TS809CXF

TS809/ 810/ 809R/ 810R Microprocessor Reset Circuit Pin assignment: TS809/810 1. Gnd 2. RESET (RESET) 3. Vcc Pin assignment: TS809R/810R 1. RESET (RESET) 2. Gnd 3. Vcc Threshold Voltage Option From 2.63V ~ 4.63V General Description The TS809/810/809R/810R are microprocessor (µP) supervisory circuit used to monitor the power 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 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 240ms(typ) after VCC has risen above the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available. The TS809/810/809R/810R have push pull outputs. The TS809/809R have an active low RESET output, while the TS810/810R has an active high RESET output. The reset comparator is designed to ignore fast transients on VCC, and the output guaranteed to be in the correct logic state for VCC down to 1V. Low supply correct makes the TS809/810/809R/810R ideal for use in portable equipment. The TS809/810/809R/810R is available in a 3-pin SOT-23 package. Features 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 (TS809 & TS809R) Push-Pull RESET high output (TS810 & TS810R) 140mS min. power-on reset pulse width 12uA supply current Guaranteed reset valid to Vcc = +1V Power supply transient immunity No external components Ordering Information Part No. TS809CX x TS810CX x TS809RCXx TS810RCXx Enable Function Active-Low Active-High Active-Low Active-High Package 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 Applications Computers Controllers Intelligent instruments Critical uP and uC power monitoring Portable / Battery powered equipment Automotive Pin Descriptions Name Gnd Ground Reset output pin RESET (RESET) Vcc L: for TS809 & TS811 H: for TS809R & TS811R Operating voltage input Description TS809/810/809R/810R 1-6 2004/09 rev. D Absolute Maximum Rating Terminal Voltage (with respect to Gnd) RESET & (RESET) push-pull Input Current, Vcc Output Current, RESET, (RESET) Continuous Power Dissipation (Ta=+70 C) de-rate 4mW/ C above +70 C Operating Junction Temperature Range Storage Temperature Range Lead Soldering Temperature (260 C) o o o o VCC VRESET ICC IO PD - 0.3 ~ +6.0 - 0.3 ~ (VCC +0.3) 20 20 320 V V mA mA mW o o TOP TSTG TLEAD -40 ~ +105 -65 ~ +150 10 C C S Electrical Characteristics (Ta = 25 oC, unless otherwise specified.) Parameter Input Supply Voltage Supply Current o Conditions Ta = 0 C ~ +70 C VCC ≤ 5.5V VCC ≤ 3.6V TS809/910/809R/810RCXA TS809/910/809R/810RCXB o Symbol VCC ICC Min 1.0 -4.56 4.31 Typ -19 17 4.63 4.38 4.00 3.08 2.93 2.63 30 -20 Max 5.5 60 50 4.7 4.45 4.06 3.13 2.97 2.67 --100 600 0.3 Unit V uA Reset Threshold TS809/910/809R/810RCXC TS809/910/809R/810RCXD TS809/910/809R/810RCXE TS809/910/809R/810RCXF VTH 3.94 3.03 2.89 2.59 V Reset Threshold Temperature Coefficient Vcc Rising Time to Function VCC to Reset Delay Reset Active Timeout Period Ta = -20 C ~ +105 C VCC = VTH to (VTH - 100mV) Ta = 0 C ~ +70 C VCC = VTH(MIN), ISINK =1.2mA, RESET Output Voltage Low TS809 & TS809R VCC = VTH(MIN), ISINK =3.2mA, VCC > 1.0V, ISINK =50uA RESET Output Voltage High VCC > VTH(MAX), ISOURCE =500uA, TS809 & TS809R VCC > VTH(MAX), ISOURCE =800uA, RESET Output Voltage Low VCC = VTH(MAX), ISINK =1.2mA, TS810 & TS810R VCC = VTH(MAX), ISINK =3.2mA, RESET Output Voltage High 1.8V < VCC < VTH(MIN), ISOURCE =150uA, TS810 & TS810R o o o o VTH -25 ppm/ o C uS/V uS mS TDELAY 100 -VOL --0.8 VCC VOH VCC –1.5 -VOL -VOH 0.8 VCC 240 -- V ---0.4 0.3 -V ---0.3 V --0.4 -V TS809/810/809R/810R 2-6 2004/09 rev. D Application Note Function Description A microprocessor’s (µP’s) reset input starts the µP In a know state. The TS809/810/809R/810R assert reset to prevent code-execution 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 TS809/810/809R/810R have a push-pull output stage. Ensuring 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 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 TS809/810/809R/810R if RESET is required to remain valid for Vcc