AIC811/AIC812 Reset Circuits with Manual Reset Input FEATURES DESCRIPTION Ultra Low Supply Current 1µA(typ.) AIC811/AIC812 are low-power microprocessor (µP) Guaranteed Reset Valid to Vcc=0.9V supervisory circuits used to monitor power supplies in Available in two Output Types: Push-Pull Active µP and digital systems. They provide applications with Low (AIC811), Push-Pull Active High (AIC812) benefits of circuit reliability and low cost by eliminating 140ms Min. Power-On Reset Pulse Width Internally Fixed Threshold 2.3V, 2.6V, 2.9V, external components. AIC811/AIC812 also offer a 3.1V, 4.0V, 4.4V, and 4.6V manual reset input. Tight Voltage Threshold Tolerance: 1.5% Low profile Package: SOT-23-5 These devices perform as valid singles in applications with Vcc ranging from 6.0V down to 0.9V. The reset APPLICATIONS signal lasts for a minimum period of 140ms whenever Notebook Computers VCC supply voltage falls below preset threshold. Both Digital Still Cameras AIC811 and AIC812 were designed with a reset PDAs comparator to help identify invalid signals, which last Critical Microprocessor Monitoring less than 140ms. The only difference between them is that they have an active-low RESET output and active-high RESET output, respectively. Low supply current (1µA) makes AIC811/AIC812 ideal for portable equipment. The devices are available in SOT-23-5 package. TYPICAL APPLICATION CIRCUIT VCC VCC VCC AIC811 (AIC812) RESET (RESET) MR µP RESET INPUT GND GND Pushbutton Switch Analog Integrations Corporation Si-Soft Research Center DS-811P-03 010405 3A1, No.1, Li-Hsin Rd. I, Science Park, Hsinchu 300, Taiwan, R.O.C. TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1 AIC811/AIC812 ORDERING INFORMATION AIC811-XXXXXX AIC812-XXXXXX PIN CONFIGURATION SOT-23-5 TOP VIEW 1: GND 2: NC 3: RESET (RESET) 4: MR 5: VCC PACKING TYPE TR: TAPE & REEL BG: BAG PACKAGE TYPE V: SOT-23-5 5 1 4 2 3 C: COMMERCIAL P: LEAD FREE COMMERCIAL RESET THRESHOLD VOLTAGE 23: 2.3V 26: 2.6V 29: 2.9V 31: 3.1V 40: 4.0V 44: 4.4V 46: 4.6V (Additional voltage versions with a unit of 0.1V within the voltage range from 1.5V to 5.5V for this product line may be available on demand with prior consultation with AIC.) Example: AIC811-31CVTR 3.1V version, in SOT-23-5 Package & Tape & Reel Packing Type AIC811-31PVTR 3.1V version, in Lead Free SOT-23-5 Package & Tape & Reel Packing Type SOT-23-5 Marking Part No. Marking Part No. Marking AIC811-23CV BQ23 AIC812-23CV BR23 AIC811-26CV BQ26 AIC812-26CV BR26 AIC811-29CV BQ29 AIC812-29CV BR29 AIC811-31CV BQ31 AIC812-31CV BR31 AIC811-40CV BQ40 AIC812-40CV BR40 AIC811-44CV BQ44 AIC812-44CV BR44 AIC811-46CV BQ46 AIC812-46CV BR46 2 AIC811/AIC812 Part No. Marking Part No. Marking AIC811-23PV BQ23P AIC812-23PV BR23P AIC811-26PV BQ26P AIC812-26PV BR26P AIC811-29PV BQ29P AIC812-29PV BR29P AIC811-31PV BQ31P AIC812-31PV BR31P AIC811-40PV BQ40P AIC812-40PV BR40P AIC811-44PV BQ44P AIC812-44PV BR44P AIC811-46PV BQ46P AIC812-46PV BR46P ABSOLUTE MAXIMUM RATINGS VCC -0.3V ~6.5V RESET, RESET -0.3V ~ (VCC+0.3V) Input Current (VCC, MR ) 20mA Output Current (RESET or RESET ) 20mA Continuous Power Dissipation (TA = +70°C) 320mW Operating Junction Temperature Range -40°C ~ 85°C Junction Temperature 125°C Storage Temperature Range - 65°C ~ 150°C Lead Temperature (Soldering) 10 sec 260°C Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. TEST CIRCUIT 1 2 3 GND VCC NC MR 5 4 Iin Vin RESET AIC811 Pushbuttom Switch 3 AIC811/AIC812 ELECTRICAL CHARACTERISTICS (Typical values are at TA=25°C, unless otherwise specified) (Note 1) PARAMETER SYMBOL Operating Voltage Range VCC Supply Current ICC TEST CONDITIONS VCC = VTH +0.1V AIC811-26 AIC811-29 VTH AIC811-31 AIC811-40 AIC811-44 AIC811-46 TA=+25°C 2.254 TA=+25°C 2.561 TA= -40°C to +85°C 2.548 TA=+25°C 2.857 TA= -40°C to +85°C 2.842 TA=+25°C 3.054 TA= -40°C to +85°C 3.038 TA=+25°C 3.940 TA= -40°C to +85°C 3.920 TA=+25°C 4.334 TA= -40°C to +85°C 4.312 TA=+25°C 4.531 TA=-40°C to +85°C 4.508 TRD VCC=VTH to (VTH –0.1V), VTH=3.1V Reset Active Timeout Period TRP VCC TA=+25°C = VTH(MAX) TA= -40°C to +85°C TMD Vcc=6V Delay MR Input Threshold VIH RESET Output Voltage MAX. UNIT 6 V 1 3 µA 2.3 2.335 2.346 2.6 2.639 2.652 2.9 2.944 2.958 3.1 3.147 3.162 4.0 4.060 4.4 4.466 4.488 4.6 4.669 4.692 µS 20 140 230 100 560 1030 0.25VCC VIL VOH VCC=VTH+0.1V, ISOURCE=1mA VOL VCC=VTH - 0.1V, ISINK=1mA VOH VCC=VTH+0.1V, ISOURCE=1mA VOL VCC=VTH - 0.1V, ISINK=1mA 20 mS µS 0.5 10 V 4.080 0.7VCC MR Pull-Up Resistance RESET Output Voltage 2.265 TA= -40°C to +85°C VCC to Reset Delay MR to Reset Propagation TYP. 0.9 AIC811-23 Reset Threshold MIN. 30 0.8VCC 0.2Vcc 0.8VCC 0.2Vcc V KΩ V V Note1: Specifications are production tested at TA=25°C. Specifications over the -40°C to 85°C operating temperature range are assured by design, characterization and correlation with Statistical Quality Controls (SQC). Note2: RESET output is for AIC811; RESET output is for AIC812. 4 AIC811/AIC812 TYPICAL PERFORMANCE CHARACTERISTICS 120 1.4 VTH=2.3V Supply Current (µA) 1.3 1.2 1.1 VTH=3.1V 1.0 VTH=4.6V 0.9 0.8 0.7 0.6 Power-Down Reset Delay (µS) 1.5 110 VTH=2.3V VOD=VTH-VCC 100 90 80 70 VOD=50mV 60 50 VOD=100mV 40 30 VOD=200mV 20 10 0 0.5 -20 -40 0 40 20 60 80 100 -60 Temperature (°C) -40 -20 0 20 40 60 80 100 Temperature (°C) Fig 2 Power-Down Reset Delay vs. Temperature Fig 1 Supply Current vs. Temperature VTH=3.1V VOD=VTH-VCC 220 200 Power-Down Reset Delay (µS) Power-Down Reset Delay (µS) 240 180 160 140 VOD=50mV 120 100 80 60 VOD=100mV 40 VOD=200mV 20 0 -60 -40 0 -20 20 40 60 80 VTH=4.6V VOD=50mV 400 VOD=VTH-VCC 300 200 VOD=100mV 100 VOD=200mV 0 100 -60 -40 -20 0 20 40 60 80 100 Temperature (°C) Temperature (°C) Fig 3 Power-Down Reset Delay vs. Temperature Fig 4 Power-Down Reset Delay vs. Temperature Power-Up Reset Timeout (mS) Normalized Reset Threshold (V) 600 1.015 VTH=4.6V 1.010 1.005 1.000 VTH=3.1V 0.995 VTH=2.3V 0.990 0.985 -40 -20 0 20 40 60 80 100 500 400 VTH=3.1V VTH=4.6V 300 200 VTH=2.3V 100 0 -60 -40 -20 0 20 40 60 80 Temperature (°C) Temperature (°C) Fig 5 Normalized Reset Threshold vs. Temperature Fig 6 Power-Up Reset Timeout vs. Temperature 100 5 AIC811/AIC812 BLOCK DIAGRAM VCC RESET (RESET) R1 Bandgap - Reset Generator + RPULL_UP R2 20K GND MR PIN DESCRIPTIONS GND Pin : RESET Pin (AIC811) : RESET Pin (AIC812) : MR Pin : Vcc Pin : Ground. Active low output pin. RESET Output remains low while Vcc below reset threshold. Active high output pin. RESET output remains high while Vcc below reset threshold. Logic low manual reset input. This active-low input has an internal 20kΩ pull-up resistor. It can be driven by a TTL or CMOS, or shorted to ground with a switch. Leave open when unused. Supply voltage. DETAILED DESCRIPTIONS OF TECHNICAL TERMS RESET OUTPUT μP will be activated at a valid reset state. These μP supervisory circuits assert reset to prevent code execution errors during power-up, power-down, or brownout conditions. RESET is guaranteed to be a logic low for VTH>VCC>0.9V. Once VCC exceeds the reset threshold, an internal timer keeps RESET low for the reset timeout period; after this interval, RESET goes high. If a brownout condition occurs (VCC drops below the reset threshold), RESET goes low. Any time VCC goes below the reset threshold, the internal timer resets to zero, and RESET goes low. The internal timer is activated after VCC returns above the reset threshold, and RESET remains low for the reset timeout period. The manual reset input ( MR ) can also initiate a reset. AIC812 has an active-high RESET output that is the inverse of AIC811’s RESET output. 6 AIC811/AIC812 MANUAL RESET INPUT Many μ P-based products require manual reset capability, allowing operators, test technicians, or external logic circuitry to initiate a reset. Logic low on MR asserts reset. Reset will remain asserted for the Reset Active Timeout Period (tRP) after MR returns high. This input has an internal 20K Ω pull-up resistor, so it can be floating if it is not used. MR can be driven with TTL or CMOS-logic levels, or with open-drain/collector outputs. Another alternative is to connect a normal switch from MR to GND to create a manual reset function. Connecting a 0.1µF capacitor from MR to ground can provide noise immunity to prevent noise caused by long cables of MR or noisy environment. BENEFITS OF HIGHLY ACCURATE RESET THRESHOLD AIC811/812 with specified voltage as 5V±10% or 3V±10% are ideal for systems using a 5V±5% or 3V ± 5% power supply. The reset is guaranteed to assert after the power supply falls out of regulation, but before power drops below the minimum specified operating voltage range of the system ICs. The pre-trimmed thresholds are reducing the range over which an undesirable reset may occur. APPLICATION INFORMATION RESET must be valid down to 0V, adding a NEGATIVE-GOING VCC TRANSIENTS In addition to issuing a reset to the μP during pull-down resistor to RESET causes any leakage power-up, power-down, and brownout conditions, AIC811 series are relatively resistant to short-duration negative-going VCC transient. INTERFACING TO μP WITH BIDIRECTIONAL ENSURING A VALID RESET OUTPUT DOWN TO VCC=0 When VCC falls below 0.9V, AIC811 RESET output no longer sinks current; it becomes an open circuit. In this case, high-impedance CMOS logic inputs connecting to RESET can drift to undetermined voltages. Therefore, AIC811/2 with CMOS is perfect for most applications of VCC below 0.9V. However in applications where currents to flow to ground, holding RESET low. RESET PINS μPs with bidirectional reset pins can contend with AIC811/812 reset outputs. If AIC811 RESET output is asserted high and the μP wants to pull it low, indeterminate logic levels may occur. To correct such cases, connect a resistor between AIC811 RESET (or AIC812 RESET) output and theμP reset I/O. Buffer the reset output to other system components. 7 AIC811/AIC812 PHYSICAL DIMENSIONS (unit: mm) SOT-23-5 D A A E E1 S Y M B O L e e1 SEE VIEW B WITH PLATING MILLIMETERS MIN. MAX. A 0.95 1.45 A1 0.05 0.15 A2 0.90 1.30 b 0.30 0.50 c 0.08 0.22 D 2.80 3.00 E 2.60 3.00 E1 1.50 1.70 e 0.95 BSC e1 1.90 BSC c A A2 b SOT-25 SECTION A-A A1 BASE METAL L 0.30 L1 0° 8° 0.25 θ 0.60 0.60 REF GAUGE PLANE SEATING PLANE L1 θ L VIEW B Note: Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AIC product; nor for any infringement of patents or other rights of third parties that may result from its use. We reserve the right to change the circuitry and specifications without notice. Life Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. Life support devices or systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 8