TS3809/3810 Series Microprocessor Reset Circuit SOT-23 Pin Definition: TS3809 TS3810 1. GND 1. GND 2. RESET 2. (RESET) 3. VCC 3. VCC General Description The TS3809/3810 series are used for microprocessor (µP) supervisory circuits to monitor the power supplies in µ P and digital systems. They provide excellent circuit reliability and low cost by eliminating external components and adjustments when used with +5V, +3.3V, +3.0V, +2.5V powered circuits. These circuits perform a single function: they assert a reset signal whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for at least 200ms after VCC has risen above the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available. TS3809/3810 series have push pull outputs. TS3809 series have an active low RESET output, while the TS3810 has an active high RESET output The reset comparator is designed to ignore fast transients on VCC, and the outputs are guaranteed to be in the correct logic state for VCC down to 1.0V. Low supply current makes TS3809/3810 series ideal for use in portable equipment. Features ● ● ● ● ● ● ● ● ● ● Ordering Information High Accurate: ±2% Precision monitoring of +3V, +3.3V and +5V Power supply voltage Fully specified over temperature Available in three output configurations Push-Pull RESET low output (TS3809) Push-Pull (RESET) high output (TS3810) 200mS typ. Power-on reset pulse width 25µS supply current Guaranteed reset valid to Vcc=+1V Power supply transient immunity Part No. TS3809CXx RF Package Packing SOT-23 3Kpcs / 7” Reel 3Kpcs / 7” Reel TS3810CXx RF SOT-23 Note: x is the threshold voltage type, option as: A : 4.63V B : 4.38V C : 4.00V D : 3.08V E : 2.93V F : 2.63V G : 2.25V Typical Application Circuit Applications ● ● ● ● ● Battery-operated systems and Controllers Intelligent instruments Critical uP and uC power monitoring Portable / Battery powered equipment Automotive Absolute Maximum Rating Parameter Symbol Maximum Unit VCC VRESET GND - 0.3 to GND +6.5 GND - 0.3 to VCC +0.3 V V Input Current, VCC Output Current, RESET, (RESET) ICC IO 20 5 mA mA Power Dissipation Operating Junction Temperature Range Storage Temperature Range PD TJ.OPR TSTG (TJ-TA)/θJA -40 ~ +125 -65 ~ +150 mW o C o C TLEAD 10 S Terminal Voltage (with respect to Gnd) RESET & (RESET) push-pull o Lead Soldering Temperature (260 C) 1/7 Version: C07 TS3809/3810 Series Microprocessor Reset Circuit Thermal Performance Parameter Symbol Maximum Unit θJC 110 ºC/W θJA 250 ºC/W Thermal Resistance from Junction to Case Thermal Resistance from Junction to ambient 2 Note: θ JA is measured the PCB copper area of approximately 1in (Multi-layer). Needs to connect to VSS pin. Electrical Specification (Ta = 25oC, unless otherwise specified.) Parameter Conditions o o Symbol Min Typ Max Unit Input Supply Voltage Ta=-40 C~+85 C VCC 1.0 -- 6 V Supply Current VCC=VTH +1V TS3809/3810CXA TS3809/3810CXB ICC -4.54 4.29 25 4.63 4.38 35 4.71 4.46 uA 3.92 3.02 4.00 3.08 4.08 3.15 TS3809/3810CXE TS3809/3810CXF 2.87 2.57 2.93 2.63 3.00 2.69 TS3809/3810CXG 2.20 2.25 2.30 Reset Threshold Reset Threshold Temperature Coefficient Set-up Time VCC to Reset Delay TS3809/3810CXC TS3809/3810CXD VTH V o TA=0~+85ºC VTHT -- 50 -- ppm/ C VCC = 0 ~ (VTH - 100mV) VCC = VTH ~ (VTH - 100mV) TSET TRD 1 -- -20 --- µS µS TDELAY 140 200 260 mS VOL -- -- 0.3 V VCC > VTH(MAX), ISOURCE =500µA VOH 0.8 VCC -- -- V VCC > VTH(MAX), ISINK =1.2mA VOL -- -- 0.3 V (RESET) Output (TS810) Voltage High 1.8V<VCC<VTH(MAX), ISOURCE =500µA 1.2V<VCC<1.8V, ISOURCE =150µA VOH 0.8 VCC -- -- V Hysteresis at Vcc Input Voltage VHVS -- 40 -- mV Reset Active Timeout Period RESET Output (TS809) Voltage Low RESET Output (TS809) Voltage High (RESET) Output (TS810) Voltage Low TA=0~+85ºC 1.8V<VCC<VTH(MAX), ISINK =1.2mA 1.2V<VCC<1.8V, ISINK =50µA 2/7 Version: C07 TS3809/3810 Series Microprocessor Reset Circuit Block Diagram Marking Information Part No. Identification Code Part No. Identification Code TS3809CXA CA TS3810CXA CH TS3809CXB CB TS3810CXB CI TS3809CXC CC TS3810CXC CJ TS3809CXD CD TS3810CXD CK TS3809CXE CE TS3810CXE CL TS3809CXF CF TS3810CXF CM TS3809CXG CG TS3810CXG CN 3/7 Version: C07 TS3809/3810 Series Microprocessor Reset Circuit Application Information Negative-Going VCC transients in addition to issuing a reset to the µP during power-up, power-down, and brownout conditions, the TS3809/3810 are relatively immune to short-duration negative-going Vcc transients (glitches). The TS3809/3810 do not generate a reset pulse. The graph was generated using a negative going pulse applied to Vcc, starting 0.5V above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph indicates the maximum pulse width a negative going Vcc transient can have without causing a reset pulse. As the magnitude of the transient increases (goes farther below the reset threshold), the maximum allowable pulse width decreases. Typically, a Vcc transient that goes 100mV below the reset threshold and lasts 20µS or less will not cause a reset pulse. A 0.1µF bypass capacitor mounted as close as possible to the Vcc pin provides additional transient immunity. Function Description A microprocessor’s (µP’s) reset input starts the µP In a know state. The TS3809/3810 assert reset to prevent codeexecution errors during power-up, power-down, or brownout conditions. They assert a reset signal whenever the Vcc supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after Vcc has risen above the reset threshold. The TS3809/3810 have a push-pull output stage. Ensuring a Valid Reset Output Down to Vcc=0 RESET is guaranteed to be a logic low for VCC > 1.0V. Once VCC exceeds the reset threshold, an internal timer keeps RESET low for the reset timeout period; after this interval, RESET goes high. If a brownout condition occurs (VCC dips below the reset threshold), RESET goes low. Any time VCC goes below the reset threshold, the internal timer resets to zero, and RESET goes low. The internal timer starts after VCC returns above the reset threshold, and RESET remains low for the reset timeout period. When Vcc falls below 1V, the TS3809/3810 reset output no longer sinks current - it becomes an open circuit. Therefore, high impedance CMOS logic input connected to reset can drift to undetermined voltages. This present no problem in most applications since most µP and other circuitry is inoperative with Vcc below 1V.However, in applications where reset must be valid down to 0V, adding a pull down resistor to reset causes and stray leakage currents to flow to ground, holding reset low (Figure 2.) R1’s value is not critical; 100K is large enough not to load reset and small enough to pull RESET to ground. For the TS3809/3810 if reset is required to remain valid for Vcc<1V. Benefits of Highly Accurate Reset Threshold Most µP supervisor ICs has reset threshold voltages between 5% and 10% below the value of nominal supply voltages. This ensures a reset will not occur within 5% of the nominal supply, but will occur when the supply is 10% below nominal. When using ICs rated at only the nominal supply ±5%, this leaves a zone of uncertainty where the supply is between 5% and 10% low, and where the reset many or may not be asserted Timming Diagram 4/7 Version: C07 TS3809/3810 Series Microprocessor Reset Circuit Electrical Characteristics Curve Figure 1. Threshold Voltage vs. Temperature Figure 2. TDELAY vs. Temperature Figure 3. Supply Current vs. Temperature Figure 4. Supply Current vs. Threshold Voltage Figure 5. Power-Down TDELAY vs. Temperature Figure 6. Output Voltage vs. Output Current 5/7 Version: C07 TS3809/3810 Series Microprocessor Reset Circuit SOT-23 Mechanical Drawing DIM A A1 B C D E F G H I J 6/7 SOT-23 DIMENSION MILLIMETERS INCHES MIN MAX MIN MAX. 0.95 BSC 0.037 BSC 1.9 BSC 0.074 BSC 2.60 3.00 0.102 0.118 1.40 1.70 0.055 0.067 2.80 3.10 0.110 0.122 1.00 1.30 0.039 0.051 0.00 0.10 0.000 0.004 0.35 0.50 0.014 0.020 0.10 0.20 0.004 0.008 0.30 0.60 0.012 0.024 5º 10º 5º 10º Version: C07 TS3809/3810 Series Microprocessor Reset Circuit Notice Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. Information contained herein is intended to provide a product description only. No license, express or implied, to any intellectual property rights is granted by this document. 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