STM809, STM810 STM811, STM812 Reset Circuit FEATURES SUMMARY ■ ■ ■ ■ ■ ■ ■ PRECISION MONITORING OF 3V, 3.3V, and 5V SUPPLY VOLTAGES TWO OUTPUT CONFIGURATIONS – Push-pull RST Output (STM809/811) – Push-pull RST Output (STM810/812) 140ms RESET PULSE WIDTH (MIN) LOW SUPPLY CURRENT - 6µA (TYP) GUARANTEED RST/RST ASSERTION DOWN TO VCC = 1.0V OPERATING TEMPERATURE: –40°C to 85°C (Industrial Grade) LEAD-FREE, SMALL SOT23 and SOT143 PACKAGE Figure 1. Packages SOT23-3 (WX) Table 1.
STM809/810/811/812 TABLE OF CONTENTS FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 1. Device Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 1. Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SUMMARY DESCRIPTION . . . . . . . . . . . . . .
STM809/810/811/812 Table 8. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Table 9. Marking Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 REVISION HISTORY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 10. Document Revision History . . . . . . . . . . . . . . . . . . . . . .
STM809/810/811/812 SUMMARY DESCRIPTION The STM809/810/811/812 MICROPROCESSOR RESET Circuits are low-power supervisory devices used to monitor power supplies. They perform a single function: asserting a reset signal whenever the VCC supply voltage drops below a preset value and keeping it asserted until VCC has risen above the preset threshold for a minimum period of time (trec). The STM811/812 also provide a push-button reset input (MR). Figure 2. Logic Diagram (STM809/810) Table 2.
STM809/810/811/812 Figure 7. Hardware Hookup VCC VCC VCC STM809/810/ 811/812 MCU MR(2) RST(1) Push-button RESET VSS RESET Input VSS AI07836 Note: 1. STM809/811 only (RST for STM810/812) 2.
STM809/810/811/812 OPERATION Reset Output The STM809/810/811/812 MICROPROCESSOR RESET CIRCUIT asserts a reset signal to the MCU whenever VCC goes below the reset threshold (VRST), or when the push-button reset input (MR) is taken low (see Figure 15., page 11). RST (active high for STM810/812) is guaranteed valid down to VCC = 1V (0° to 70°C). During power-up, once VCC exceeds the reset threshold an internal timer keeps RST low for the reset time-out period, trec. After this interval, RST returns high.
STM809/810/811/812 TYPICAL OPERATING CHARACTERISTICS Note: Typical values are at TA = 25°C, VCC = 5V for L/M versions, VCC = 3.3V for T/S versions, and VCC = 3.0V for R versions. Figure 8. Supply Current vs. Temperature, L/M/R/S/T (no load) 8.0 Supply Current (µA) 6.0 1V 3V 3.6V 5.5V 4.0 2.0 0.0 –40 –20 0 20 40 60 80 Temperature (˚C) AI07879 Figure 9. Power-down Reset Delay vs. Temperature - VOD = VTH – VCC (L/M) Power-Down Reset Delay (µs) 140.00 120.00 100.
STM809/810/811/812 Figure 10. Power-down Reset Delay vs. Temperature - VOD = VTH – VCC (R/S/T) Power-Down Reset Delay (µs) 100.00 80.00 60.00 VOD = 20mV VOD = 125mV VOD = 200mV 40.00 20.00 0.00 –40 –20 0 20 40 60 80 Temperature (˚C) AI07878 Figure 11. Power-up trec vs. Temperature 250.00 Power-up trec (ms) 240.00 230.00 L/M R/S/T 220.00 210.00 200.
STM809/810/811/812 Figure 12. Normalized Reset Threshold vs. Temperature 1.003 1.002 1.001 Normalized Treshold 1.000 0.999 0.998 L/M R/S/T 0.997 0.996 0.995 0.994 0.993 –40 –20 0 20 40 60 80 Temperature (˚C) AI07882 Figure 13. Max Transient Duration NOT Causing Reset Pulse vs. Reset Comparator Overdrive 700.00 Maximum Transient Duration (µs) 600.00 500.00 400.00 R/S/T L/M 300.00 200.00 100.00 0.
STM809/810/811/812 MAXIMUM RATING Stressing the device above the rating listed in the Absolute Maximum Ratings” table 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 im- plied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability.
STM809/810/811/812 DC AND AC PARAMETERS This section summarizes the operating measurement conditions, and the DC and AC characteristics of the device. The parameters in the DC and AC characteristics Tables that follow, are derived from tests performed under the Measurement Conditions summarized in Table 4., Operating and AC Measurement Conditions. Designers should check that the operating conditions in their circuit match the operating conditions when relying on the quoted parameters. Table 4.
STM809/810/811/812 Table 5. DC and AC Characteristics Sym Alternative Description VCC Operating Voltage ICC VCC Supply Current VIH MR Input High Voltage VIL MR Input Low Voltage VOL RST Output Low Voltage (Active High(2) or Low) VOL RST Output Low Voltage RST Output High Voltage VOH RST Output High Voltage Test Condition(1) Min TA = –40 to +85°C TA = 0 to +70°C Typ Max Unit 1.2 5.5 V 1.0 5.5 V VCC < 3.6V 5.5 10 µA VCC < 5.5V 7 15 µA VCC > VRST (max), STM8XXL/M 2.
STM809/810/811/812 PACKAGE MECHANICAL Figure 16. SOT23-3 – 3-lead Small Outline Transistor Package Outline E E1 0.15 B M CAB A1 1 e e1 D 0.20 M 3X CAB A2 0.10 C A 3X b C A C θ L1 C L SOT23-3 Note: Drawing is not to scale. Table 6. SOT23-3 – 3-lead Small Outline Transistor Package Mechanical Data mm inches Symbol Typ Min Max A 0.89 A1 Min Max 1.12 0.035 0.044 0.01 0.10 0.001 0.004 A2 0.88 1.02 0.035 0.042 b 0.30 0.50 0.012 0.020 C 0.08 0.20 0.003 0.
STM809/810/811/812 Figure 17. SOT143-4 – 4-lead Small Outline Transistor Package Outline E E1 0.15 B M CAB A1 1 e/2 e1 e D 0.15 M CAB b2 0.20 M 4X CAB 3X b A2 C 0.10 A C A C θ L1 C L SOT143-4 Note: Drawing is not to scale. Table 7. SOT143-4 – 4-lead Small Outline Transistor Package Mechanical Data mm inches Symbol Typ 14/18 Min Max A 0.89 A1 Typ Min Max 1.12 0.035 0.044 0.01 0.10 0.001 0.004 A2 0.88 1.02 0.035 0.042 b 0.37 0.51 0.015 0.020 b2 0.
STM809/810/811/812 PART NUMBERING Table 8. Ordering Information Scheme Example: STM8XX L WX 6 F Device Type STM8XX Reset Threshold Voltage L = VRST = 4.50V to 4.75V M = VRST = 4.25V to 4.50V T = VRST = 3.00V to 3.15V S = VRST = 2.85V to 3.00V R = VRST = 2.55V to 2.70V Package WX = SOT23-3 (STM809, STM810) W1 = SOT143-4 (STM811, STM812) Temperature Range 6 = –40 to 85°C Shipping Method F = Pb-Free Package (ECO PACK®), Tape & Reel For a list of available options (e.g.
STM809/810/811/812 Table 9. Marking Description 16/18 Part Number Reset Threshold Output Topside Marking STM809L 4.63V Push-Pull RST 8AAx STM809M 4.38V Push-Pull RST 8ABx STM809T 3.08V Push-Pull RST 8ACx STM809S 2.93V Push-Pull RST 8ADx STM809R 2.63V Push-Pull RST 8AEx STM810L 4.63V Push-Pull RST 8AFx STM810M 4.38V Push-Pull RST 8AGx STM810T 3.08V Push-Pull RST 8AHx STM810S 2.93V Push-Pull RST 8AJx STM810R 2.63V Push-Pull RST 8AKx STM811L 4.
STM809/810/811/812 REVISION HISTORY Table 10. Document Revision History Date Version Revision Details 02-Sep-03 1.0 First Issue 03-Oct-03 1.1 Update Operating Characteristics (Figure 8, 9, 10, 11, 12, 13) 16-Oct-03 1.2 Update characteristics (Table 5); modify illustration (Figure 13) 17-Nov-03 1.3 Modified with JEDEC timing symbols (Figure 15; Table 5) 04-Dec-03 2.0 Reformatted; promoted; updated (Figure 15; Table 5, 6) 09-Dec-03 2.
STM809/810/811/812 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice.
