L4938ED STMicroelectronics, L4938ED Datasheet
L4938ED
Specifications of L4938ED
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L4938ED Summary of contents
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... Output 2 disable function for standby mode March 2010 Advanced voltage regulator Description The L4938ED and L4938EPD are monolithic ) integrated dual voltage regulators with two very low dropout outputs and additional functions such as power-on reset and input voltage sense. They are designed for supplying microcomputer controlled systems especially in automotive applications ...
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... Reset circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.5 Sense comparator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.6 Thermal protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.7 Transient sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.8 Input protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4 Package and packing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.1 ECOPACK 4.2 SO-20 package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.3 PowerSO-20 package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2/20 ® packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Doc ID 17243 Rev 1 L4938ED, L4938EPD ...
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... L4938ED, L4938EPD List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Pin definitions and functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 4. Thermal data Table 5. OUT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 6. OUT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 7. OUT1, OUT2 Table 8. Enable input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 9. Reset circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 10. Sense comparator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Table 11. SO-20 mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 12. ...
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... List of figures Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Figure 2. Configuration diagram (top view Figure 3. Application diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 4. OUT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 5. Reset generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 6. Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 7. Input protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 8. Input characteristics of SI Figure 9. SO-20 package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 10. PowerSO-20 package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4/20 Doc ID 17243 Rev 1 L4938ED, L4938EPD ...
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... L4938ED, L4938EPD 1 Block diagram and pin description Figure 1. Block diagram Figure 2. Configuration diagram (top view GND GND GND GND RES SO OUT1 GND N. GND GND GND GND N. OUT2 N. ADJ GND SO-20 Doc ID 17243 Rev 1 Block diagram and pin description 1 20 GND ...
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... CT Reset delay capacitor 8 EN Enable (low activates the 400 mA regulator) 1, 10, 11, 20 GND Ground 14 RES Reset output 15 SO Sense output 16 OUT1 100 mA regulator output 17 ADJ Feedback of 400 mA regulator 18 OUT2 400 mA regulator output Not connected Doc ID 17243 Rev 1 L4938ED, L4938EPD Function ...
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... L4938ED, L4938EPD 2 Electrical specifications 2.1 Absolute maximum ratings Stressing the device above the ratings listed in the “Absolute maximum ratings” tables may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the Operating sections of this specification is not implied ...
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... 100 mA OUT2 I = 400 mA; V OUT2 400 mA OUT1 (after regulation setting 0 100 mA; OUT1 I = 400 mA OUT2 Doc ID 17243 Rev 1 L4938ED, L4938EPD SO-20 PowerSO- < 2 copper ground plane (35 mm thick). Min. Typ. Max. Unit 4.9 5 4.8 5 0.1 = 4.8 V 0.2 S 100 200 65 > 1.3 V ...
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... L4938ED, L4938EPD Table 7. OUT1, OUT2 Symbol V Line regulation OLi 1,2 Table 8. Enable input Symbol Enable input low voltage V ENL (output 2 active) V Enable input high voltage ENH V Enable hysteresis ENhyst I Enable input current low EN LOW I Enable input current high EN HIGH Table 9. Reset circuit ...
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... Parameter Test condition Falling edge; T Falling edge; T < 130 to 150 °C J ≤ 1. connected 1 1 < 130 to 150 ° Doc ID 17243 Rev 1 L4938ED, L4938EPD Min. Typ. Max. -20 < 130 °C 1.08 1.16 J 1.05 1. KΩ SO ≥ ≥ 1 < 130 ° -10 0 -20 -8 Unit ...
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... V or -20 V can not be guaranteed. 3.1 Functional description The L4938ED and L4938EPD are monolithic integrated dual voltage regulators, based on the STM modulator voltage regulator approach. Several outstanding features and auxiliary functions are implemented to meet the requirements of supplying microprocessor systems in automotive applications ...
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... R 1E ⎜ ------------------------------------------------ - OUT2 OUT1 ⎝ = 4.95 to 5.05 V. For an exact calculation the OUT1 - 2000 pprm) of the internal resistor ( lacking, the reset generator is supplied by the output voltage S Doc ID 17243 Rev 1 L4938ED, L4938EPD ( ) ⎞ ADJ ⎟ ⋅ ⎠ ADJ ) must be taken into ADJ (a) and standby ...
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... L4938ED, L4938EPD The value of the programming resistor R The reset pulse delay time t The reaction time of the reset circuit originates from the noise immunity. Standby output voltage drops below the reset threshold only a bit longer than the reaction time results in a shorter reset delay time. The nominal reset delay time is generated for standby output voltage drops longer than approximately 50 µ ...
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... Application information Figure 5. Reset generator Figure 6. Waveforms 14/20 Doc ID 17243 Rev 1 L4938ED, L4938EPD ...
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... L4938ED, L4938EPD 3.8 Input protection The Inputs Enable (EN) and Sense In (SI) are protected against negative transients. Figure 7 is showing the simplified schematic Figure 7. Input protection Figure 8. Input characteristics of SI, EN Doc ID 17243 Rev 1 Application information 15/20 ...
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... ECOPACK trademark. 4.2 SO-20 package information Table 11. SO-20 mechanical data Dim 16/20 packages Min. 2.35 0.1 0.33 0.23 12.6 7.4 10 0.25 0.4 0° Doc ID 17243 Rev 1 L4938ED, L4938EPD mm Typ. Max. 2.65 0.3 0.51 0.32 13 7.6 1.27 10.65 0.75 1.27 8° ® ...
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... L4938ED, L4938EPD Figure 9. SO-20 package dimensions 4.3 PowerSO-20 package information Table 12. PowerSO-20 mechanical data Dim ( ( Package and packing information mm Min. Typ. 0.1 0 0.4 0.23 15.8 9.4 13.9 1.27 11.43 10.9 5.8 Doc ID 17243 Rev 1 Max. 3.6 0.3 3.3 0.1 0.53 0. ...
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... Critical dimensions: "E", "G" and "a3" Figure 10. PowerSO-20 package dimensions 45˚ 18/20 Min. 0 15.5 0 DETAIL PSO20MEC Doc ID 17243 Rev 1 L4938ED, L4938EPD mm Typ. Max. 15 DETAIL B E DETAIL A lead slug a3 DETAIL B 0.35 Gage Plane S SEATING PLANE L BOTTOM VIEW (COPLANARITY 0.1 1.1 1.1 10° ...
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... L4938ED, L4938EPD 5 Revision history Table 13. Document revision history Date 10-Mar-2010 Revision 1 Initial release. Doc ID 17243 Rev 1 Revision history Changes 19/20 ...
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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 20/20 Please Read Carefully: © 2010 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 17243 Rev 1 L4938ED, L4938EPD ...