RT9828 Dual Micro-Power Voltage Detectors General Description Features The RT9828 is a micro-power voltage detector supervising the power supply voltage level for microprocessors (uP) or digital systems. It provides internally fixed threshold levels ranging from 1.2V to 5V, which covers most digital applications. It features low supply current of 6uA. The RT9828 performs supervisory function by sending out a reset signal whenever the VDD voltage falls below a preset z threshold level. This reset signal will last the whole period before VDD recovering. Once the VDD exceeds the threshold level, the reset signal will be released after a certain delay time. The RT9828 is available in SOT-23-6 package. z z z z z z z RT9828 - z z z Package Type E : SOT-23-6 Lead Plating System P : Pb Free G : Green (Halogen Free and Pb Free) Threshold Voltage : RESET1/RESET2 WP : 1.6V/3.0V GP : 1.8V/3.0V Low Supply Current 6uA Quick Reset within 20us Built-in 55ms Recovery Delay Low Functional Supply Voltage 0.9V Dual N-Channel Open-Drain Output Small SOT-23-6 Packages RoHS Compliant and 100% Lead (Pb)-Free Applications z Ordering Information High Accuracy ±1.5% z Computers Controllers Intelligent Instruments Critical uP and uC Power Monitoring Portable/Battery-Powered Equipment Pin Configurations (TOP VIEW) RESET1 GND VDD2 6 5 4 2 3 Note : Richtek products are : ` RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. ` VDD1 NC RESET2 SOT-23-6 Suitable for use in SnPb or Pb-free soldering processes. Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. DS9828-02 April 2011 www.richtek.com 1 RT9828 Typical Application Circuit 100k RT9828 V DD1 1 VDD1 RESET1 GND V DD2 4 VDD2 RESET2 6 RESET1 5 3 RESET2 100k Functional Pin Description Pin No. Pin Name Pin Function 1 VDD1 Input of Detector1. 2 NC No Internal Connection. It should be floating. 3 RESET2 Active Low Open-Drain Reset Pin of Detector2. 4 VDD2 Input of Detector2. 5 GND Ground. 6 RESET1 Active Low Open-Drain Reset Pin of Detector1. Function Block Diagram RESET1 VDD1 VSET1 Timer CMP N MOS GND Threshold Voltage Setting POR Power On Reset RESET2 VDD2 VSET2 Timer CMP N MOS Threshold Voltage Setting POR Power On Reset Available Voltage Version Code C B F W G D Y H E J K Voltage 1.2 1.3 1.5 1.6 1.8 1.85 1.9 2 2.1 2.5 2.6 Code T L M N V P Q R S T -- Voltage 2.65 2.7 2.8 2.85 2.9 3 3.1 3.2 3.3 5 -- www.richtek.com 2 DS9828-02 April 2011 RT9828 Absolute Maximum Ratings z z z z z z z z z (Note 1) Input Voltage (with Respect to GND) VDD1/VDD2 --------------------------------------------------------------------------------------------------------------- −0.3V to 6V All Other Inputs -------------------------------------------------------------------------------------------------------- −0.3V to VDD + 0.3V Input Current, IDD1/IDD2 ----------------------------------------------------------------------------------------------- 20mA Power Dissipation, PD @ TA = 25°C SOT-23-6 ---------------------------------------------------------------------------------------------------------------- 0.4W Package Thermal Resistance (Note 2) SOT-23-6, θJA ----------------------------------------------------------------------------------------------------------- 250°C/W Lead Temperature (Soldering, 10sec.) ---------------------------------------------------------------------------- 260°C Junction Temperature ------------------------------------------------------------------------------------------------- 150°C Storage Temperature Range ---------------------------------------------------------------------------------------- −65°C to 150°C ESD Susceptibility (Note 3) HBM (Human Body Mode) ------------------------------------------------------------------------------------------ 2kV MM (Machine Mode) -------------------------------------------------------------------------------------------------- 200V Recommended Operating Conditions z z (Note 4) Junction Temperature Range ---------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range ---------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VDD = 3V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max 0.9 -- 6 V -- 6 16 uA −1.5 -- +1.5 % Drop = V TH −125mV -- 20 -- us VDD ≥ 1.02 × VTH -- 55 -- ms 1.6 = V DD < VTH , ISINK > 3.5mA -- -- 0.4 V -- 0.01VTH -- V Input Voltage VDD1 / VDD2 Supply Current IVDD1 / IVDD2 VTH = 3V, VDD = 4.5V Threshold Voltage Accuracy ΔVTH V DD Drop to Reset Delay tRD Reset Active Time Out Period tRP RESET Output Voltage Low VOL Hysteresis Width VHYS Units Note 1. Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. θJA is measured in the natural convection at TA = 25°C on a low effective single layer thermal conductivity test board of JEDEC 51-3 thermal measurement standard. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. DS9828-02 April 2011 www.richtek.com 3 RT9828 Typical Operating Characteristics Nch Driver Sink Current vs. Input Voltage VTH = 1.6V, VDS = 0.5V VTH = 3V, VDS = 0.5V -30°C 35 30 Nch Driver Sink Current (mA) Nch Driver Sink Current (mA) Nch Diver Sink Current vs. Input Voltage 20 40 25°C 25 20 80°C 15 10 5 16 -30°C 25°C 12 8 80°C 4 0 0 0 0.5 1 1.5 2 2.5 3 0 3.5 0.4 0.8 1.2 1.6 2 Input Voltage (V) Input Voltage (V) VDD1 Supply Current vs. Input Voltage VDD2 Supply Current vs. Input Voltage 5 5 VTH = 1.6V VTH = 3V 80°C 4 25°C Supply Current (uA) Supply Current (uA) 4 3 -30°C 2 1 2 -30°C 1 0 0 0 1 2 3 4 5 0 6 1 2 3 4 5 6 Input Voltage (V) Input Voltage (V) Output Voltage vs. Input Voltage Output Voltage vs. Input Voltage 6 6 VTH = 3V VTH = 1.6V 5 5 Output Voltage (V) Output Voltage (V) 80°C 25°C 3 4 3 2 1 4 3 2 1 0 0 0 1 2 3 4 Input Voltage (V) www.richtek.com 4 5 6 0 1 2 3 4 5 6 Input Voltage (V) DS9828-02 April 2011 RT9828 Power-Up Reset Time-Out vs. Temperature Reset Threshold Deviation vs. Temperature 100 Reset Threshold (V) VTH = 3V 3.0 2.5 2.0 VTH = 1.6V Power-Up Reset Time-Out (ms) 3.5 80 VTH = 1.6V 60 VTH = 3V 40 20 0 1.5 -50 -25 0 25 50 75 100 -50 125 -25 0 Power-Down Reset Time-Out vs. Temperature VDROP = 200mV VDROP = 150mV VDROP = 250mV 4 0 -50 -25 0 25 50 75 Temperature (°C) DS9828-02 April 2011 100 125 Power-Down Reset Time-Out (us) Power-Down Reset Time-Out (us) 16 8 75 100 125 Power-Down Reset Time-Out vs. Temperature 40 VTH = 1.6V 12 50 Temperature (°C) Temperature (°C) 20 25 VTH = 3V 35 30 VDROP = 200mV 25 VDROP = 150mV 20 VDROP = 250mV 15 10 -50 -25 0 25 50 75 100 125 Temperature (°C) www.richtek.com 5 RT9828 Application Information The RT9828 voltage detector monitors the input voltage fo generate a reset signal while the input voltage is lower then the detecting threshold voltage level. The RESET pin is an open drain output. It is recommended to connect a pull-up resister between RESET pin and VIN. Figure 1 shows the timming diagram of VDD and RESET signals. When VDD is lower than VTH, the RESET goes low after a short delay time tRD. When VDD is higher than VTH with a hystersis (VHYS), the RESET will be pulled up after the delay time tRP. The typical value of the delay time tRD and tRP are showed in specification. packages, the thermal resistance θJA is 250°C/W on the standard JEDEC 51-3 single layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by following formula : PD(MAX) = (125°C − 25°C) / (250°C/W) = 0.400W for SOT-23-6 packages The maximum power dissipation depends on operating ambient temperature for fixed TJ(MAX) and thermal resistance θJA. For RT9828 packages, the Figure 2 of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. VDD V TH + V HYS V TH Minimum operation voltage RESET tRP tRD Figure 1. Timming Diagram Maximum Power Dissipation (W) 0.50 Single Layer PCB 0.45 0.40 0.35 SOT-23-6 0.30 0.25 0.20 0.15 0.10 0.05 0.00 0 25 50 75 100 125 Ambient Temperature (°C) Thermal Considerations Figure 2. Derating Curves for RT9828 Packages For continuous operation, do not exceed absolute maximum operation junction temperature. The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference between junction to ambient. The maximum power dissipation can be calculated by following formula : PD(MAX) = ( TJ(MAX) − TA ) / θJA Where T J(MAX) is the maximum operation junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. For recommended operating conditions specification of RT9828, where T J(MAX) is the maximum junction temperature of the die (125°C) and TA is the maximum ambient temperature. The junction to ambient thermal resistance θ JA is layout dependent. For SOT-23-6 www.richtek.com 6 DS9828-02 April 2011 RT9828 Outline Dimension H D L C B b A A1 e Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.889 1.295 0.031 0.051 A1 0.000 0.152 0.000 0.006 B 1.397 1.803 0.055 0.071 b 0.250 0.560 0.010 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 0.080 0.254 0.003 0.010 L 0.300 0.610 0.012 0.024 SOT-23-6 Surface Mount Package Richtek Technology Corporation Richtek Technology Corporation Headquarter Taipei Office (Marketing) 5F, No. 20, Taiyuen Street, Chupei City 5F, No. 95, Minchiuan Road, Hsintien City Hsinchu, Taiwan, R.O.C. Taipei County, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Tel: (8862)86672399 Fax: (8862)86672377 Email: [email protected] Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be guaranteed by users when integrating Richtek products into any application. No legal responsibility for any said applications is assumed by Richtek. DS9828-02 April 2011 www.richtek.com 7