L4949E STMicroelectronics, L4949E Datasheet
L4949E
Specifications of L4949E
Available stocks
Related parts for L4949E
L4949E Summary of contents
Page 1
... Voltage sense comparator ■ Thermal shutdown and short circuit protections Description The L4949E is a monolithic integrated 5V voltage regulator with a very low dropout output and additional functions as power-on reset and input voltage sense designed for supplying the microcomputer controlled systems especially in automotive applications ...
Page 2
... Supply voltage transient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.2 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.3 Voltage regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.4 Preregulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.5 Reset circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.6 Sense comparator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4 Package and packing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.1 ECOPACK 4.2 SO-8 TP package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.3 SO-20 TP package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2/19 ® packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Doc ID 4275 Rev 6 L4949E ...
Page 3
... L4949E 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. Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 6. Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 7. Sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 8. Preregulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 9. SO-8 TP mechanical data Table 10. SO-20 TP mechanical data Table 11. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Doc ID 4275 Rev 6 ...
Page 4
... Configuration diagram (top view Figure 3. Application circuit Figure 4. Foldback characteristic of V Figure 5. Output voltage vs input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 6. Quiescent current vs supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 7. Block circuit of reset circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 8. Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 9. SO-8 TP package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 10. SO20 TP package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4/19 ( Doc ID 4275 Rev 6 L4949E ...
Page 5
... L4949E 1 Block diagram and pin description Figure 1. Block diagram Note: The block diagram illustrates only a major internal device functionality and it is not intended to mimic any details of hardware design Figure 2. Configuration diagram (top view) SO-8 Block diagram and pin description SO-20 Doc ID 4275 Rev 6 ...
Page 6
... Sense output. This open collector pin must be connected via an external resistor pulled down whenever O OUT the S voltage becomes lower than an internal voltage. I Output voltage. Block to GND via an external capacitor (see V OUT Figure 3) NC Not connected pins Doc ID 4275 Rev 6 L4949E Function 3). and to GND. S Section 3.4: ...
Page 7
... L4949E 2 Electrical specifications 2.1 Absolute maximum ratings Table 3. Absolute maximum ratings Symbol V DC operating supply voltage SDC V Transient supply voltage (T < 1s) STR I Output current O V Output voltage Output voltage RES Output current RES SO V Reset delay voltage CT V Sense input voltage ...
Page 8
... Min. Typ. Max. 4.95 5 5.05 < 4.90 5 5.10 4.75 5.25 0.1 0.25 0.2 0.4 0.3 0.5 0 200 105 400 120 400 100 200 300 5 Min. Typ. Max 0.5V 50 100 200 55 100 180 ≥ 1. 100 L4949E Unit µ µA mA Unit µ ...
Page 9
... L4949E Table 7. Sense Symbol Parameter V Sense low threshold st V Sense threshold hysteresis sth V Sense output low voltage SL I Sense output leakage SH I Sense input current SI Table 8. Preregulator Symbol Parameter V Preregulator output voltage Z I Preregulator output current Z Test condition ≤ 1. ≥ KΩ ...
Page 10
... This capacitor (C3 ≤ 1 µF) reduces also the output noise. 3.2 Functional description The L4949E is a monolithic integrated voltage regulator, based on the STM modular voltage regulator approach. Several outstanding features and auxiliary functions are implemented to meet the requirements of supplying microprocessor systems in automotive applications. ...
Page 11
... L4949E required. The modular approach of this device allows to get easily also other features and functions when required. 3.3 Voltage regulator The voltage regulator uses an Isolated Collector Vertical PNP transistor as a regulating element. Figure 4. Foldback characteristic of V With this structure very low dropout voltage at currents up to 100mA is obtained. The dropout operation of the standby regulator is maintained down to 3V input supply voltage ...
Page 12
... This output may be used as an option when a better transient behaviour for supply voltages less than required (see also application note). In this case a capacitor (100 µF) must be connected between pin V feature is not used pin V 12/19 ). This voltage should not be used as an output Z must be left open. Z Doc ID 4275 Rev 6 L4949E and GND. If this Z ...
Page 13
... L4949E 3.5 Reset circuit The block circuit diagram of the reset circuit is shown in supervises the output voltage. The reset threshold of 4 defined with the internal reference voltage and standby output drivider. The reset pulse delay time t • -------------------- - RD 2μA The reaction time of the reset circuit originates from the discharge time limitation of the reset capacitor CT and is proportional to the value of CT ...
Page 14
... Application information Figure 8. Waveforms 14/19 Doc ID 4275 Rev 6 L4949E ...
Page 15
... L4949E 4 Package and packing information ® 4.1 ECOPACK In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ® ECOPACK trademark. 4.2 SO-8 TP package information Table 9 ...
Page 16
... Package and packing information Figure 9. SO-8 TP package dimensions 4.3 SO-20 TP package information Table 10. SO-20 TP mechanical data Dim 16/19 mm Min. Typ. 2.35 0.1 0.33 0.23 12.6 7.4 1.27 10 Doc ID 4275 Rev 6 L4949E Max. 2.65 0.3 0.51 0.32 13 7.6 10.65 ...
Page 17
... L4949E Table 10. SO-20 TP mechanical data (continued) Dim Figure 10. SO20 TP package dimensions Package and packing information mm Min. Typ. 0.25 0.4 0 (min.)8 (max.) Doc ID 4275 Rev 6 Max. 0.75 1.27 17/19 ...
Page 18
... Document revision history Date 01-Jun-2000 25-Nov-2009 18/19 Revision 1 Initial release. Reformatted entire document. Removed Minidip package. Added Table 2: Pin definitions and 6 Updated Table 3: Absolute maximum ratings Updated Figure 1: Block diagram (1) circuit Doc ID 4275 Rev 6 Description of changes functions. and Figure 3: Application L4949E ...
Page 19
... L4949E 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. ...