TS810R

TS809/810/809R/810R Series Microprocessor Reset Circuit SOT-23 Pin Definition: TS809/TS810 1. Ground 2. RESET(RESET ) 3 . Vc c TS809R/TS810R 1. RESET(RESET ) 2. Ground 3 . Vc c General Description The TS809/810 series are microprocessor (µP) supervisory circuit used to monitor the pow er supplies in µP 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 power ed circuits . These circuits perfor m a single func tion: they assert a reset s ignal whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for at leas t 140ms after VCC has risen above the reset threshold. Reset thresholds suitable for operation with a v ariety of supply voltages are available. The TS809/810 series have push pull outputs. The TS809/809R have an ac tive low RESE T output, w hile the TS810/810R has an active high (R ESET) output. The reset comparator is designed to ignore fast transients on VCC, and the output guaranteed to be in the correc t logic state for VCC dow n to 1V. Low supply correct makes the TS809/810 series ideal for use in portable equipment. Features ● ● ● ● ● ● ● ● ● ● ● Highly Accurate: ±2% Precision monitoring of +3V, +3.3V and +5V power supply voltage Fully specified over temperature Available in three output configurations Push- Pull R ESET low output (TS809/TS809R) Push- Pull (R ESET) high output (TS810/TS810R) 140mS min. power-on reset pulse width 12uA supply current Guaranteed reset valid to Vcc = +1V Power supply trans ient immunity No external components Ordering Information Part No. Package Packi ng TS809C Xx R F SOT-23 3Kpcs / 7” Reel 3Kpcs / 7” Reel TS810C Xx R F SOT-23 3Kpcs / 7” Reel TS809RC Xx RF SOT-23 3Kpcs / 7” Reel TS810RC Xx 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 : 2.32V H : 2.1V I : 2.0V Applications ● ● ● ● ● ● Battery-operated systems Controllers Intelligent ins truments Critical uP and uC power monitor ing Portable / Battery powered equipment Automotive Application Circuit Pin Descriptions Name Gn d RESET (RESET) Vcc Descripti on Gr o u n d RESET – TS809 / TS809R ( Active Low) (RESET) – TS810 / TS810R (Ac tive High) Operating voltage input 1/7 Version: A07 TS809/810/809R/810R Series Microprocessor Reset Circuit Absolute Maximum Rating Parameter Terminal Voltage (with respec t to Gnd) RESET & (R ESET) push-pull Input Current, VCC Output Current, R ESET, (RESET) Rate of Rise, VCC Continuous Pow er Dissipation Operating Junction Temperature R ange Storage Temperature Range Lead Soldering Temperature (260 C) o Symbol VCC VRESET ICC IO VR PD TOPR TSTG TLEAD Maxi mum 7 - 0.3 ~ (VCC +0.3) 20 20 100 320 - 4 0 ~ +1 2 5 - 6 5 ~ +1 5 0 10 Unit V V mA mA V/uS mW o o C C S Electrical Specifications (Ta = 25oC, unless otherwise noted) Parameter Input Supply Voltage Supply Current o Conditi ons Ta=-40 C ~+85 C VIN=VIN *1.10 VIN=VIN *1.10, Ta=-40 C ~+85 C TS809/809R/810/810RC XA TS809/809R/810/810RC XB TS809/809R/810/810RC XC TS809/809R/810/810RC XD o o o Symbol VCC ICC Mi n 1.0 -4.56 4.31 3.94 3.03 Ty p ---4.63 4.38 4.00 3.08 2.93 2.63 2.32 2.1 2.0 50 40 210 -- Max 5.5 3.0 5.0 4.7 4.45 4.06 3.13 2.97 2.67 2.35 2.13 2.03 160 -500 0.2 Unit V uA Reset Threshold TS809/809R/810/810RC XE TS809/809R/810/810RC XF TS809/809R/810/810RC XG TS809C XH TS809C XI VTH 2.89 2.59 2.28 2.07 1.97 30 V Reset Threshold Temperatur e Coefficient VCC to Reset D elay Reset Ac tive Timeout Per iod RESET Output (TS809/R) Voltage Low RESET Output (TS809/R) Voltage High (RESET) Output (TS810/R) Voltage Low (RESET) Output (TS810/R) Voltage High VCC = VTH - 100mV o o Ta=-40 C ~+85 C VCC < VTH(MAX), ISINK =1.2mA VCC > VTH(MAX), ISOURCE =0.5mA, VCC > 1.8V VCC > VTH(MAX), ISOURCE =0.15mA, 1.8V ≥ VCC >1.0V VCC > VTH(MAX), ISINK =1.2mA VCC < VTH(MAX), ISOURCE =0.5mA, VCC > 1.8V VCC > VTH(MAX), ISOURCE =0.15mA, 1.8V ≥ VCC >1.0V TDELAY VOL ppm / o C uS mS V -140 -- VOH 0.8 VCC -- -- V VOL -- -- 0.2 V VOH 0.8 VCC -- -- V 2/7 Version: A07 TS809/810/809R/810R Series Microprocessor Reset Circuit Application Note Function Description A microprocessor’s (µP’s) reset input star ts the µP In a know s tate. The TS809/810/809R/810R assert reset to prevent code-execution errors during power-up, pow er-down, or brow nout conditions . They asser t 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 TS809/810/809R/810R have a push-pull output stage. Applicati ons Informati on Negative- Going VCC transients in addition to issuing a reset to the µP during pow er-up, power-down, and br ownout conditions, the TS809/810 are relatively immune to short-duration negative-going Vcc transients (glitches). The TS809/810/809R/810R do not generate a reset pulse. The graph w as generated using a negative going pulse applied to Vcc, s tarting 0.5V above the ac tual reset thr eshold and ending below it by the magnitude indicated (reset comparator overdrive) . The graph indicates the maximum pulse w idth a negative going Vcc transient can have without causing a reset pulse. As the magnitude of the transient increases (goes far ther below the reset threshold), the maximum allowable pulse w idth decreases. Typically, a Vcc transient that goes 100mV below the reset thr eshold and lasts 20µ S or less will not cause a reset pulse. A 0.1µF bypass capacitor mounted as close as possible to the Vcc pin prov ides additional transient immunity . Ensuri ng a Valid Reset Output Down to Vcc=0 When Vcc falls below 1V, the TS809/810/809R/810R 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 mos t µ P and other circuitry is inoperative w ith Vcc below 1V.However , in applications where reset must be valid down to 0V, adding a pull dow n resis tor to reset causes and stray leakage currents to flow to ground, holding r eset low (Figure 2.) R1’s value is not critical; 100K is large enough not to load reset and small enough to pull R ESET to ground. For the TS809/810/809R /810R if reset is required to remain valid for Vcc