UNISONIC TECHNOLOGIES CO., LTD UIC809 CMOS IC MICROPROCESSOR RESET CIRCUITS DESCRIPTION The UTC UIC809 series are resetting circuits which can monitor power supplies especially in microprocessor based systems. In normal operation, the UTC UIC809 series can assert a reset under any of the following situation: the power supply drops below a designated reset threshold level (which is available for 3V or 3.3V or 5V system) is forced low. There is an internal active low RESET output which has already been guaranteed to remain asserted for at 140ms least while VCC rises above the designed threshold level. FEATURES * Voltage monitor for 3V or 3.3V or 5V power supplies * Valid RESET remains with VCC as low as 1V * Typical supply current: 5µA * Fixed 140ms minimum reset pulse width * With Manual reset input ORDERING INFORMATION Ordering Number Package UIC809G-x-AE2-3-R SOT-23-3 Note: Pin Assignment : 1 Pin Assignment 2 3 RESET GND VCC Packing Tape Reel x: Output Voltage, refer to Marking Information. www.unisonic.com.tw Copyright © 2014 Unisonic Technologies Co., Ltd 1 of 8 QW-R119-024.A UIC809 CMOS IC MARKING INFORMATION PACKAGE VOLTAGE CODE SOT-23-3 B : 2.93V PIN CONFIGURATION PIN DESCRIPTION No. PIN NAME 1 RESET 2 3 GND VCC MARKING DESCRIPTION This pin will fall low after the VCC’s falling below the reset threshold voltage and it also can remain asserted for at least 140ms min after VCC’s rising upon the reset threshold. Ground Input of power supply. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 8 QW-R119-024.A UIC809 CMOS IC BLOCK DIAGRAM FUNCTIONAL DIAGRAM VCC VTH tRST RESET Reset Timing Diagram UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 8 QW-R119-024.A UIC809 CMOS IC ABSOLUTE MAXIMUM RATING PARAMETER Input Voltage Input Current (VCC) SYMBOL VCC IIN RATINGS -0.3~+6.0 20 UNIT V mA IOUT 20 mA Output Current ( RESET ) Rate of Rise VCC(RR) 100 V/µs Power Dissipation (TA =+70°C) PD 300 mW Operating Temperature TOPR -40~+125 °C Storage Temperature TSTG -65~+150 °C Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. 2. The device is not guaranteed to function outside its operating rating. ELECTRICAL CHARACTERISTICS UIC809-B (2.93V) (VCC =3.3V, TA= 25°C, unless otherwise specified) PARAMETER Operating Voltage Range Supply Current Reset Voltage Threshold Reset Timeout Period Reset Output Voltage SYMBOL TEST CONDITIONS VCC TA =-40~+85°C ICC VCC=3.3V, no load VTH tRST VOH ISOURCE =500µA VCC = VTH min, ISINK =1.2mA VOL VCC>1V, ISINK =50µA, TA =-40~+85°C UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 1 2.85 140 2.64 TYP MAX UNIT 6 V 5 10 µA 2.93 3.00 V 240 560 ms V 0.3 V 0.3 V 4 of 8 QW-R119-024.A UNISONIC TECHNOLOGIES CO., LTD UIC809 CMOS IC TYPICAL APPLICATION CIRCUIT VCC VCC VCC UTC UIC809 µP RESET RESET APPLICATION INFORMATION Microprocessor Reset As soon as VCC falls below the reset threshold voltage, the RESET pin is asserted. But the RESET pin can keep asserted for a period of 140ms after VCC rose above the reset threshold voltage. After a power failure the reset operation can keep the processor being reset and powers up properly. VCC Transients The UTC UIC809 series won’t cause a reset typically as this situation: a negative-going transient 125mV below the reset threshold with a duration of 20µs or less. Interfacing to Bidirectional Reset Pins Connecting a 4.7kΩ resistor in series with the UTC UIC809 series output and the µP reset pin can make the UTC UIC809 series interface with µPs with bidirectional reset pins. RESET Valid at Low Voltage As the figure below, adding a resistor which is recommended 100kΩ can ensure the RESET output remains low with VCC down to 0V. The size of the resistor should be not too large which will load the output excessively and not too small which can pull-down any stray leakage currents. www.unisonic.com.tw Copyright © 2014 Unisonic Technologies Co., Ltd 5 of 8 QW-R119-024.A UIC809 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw CMOS IC 6 of 8 QW-R119-024.A UIC809 CMOS IC TYPICAL CHARACTERISTICS Reset Timeout out Period CH1：VCC CH2：Reset UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 8 QW-R119-024.A UIC809 CMOS IC UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 8 of 8 QW-R119-024.A