. Output capacitors in the range of 1mF to 100mF of aluminium or tantalum electrolytic are commonly ...
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... Figure 18. Application circuit Since the 50 µA current from the adjustment terminal represents an error term, the LM338 was designed to minimize I this, all quiescent operating current is returned to the output establishing a minimum load current requirement. If there is insufficient load on the output, the output will rise. ...
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... Although the LM338 is stable with no output capacitors, like any feedback circuit, certain values of external capacitance can cause excessive ringing. This occurs with values between 500 pF and 5000 pF solid tantalum (or 25 µF aluminium electrolytic) on the output swamps this effect and insures stability. ...
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Figure 19. Regulator with line resistance in output lead Figure 20. Regulator with protection diodes 15/23 ...
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Figure 21 regulator * Minimum load - 100 mA ≥ ≥ ≥ 3 Figure 22 current regulator * Minimum load - 100 ...
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Figure 23 regulator * Minimum load - 100mA ≥ ≥ ≥ 17/23 ...
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Figure 24 logic regulator with electronic shutdown = 240 Ω for LM138 or LM238 * 720 Ω for LM138 or LM238 * Minimum load - 100 mA Figure 25. Tracking pre-regulator = ...
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Figure 26. Slow turn- regulator = 240 Ω for LM138 or LM238 * 2.7 kΩ for LM138 or LM238 2 19/23 ...
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Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
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TO-3 mechanical data mm. Dim. Min. Typ. A 11.85 B 0.96 1. 10 30.10 Max. Min. 1.10 0.037 1.70 8.7 20.0 26.2 4.09 0.152 39 ...
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Revision history Table 6. Document revision history Date Revision 16-Apr-2003 1 11-Apr-2008 2 22/23 Changes First release. Added: Table 1 on page 1. ...
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... Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...