STM1831 STMicroelectronics, STM1831 Datasheet
STM1831
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STM1831 Summary of contents
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... Operating temperature – °C Applications ■ Microprocessor reset circuitry ■ Charge voltage monitors ■ Memory battery backup switch circuits ■ Power failure detection circuits November 2010 Voltage detector with sense input and external delay capacitor Doc ID 18180 Rev 1 STM1831 SOT23-5 1/24 www.st.com 1 ...
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... Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1 Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 Typical operating characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 6 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 7 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 8 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 2/24 Doc ID 18180 Rev 1 STM1831 ...
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... List of tables Table 1. Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Table 2. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 3. Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 4. DC and AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 5. SOT23-5 - 5-lead small outline transistor package mechanical data . . . . . . . . . . . . . . . . . 21 Table 6. STM1831 ordering information scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 7. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Doc ID 18180 Rev 1 List of tables 3/24 ...
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... SEN CC pin open . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SEN RST = 25 ° ° 6 pin open . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SEN = V CC SEN Doc ID 18180 Rev °C, external pull-up resistor = 0 SEN 6.0 V, SEN = STM1831 ...
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... STM1831 1 Description The STM1831 is a voltage detector with very low current consumption. It monitors a voltage on a separate input pin (V down addition, the delay of the output can be adjusted by an external capacitor. Figure 1. Logic diagram . Table 1. Pin descriptions Pin 1 Output open drain ...
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... Reset output is asserted when the voltage on the DET The STM1831 has an open drain, active-low output which sinks current when the output is asserted. Connect a pull-up resistor from RST to any supply voltage (see Figure 4). Select a resistor value large enough to register a logic low, and small enough to register a logic high, while all of the input current and leakage paths connected to the reset output line are being supplied kΩ ...
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... Application hookup 1. External pull-up resistor is needed for open drain RST output kΩ is sufficient in most applications. V Logic REF Monitored V SEN voltage STM1831 Doc ID 18180 Rev (1) RST Description RST V SS AM00853 AM00699 ...
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... Operation 2 Operation The STM1831 voltage detector monitors system voltages from 1 5 100 mV increments, has a voltage hysteresis (V capacitor The STM1831 asserts a reset output (RST) whenever The reset output stays asserted until V DET hysteresis (V DET output deassertion is adequately delayed (see details) ...
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... STM1831 3 Typical operating characteristics Figure 6. Supply current vs. sense voltage, V 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0 Figure 7. Supply current vs. input voltage, V 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0 Sense voltage, V SEN = 1.9 V (RST asserted) SEN Supply voltage Doc ID 18180 Rev 1 Typical operating characteristics = 2.0 V DET –40 ° ° ° ...
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... Figure 8. Detect voltage vs. ambient temperature, V 2.50 2.45 2.40 2.35 2.30 -40 Figure 9. Detect voltage vs. supply voltage, V 2.50 2.45 2.40 2.35 2.30 1 10 Ambient temperature, T DET ° Supply voltage Doc ID 18180 Rev 1 STM1831 = 2.4 V DET (°C) A AM04967v1 = 2 ° -40 ° (V) AM04968v1 ...
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... STM1831 Figure 10. Hysteresis voltage vs. ambient temperature, V 300 250 200 150 100 50 0 -40 Figure 11. C pin sink current vs. supply voltage Ambient Temperature Supply voltage, V Doc ID 18180 Rev 1 Typical operating characteristics = 2 ...
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... DET pin open Sense voltage, V SEN SEN pin open -40 ° ° °C 0.5 1 1.5 Supply voltage, V Doc ID 18180 Rev 1 STM1831 = 2 °C, external pull (V) AM04971v1 = V , external pull-up resistor CC 2 2.5 (V) CC ...
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... STM1831 Figure 14. Output current vs. supply voltage Figure 15. Relative delay resistance vs. ambient temperature 1.30 1.20 1.10 1.00 0.90 0.80 0. Supply voltage -40 - Ambient temperature, T Doc ID 18180 Rev 1 Typical operating characteristics = 0.5 V SEN RST -40 ° ° ° ...
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... Figure 17. Detect delay time vs. delay capacitance, T 10000 1000 100 10 14/ 1 0.0001 0.001 0.01 External delay capacitor 1 0.0001 0.001 0.01 External delay capacitor, C Doc ID 18180 Rev 1 STM1831 = 25 °C A 0.1 1 (µF) D AM04975v1 = 25 °C A 0.1 1 (µF) D AM04976v1 ...
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... STM1831 Figure 18. RST output leakage current vs. ambient temperature 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 Figure 19. RST output leakage current vs. output voltage ° 0.6 0.5 0.4 0.3 0 pin open SEN OUT D - Ambient temperature, T pin open Reset output voltage, V Doc ID 18180 Rev 1 ...
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... Figure 21. Sense current vs. ambient temperature, V 500 450 400 350 300 250 200 150 100 50 0 16/ Supply voltage, V -40 - Ambient temperature, T Doc ID 18180 Rev 1 = 1.9 V SEN -40 ° ° ° ( SEN (°C) A STM1831 AM04979v1 AM04980v1 ...
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... STM1831 4 Maximum ratings Stressing the device above the ratings listed in 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. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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... Input and output timing ref. voltages Figure 22. AC testing input/output waveforms 0 0 18/24 Table 4 and t . Designers should check that the operating DET REL Parameter ) ) A Doc ID 18180 Rev 1 STM1831 that follow, are derived from tests Table 3 and Figure 5 with Value Unit 1.6 to 6.0 V – °C ≤ 0.2 to 0.8 V ...
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... STM1831 Table 4. DC and AC characteristics Symbol Parameter Operating V CC voltage V Detect voltage DET Hysteresis V HYS voltage I Supply current CC I Output current RST Output leakage I LEAK current Temperature ΔV / (ΔT • DET A DET variation I Sense current SEN R Delay resistance CD Delay I capacitance pin ...
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... ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ® ECOPACK trademark. The maximum ratings related to soldering conditions are also marked on the inner box label. 20/24 Doc ID 18180 Rev 1 STM1831 ® ...
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... STM1831 Figure 23. SOT23-5 - 5-lead small outline transistor package mechanical drawing Note: Drawing is not to scale. Table 5. SOT23-5 - 5-lead small outline transistor package mechanical data Symbol Typ 1. 2.90 E 2.80 E1 1.60 e 0.95 e1 1.90 L 0.45 θ Millimeters Min. Max. 1.45 0.00 0.15 0.90 1.30 0.30 0.50 0.08 0.22 0.30 0. Doc ID 18180 Rev 1 ...
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... Part numbering 7 Part numbering Table 6. STM1831 ordering information scheme Example: Device type STM1831 Reset output polarity L: active-low Detector threshold 24: 2.4 V typ. (100 mV steps from 1 5.7 V available) Package WY: SOT23-5 Temperature range 6: –40 °C to +85 °C Shipping method F: Lead-free ECOPACK 1. Other detector thresholds are offered. Minimum order quantities may apply. Contact local ST sales office for availability ...
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... STM1831 8 Revision history Table 7. Document revision history Date 16-Nov-2010 Revision 1 Initial release. Doc ID 18180 Rev 1 Revision history Changes 23/24 ...
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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 24/24 Please Read Carefully: © 2010 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 18180 Rev 1 STM1831 ...