RT9802 Preliminary User Programmable Micro-Power Voltage Detectors General Description Features The RT9802 is a micro-power voltage detector supervising the power supply voltage level for microprocessors (µP) or digital systems. It provides user programmable threshold levels with 0.1V step ranging from 1.5V to 5V, which covers most digital applications. It features low supply current of 3µA. Selection of VTH is easily achieved through 3 pins connected to GND, VDD or floating for different threshold voltage settings. Two versions of threshold voltages, 1.5V ~ 4V and 2.5V ~ 5V, which are programmed in factory are offered by customer demands. z z z z z z Applications z z z z The RT9802 performs supervisory function by sending out a reset signal whenever the VDD voltage falls below a preset threshold level. This reset signal will last the whole period before VDD recovering. Reset signal will release after VDD is recovered and lasts for the whole period of Reset Active Time-out period. User Programmable Threshold 1.5V to 5V in 0.1V Step with ±3% Accuracy Low Supply Current 3µA Quick Reset within 20µS Built-in Recovery Delay 200mS Low Functional Supply Voltage 0.9V Small SOT-26 Package z Computers Controllers Intelligent Instruments Critical µP and µC Power Monitoring Portable/Battery-Powered Equipment Pin Configurations Part Number RT9802 CE (Plastic SOT-26) RT9802 is CMOS, active-low output and provided in SOT-26 package. Pin Configurations TOP VIEW 6 5 4 1 2 3 1. 2. 3. 4. 5. 6. VSET0 GND RESET VDD VSET2 VSET1 Ordering Information RT9802 Typical Application Circuit Package Type E : SOT-26 Operating temperature range C: Commercial standard Reset Threshold A : 2.5V~5V B : 1.5V~4V VSET0 VSET1 µP GND RT9802 GND VSET2 VDD RESET RESET VDD RT9802B VTH = 2.5V in this example DS9802-00 January 2002 www.richtek.com 1 RT9802 Preliminary Pin Description Pin Name Pin Function VSET0 Threshold Voltage Selection Pin 1 GND Ground Pin RESET Reset Pulse Output, Negative Pulse VDD Power Pin VSET1 Threshold Voltage Selection Pin 2 VSET2 Threshold Voltage Selection Pin 3 Function Block Diagram Internal Clock VDD VDD P VSET0 VSET1 VSET CMP TIMER RESET N VSET2 Threshold Voltage Setting POR Power On Reset www.richtek.com 2 DS9802-00 January 2002 RT9802 Preliminary Absolute Maximum Ratings z z z z z z z Terminal Voltage (with Respect to GND) VDD All Other Inputs Input Current, VDD Continuous Power Dissipation, PD @ TA = 25°C SOT-26 Operating Junction Temperature Range Storage Temperature Range Package Thermal Resistance SOT-26, θJA Lead Temperature (Soldering, 5sec.) -0.3V to 6.0V -0.3V to VDD+0.3V 20mA 0.25W -40°C ~ 125°C -65°C ~ 125°C 250°C /W 260°C Electrical Characteristics (VDD = 3.0, unless specified) Parameter Symbol Test Conditions Min Typ Max Units 0.9 -- 6 V Operating VDD (VOUT) Range VDD Supply Current IDD VDD = 1.5V ~ 3.5V, IOUT = 0 VDD = 3.5V ~ 5V, IOUT = 0 -- Reset Threshold VTH TA = 27°C -- Threshold Voltage Accuracy ∆VTH TA = 27°C -- VCC Drop to Reset Delay tRD Drop = -125mV -- Reset Active Time Out Period tRP VDD ≥ 1.02×VTH, Programmable VIL DS9802-00 January 2002 3.3 Note1 µA -- V 3 % -- 20 µS -- 200 -- mS TA = 27°C -- 0.2VDD -- VIH TA = 27°C -- 0.85VDD -- VOL VDD < VTH, ISINK = 3.5mA -- 0.4 -- VSET Pin Input Threshold RESET Output Voltage 3 V V www.richtek.com 3 RT9802 Preliminary Note 1: Pin Conditions for Programmable Threshold Voltage Setting RT9802A RT9802B VSET0 input VSET1 input VSET2 input 5 4 VDD VDD VDD 4.9 3.9 VDD VDD floating 4.8 3.8 VDD VDD GND 4.7 3.7 VDD floating VDD 4.6 3.6 VDD floating floating 4.5 3.5 VDD floating GND 4.4 3.4 VDD GND VDD 4.3 3.3 VDD GND floating 4.2 3.2 VDD GND GND 4.1 3.1 floating VDD VDD 4 3 floating VDD floating 3.9 2.9 floating VDD GND 3.8 2.8 floating floating VDD 3.7 2.7 floating floating floating 3.6 2.6 floating floating GND 3.5 2.5 floating GND VDD 3.4 2.4 floating GND floating 3.3 2.3 floating GND GND 3.2 2.2 GND VDD VDD 3.1 2.1 GND VDD floating 3 2 GND VDD GND 2.9 1.9 GND floating VDD 2.8 1.8 GND floating floating 2.7 1.7 GND floating GND 2.6 1.6 GND GND VDD 2.5 1.5 GND GND floating VDD: bond to VDD; 0: bond to GND; f: no bonding www.richtek.com 4 DS9802-00 January 2002 RT9802 Preliminary Package Information D C B b H A A1 e Symbol L Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.889 1.295 0.035 0.051 A1 -- 0.152 -- 0.006 B 1.397 1.803 0.055 0.071 b 0.356 0.559 0.014 0.022 C 2.591 2.997 0.102 0.118 D 2.692 3.099 0.106 0.122 e 0.838 1.041 0.033 0.041 H 0.102 0.254 0.004 0.010 L 0.356 0.610 0.014 0.024 SOT- 26 Surface Mount Package DS9802-00 January 2002 www.richtek.com 5 RT9802 Preliminary RICHTEK TECHNOLOGY CORP. RICHTEK TECHNOLOGY CORP. Headquarter Taipei Office (Marketing) 5F, No. 20, Taiyuen Street, Chupei City 8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City Hsinchu, Taiwan, R.O.C. Taipei County, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Tel: (8862)89191466 Fax: (8862)89191465 Email: [email protected] www.richtek.com 6 DS9802-00 January 2002