CYT 809 Microprocessor Reset Monitoror(Preliminary) General Description Features Precision VCC Monitor for 3.0V, 3.3V, and 5.0V Supplies ■ 140msec Guaranteed Minimum RESET Output Duration ■ RESET Output Guaranteed to VCC=1.0V ■ Low 15µA Supply Current ■ VCC Transient Immunity ■ Small SOT-23 Package ■ No External Components The CYT809 is a cost-effective system supervisor circuits designed to monitor VCC in digital systems and provide a reset signal to the host processor when necessary. No external components are required. The reset output is driven active within 20µsec of VCC falling through the reset voltage threshold.Reset is maintained active for a minimum of140msec after VCC rises above the reset threshold.The CYT809 has an active-low RESET output. The output of the CYT809 is guaranteed valid down to VCC=1V. Both devices are available in a SOT-23 package. The CYT809 is optimized to reject fast transient glitches on the VCC line. Low supply current of 15µA (VCC=3.3V) makes these devices suitable for batterypowered applications. ■ Applications ■ ■ ■ ■ Computers Embedded systems Battery powered equipment Critical µP power supply monitoring SOT-23 Package ShenZhen CYT IC Design CO ,Ltd 1 CYT 809 Pin Configuration Typical Application Ordering/Marking Information CYT809- X X Yield periods: A-Z : 1-26 a-z : 27-52 Output Voltage: L : 4.63V M : 4.38V J : 4.00V T : 3.08V S : 2.93V R : 2.63V ShenZhen CYT IC Design CO ,Ltd 2 CYT 809 PIN DESCRIPTION: Pin No. Symbol Description 1 GND Ground 2 RESET RESET output remains low while Vcc is below the reset voltage threshold and for 240msec(typ) after Vcc rises above reset threshold 3 VCC Supply Voltage(typ.) Operating Rating (1) Parameter Symbol Value Units Supply Input Voltage VCC +2.0V to +5.5 V Junction Temperature TJ 0 to +125 °C Absolute Maximum Rating (2) Parameter Symbol Value Units Input Voltage VCC +5.5 V Output Voltage RESET -0.3 to (Vcc+0.3) V Input current -- 20 mA Output Current IOUT 20 Power Dissipation PD Internally Limited Output Short Circuit Duration mA (3) Infinite Thermal Resistance, Junction-to-Ambient ΘJA 230 °C/W Operating Temperature Range TA 0-85 °C 260 °C Lead Temperature (Soldering, 10 sec.) Junction Temperature TJ 0 to +125 °C Storage Temperature TS -65 to +150 °C ShenZhen CYT IC Design CO ,Ltd 3 CYT 809 Electrical Characteristics VIN = VEN = 3.6V; TJ = 25°C; unless otherwise specified Symbol VCC Parameter Input Voltage Range ICC Supply Current VTH Reset Threshold Conditions CYT809LXX: CYT809MXX: CYT809JXX: CYT809TXX: CYT809SXX: CYT809RXX: Reset Threshold Temperature Coefficient(4) Vcc to Reset Delay Vcc=VTH to (VTH-100mV) Reset Active Timeout Period Min 2.0 Typ -- Max 5.5 Unit V -- 18 25 uA 4.54 4.29 3.92 3.02 2.87 2.58 4.63 4.38 4.00 3.08 2.93 2.63 4.72 4.47 4.08 3.14 2.99 2.68 V -- 30 -- Ppm/°C -- 20 -- usec 140 240 600 msec VOL RESET Output Voltage Low ISNK=3mA -- -- 0.4 V VOH RESET Output Voltage High ISOURCE = 800uA 0.8Vcc -- -- V Note 1: Exceeding the absolute maximum rating may damage the device. Note 2: The device is not guaranteed to function outside its operating rating. Note 3: The maximum allowable power dissipation at any TA (ambient temperature) is calculated using: PD(MAX) = (TJ(MAX) – TA)/ΘJA. Exceeding the maximum allowable power dissipation will result in excessive die temperature,and the regulator will go into thermal shutdown. See “Thermal Consideration” section for details Note 4: RESET threshold temperature coefficient is the worst case voltage change divided by the total temperature range. ShenZhen CYT IC Design CO ,Ltd 4 CYT 809 Outline Drawing SOT-23 DIM N A A1 B C D H E e e1 L1 L Q DIMENSIONS INCHES MM MIN MAX MIN MAX 0.035 0.043 0.90 1.10 0.0004 0.005 0.01 0.13 0.012 0.020 0.30 0.50 0.004 0.008 0.09 0.20 0.110 0.122 2.80 3.10 0.098 0.122 2.50 3.10 0.059 0.067 1.50 1.70 0.037REF 0.95REF 0.075REF 1.90REF 0.008 0.022 0.20 0.55 0.014 0.031 0.35 0.80 0°C 10°C 0°C 10°C ShenZhen CYT IC Design CO ,Ltd 5