RT9834. Micro-Power Voltage Detector with Manual Reset. Features. General Description. Applications. Marking Information

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1 RT98 Micro-Power Voltage Detector with Manual Reset General Description The RT98 is a micro-power voltage detector with deglitched manual reset input supervising the power supply voltage level for microprocessors (μp) or digital systems. It provides internally fixed threshold levels with.v per step ranging from.v to V, which covers most digital applications. It features low supply current of μa. The RT98 performs supervisory function by sending out a reset signal whenever the V DD voltage falls below a preset threshold level. This reset signal will last the whole period before V DD recovering. Once V DD recovered upcrossing the threshold level, the reset signal will be released after a certain delay time. To pull reset signal low manually, just pull the manual reset input (MR) below the specified V IL level. The RT98 is available in the SC-8 and SOT- packages. Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. Features Internally Fixed Threshold.V to V in.v Step High Accuracy ±.% Low Supply Current μa No External Components Required Quick Reset within μs Built-in Recovery Delay : ms, ms, ms, ms Options 8ns Glitch Immunity of Manual Reset Input Low Functional Supply Voltage.9V CMOS Push-Pull Output Small SC-8 and SOT- Packages RoHS Compliant and Halogen Free Applications Computers Controllers Intelligent Instruments Critical μp and μc Power Monitoring Portable/Battery-Powered Equipment Simplified Application Circuit VDD µp / RT98 VDD MR / GND Copyright Richtek Technology Corporation. All rights reserved. DS98- May

2 Ordering Information RT98 - Package Type H : SOT- Y : SC-8 Lead Plating System G : Green (Halogen Free and Pb Free) Threshold Voltage :.V :.V : 9 :.9V :.V Pin Configurations VDD MR GND / SOT- (TOP VIEW) VDD GND SC-8 MR / Reset Active Timeout Period A = ms () B = ms () C = ms () D = ms () E = ms () F = ms () G = ms () H = ms () Note : Richtek products are : RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-. Suitable for use in SnPb or Pb-free soldering processes. Functional Pin Description Pin No. Pin Name Pin Function GND Ground. Active Low Push-Pull Reset Output. Active High Push-Pull Reset Output. MR Manual Reset. VDD Power. Copyright Richtek Technology Corporation. All rights reserved. DS98- May

3 Function Block Diagram VDD MR VDD VSET Threshold Voltage Setting CMP POR Timer P MOS N MOS / Power On Reset Operation When VDD is lower than threshold voltage set by VSET circuit, the output becomes high. If VDD remains higher than the threshold voltage with a hysteresis voltage, Timer will be active. After a specific delay time, the output becomes low. There is an internal pull-high resistor connected to the MR pin. MR resets the RT98 only when it is pulled low. When MR releases and waits for a delay time, output returns to its normal state related to VDD. The pin is a Pull-Push output, and it will pull the output high to VDD, low to Ground. Adding a pullhigh resistor tied to any power which higher than VDD is forbidden. Timer The Timer provides four kinds of delay time options including ms, ms, ms, and ms. VSET The VSET generates a fixed threshold voltage. CMP Voltage Comparator which compares the voltage difference between threshold voltage and VDD. POR Power on reset. It will set all digital logic to the right state when power on. Copyright Richtek Technology Corporation. All rights reserved. DS98- May

4 Absolute Maximum Ratings (Note ) Terminal Voltage (with Respect to GND) V DD V to 6V All Other Inputs V to (V DD +.V) Input Current, I VDD ma Power Dissipation, P T A = C SOT W SC W Package Thermal Resistance (Note ) SOT-, θ JA C/W SC-8, θ JA C/W Lead Temperature (Soldering, sec.) C Storage Temperature Range C to C ESD Susceptibility (Note ) HBM (Human Body Model) kv Recommended Operating Conditions (Note ) Junction Temperature Range C to C Ambient Temperature Range C to 8 C Electrical Characteristics (V DD = V, T A = C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Operating V DD (V OUT ) Range V DD RT98A/B/C/D RT98E/F/G/H Supply Current I DD V TH = V, V DD =.V -- 8 μa Reset Threshold V TH --. to -- V Threshold Voltage Accuracy ΔV TH. --. % Threshold Voltage Hysteresis V HYS --. V TH -- V V DD Drop to Reset Delay t RD Drop = V TH mv μs Reset Active Timeout Period Output Voltage Low RT98A/E RT98B/F 7 t RP V DD. x V TH RT98C/G 97 RT98D/H 9 68 V OL V DD < V TH(MIN),I SINK =.ma, V TH V V DD < V TH(MIN),I SINK =.ma, V TH.8V V TH(MIN) > V DD > V, I SINK =.ma V ms V Copyright Richtek Technology Corporation. All rights reserved. DS98- May

5 Parameter Symbol Test Conditions Min Typ Max Unit Output Voltage High Output Voltage Low Output Voltage High MR Active Timeout Period V OH V OL V OH V DD > V TH(MAX), I SOURCE = 8μA, V TH V V DD > V TH(MAX), I SOURCE = μa, V TH.8V V DD > V TH(MAX), I SOURCE = μa, V TH.V V DD > V TH(MAX), I SINK =.ma, V TH V V DD > V TH(MAX), I SINK =.ma, V TH.8V V DD > V TH(MAX), I SINK =.ma, V TH.V.V < V DD < V TH(MIN), I SOURCE = μa.8v < V DD < V TH(MIN), I SOURCE = μa V < V DD < V TH(MIN), I SOURCE = 8μA V DD V DD V DD V DD V DD V DD RT98A/E RT98B/F 7 t MR RT98C/G 97 RT98D/H 9 68 MR Input Voltage Logic-High V MR_H V DD > V TH(MAX).7 x V DD -- V DD Threshold Logic-Low V MR_L V DD > V TH(MAX) x V DD Note. Stresses beyond those listed Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and 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 may affect device reliability. Note. θja is measured at TA = C on a high effective thermal conductivity four-layer test board per JEDEC -7. Note. Devices are ESD sensitive. Handling precaution is recommended. Note. The device is not guaranteed to function outside its operating conditions. V V V ms V Copyright Richtek Technology Corporation. All rights reserved. DS98- May

6 Typical Application Circuit VDD µp / RT98 VDD MR / GND Copyright Richtek Technology Corporation. All rights reserved. 6 DS98- May

7 Typical Operating Characteristics Nch Driver Output Current vs. V DS Nch Driver Output Current vs. V DS. RT98A- 6 RT98C-. VDD =.V VDD =.8V Output Current (ma) VDD = V Output Current (ma) VDD =.V VDD = V VDD =.V V DS (V) V DS (V) Nch Driver Output Current vs. V DS Output Voltage vs. Input Voltage RT98A- 7 RT98A 6 Output Current (ma) 8 6 VDD =.V = V =.V = V =.V = V =.V Output Voltage (V).9V V V 6 V DS (V) Supply Current vs. Input Voltage Supply Current vs. Input Voltage 6 RT98A- RT98C- Supply Current (µa) 8 C C C Supply Current IDD (µa) 8 C C C 6 6 Copyright Richtek Technology Corporation. All rights reserved. DS98- May 7

8 Supply Current vs. Input Voltage RT98A- Power-Down Reset Delay vs. Temperature RT98A- Supply Current (µa) 8 C C C Power-Down Reset Delay (µs) 9 6 VDROP = mv VDROP = mv VDROP = mv Power-Down Reset Delay (µs) Power-Down Reset Delay vs. Temperature RT98C- VDROP = mv VDROP = mv VDROP = mv Power-Down Reset Delay (µs) Power-Down Reset Delay vs. Temperature RT98A- VDROP = mv VDROP = mv VDROP = mv Sink Current I SINK (ma) Nch Driver Sink Current vs. Input Voltage RT98C-, VDS =.V C C 8 C Sink Current I SINK (ma) Nch Driver Sink Current vs. Input Voltage RT98A-, VDS =.V C C 8 C.... Copyright Richtek Technology Corporation. All rights reserved. 8 DS98- May

9 Reset Threshold Deviation (V) Reset Threshold Deviation vs. Temperature 6 RT98 V.V.V.V.V Output Current (ma) Pch Driver Output Current vs. Input Voltage RT98C- VDS =.V VDS =.V VDS = V VDS =.V 6 Power-Up Reset Timeout (ms) Power-Up Reset Timeout vs. Temperature RT98C VTH =.9V VTH = V Power-Up Reset Timeout (ms) 7 Power-Up Reset Timeout vs. Temperature RT98A VTH = V VTH =.V Output Delay Time (ms) Output Delay Time vs. Load Capacitance VTH = V. VTH =.9V VTH = V Load Capacitance (µf) Nch Driver Output Current (ma) Nch Driver Output Current vs. V DS RT98G- 6 V DS (V) VDD = 6V =.V = V =.V = V =.V Copyright Richtek Technology Corporation. All rights reserved. DS98- May 9

10 Nch Driver Output Current vs. Input Voltage Power-Up Reset Timeout vs. Temperature Nch Driver Output Current (ma) 6 RT98G- VDS =.V C C 8 C Power-Up Reset Timeout (ms) RT98G Output Voltage vs. Input Voltage Power-Down Reset Delay vs. Temperature 7 RT98G- RT98G- Output Voltage (V) 6 Power-Down Reset Delay (µs) VDROP = mv VDROP = mv VDROP = mv Copyright Richtek Technology Corporation. All rights reserved. DS98- May

11 Application Information Benefits of Highly Accurate Reset Threshold Most μp supervisor ICs have reset threshold voltages between % and.% below the value of nominal supply voltages. This ensures a reset will not occur within % of the nominal supply, but will occur when the supply is.% below nominal. Thermal Considerations For continuous operation, do not exceed absolute maximum junction temperature. The maximum power dissipation depends on the thermal resistance of the IC package, PCB layout, rate of surrounding airflow, and difference between junction and ambient temperature. The maximum power dissipation can be calculated by the following formula : Maximum Power Dissipation (W).6 Four-Layer PCB. SOT-.. SC Ambient Figure. Derating Curve of Maximum Power Dissipation P D(MAX) = (T J(MAX) T A ) / θ JA where T J(MAX) is the maximum junction temperature, T A is the ambient temperature, and θ JA is the junction to ambient thermal resistance. For recommended operating condition specifications, the maximum junction temperature is C. The junction to ambient thermal resistance, θ JA, is layout dependent. For SOT- package, the thermal resistance, θ JA, is 8. C/ W on a standard JEDEC -7 four-layer thermal test board. SC-8 package, the thermal resistance, θ JA, is.6 C/ W on a standard JEDEC -7 four-layer thermal test board. The maximum power dissipation at T A = C can be calculated by the following formula : P D(MAX) = ( C C) / (8. C/W) =.W for SOT- package P D(MAX) = ( C C) / (.6 C/W) =.9W for SC-8 package The maximum power dissipation depends on the operating ambient temperature for fixed T J(MAX) and thermal resistance, θ JA. The derating curve in Figure allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. Copyright Richtek Technology Corporation. All rights reserved. DS98- May

12 Outline Dimension D e H L C B b b A e A Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A A....6 B...7. b.... b C D.8... e.9.7 H L SOT- Surface Mount Package Copyright Richtek Technology Corporation. All rights reserved. DS98- May

13 D e H L C B b b A e A Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A.8... A.... B.... b b.... C D e.. H L SC-8 Surface Mount Package Richtek Technology Corporation F, No., Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (886)6789 Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries. DS98- May