AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Features The AAT3526/7/8 PowerManager™ products are members of AATI's Total Power Management IC™ (TPMIC™) product family. These microprocessor reset circuits are ideal for monitoring voltage supplies in portable systems, where extended battery life is critical. They provide a low cost, reliable solution by eliminating external components. The AAT3526/7/8 products operate by monitoring the system power supply voltage. When the input voltage drops below a fixed threshold, the device asserts a reset signal for a minimum of 150ms after VCC has risen back above the fixed threshold. They are guaranteed to operate down to 1.2V and designed to ignore fast line transients appearing on VCC. The AAT3526/7/8 series is available with three output stage versions: AAT3526 push-pull active low output, AAT3527 push-pull active high output and AAT3528 open drain active low output. The quiescent supply current is extremely low, typically 1µA, making this device ideal for portable battery operated equipment. • • • • • • • The AAT3526/7/8 are available in a 4 pin SOT143 package and are specified over -40° to 85°C operating temperature range. PowerManager™ 1.2V to 5.5V Input voltage range Operation down to 1.2V Extremely low quiescent current: less than 2µA High accuracy detection threshold: ±1.5% Monitor Power Supply Voltages Fixed thresholds from 2.2V to 4.6V Minimum 150ms reset pulse width with fast delay time <20µs Debounced Manual Reset Input Available output configurations: • Open-drain output • CMOS active high output • CMOS active low output Temp range -40 to 85°C 4 pin SOT143 package • • • • Applications • • • • • Notebook Computers Cell Phones Portable Electronics Embedded Systems Intelligent Instruments Typical Application VCC VCC VCC * 100k (nominal) MR AAT3526 AAT3527 RESET (RESET) AAT3528 GND RESET uP INPUT GND *AAT3528 Only 3526.2002.1.0.62 1 Advanced Information General Description AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Pin Descriptions AAT3526, 3527, 3528 (SOT143) Pin # Symbol 1 GND Function Ground connection RESET (AAT3527) RESET output remains high while VCC is below the reset threshold and remains so for a minimum of 150ms after VCC raises above the reset threshold. RESET (AAT3526, AAT3528) RESET output remains low while VCC is below the reset threshold and remains so for a minimum of 150ms after VCC raises above the reset threshold 3 MR Manual Reset active low input. A logic low signal on MR asserts a reset condition. Asserted reset continues as long as MR is low and for a minimum of 150ms after MR returns high 4 Vcc Supply Voltage (+1.2V to +5.5V) 2 Part Number Descriptions Part Number Output Type AAT3526 Reset Output Push Pull Active Low with Delay AAT3527 Reset Output Push Pull Active High with Delay AAT3528 Reset Output Open Drain Active Low with Delay Pin Configuration SOT143 (Top View) GND (RESET) RESET 2 1 4 VCC 2 3 MR 3526.2002.1.0.62 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Absolute Maximum Ratings Symbol (TA=25°C unless otherwise noted) Description Value Units VCC VCC to GND -0.3 to 5.5 V VMR MR to GND -0.3 to VCC+0.3 V RESET to GND (Push-Pull Output) -0.3 to VCC+0.3 VRESET IVCC, IMR IRESET dVcc/dt TJ TLEAD V RESET to GND (Open Drain Output) -0.3 to 5.5 Maximum Continuous Input Current 20 mA RESET/RESET Current 20 mA Rate of rise of VCC 100 V/µs -40 to 150 °C 300 °C Operating Junction Temperature Range Maximum Soldering Temperature (at Leads) for 10s Note: Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum rating should be applied at any one time. Thermal Information Symbol Description Value Units ΘJA Maximum Thermal Resistance (SOT143) 200 °C/W PD Maximum Power Dissipation (SOT143)1 320 mW 1 Note 1: Mounted on an FR4 board. 3526.2002.1.0.62 3 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Electrical Characteristics (VIN = 5V, TA = -40 to 85°C unless otherwise noted. Typical values are at TA=25°C, VCC = 5V for 4.63/4.38V versions, VCC = 3.3V for 3.08/2.93V versions, VCC = 3.0V for 2.63V versions and VCC = 2.5V for 2.32/2.2V versions ) Symbol VCC Operation Voltage IQ Quiescent Current VTH ∆VTH/°C tP tRDY tMR MRGI tMD RESET Threshold (Table 1) RESET Threshold Tempco RESET Propagation Delay RESET Active Timeout Period MR Minimum Pulse Width MR Glitch Immunity MR to Reset Propagation Delay VIH MR Input Threshold VIL MR Input Threshold RMR MR Pull-Up Resistance VOL RESET Low Output Voltage AAT3526, AAT3528 VOH 4 Description RESET High Output Voltage AAT3526 VOL RESET Low Output Voltage AAT3527 VOH RESET High Output Voltage AAT3527 IDOFF RESET leakage current, AAT3528 Conditions Min Typ TA = 0ºC to +70ºC TA = -40ºC to +85ºC VCC = 5.5V VCC = 3V TA = 25ºC TA = -40ºC to +85ºC 1.0 1.2 5.5 V 5.5 1.05 3 µA 0.85 2 VTH VTH +1.5% V VTH VTH +2.5% 40 ppm/°C 15 µs 250 400 ms µs 100 ns 0.5 µs VTH -1.5% VTH -2.5% VCC = VTH to (VTH -100mV) 150 10 VCC VCC VCC VCC = = = = VTH(MAX), VTH(MAX), VTH(MAX), VTH(MAX), VTH VTH VTH VTH ≥ 4.38V < 4.38V ≥ 4.38V < 4.38V 2.3 0.7 × VCC 10 ISINK =1.6mA, VCC > 2.1V, RESET asserted ISINK =100µA, VCC >1.2V, RESET asserted ISOURCE = 800 µA ISINK =1.2mA, VCC > 1.2V, RESET not asserted ISINK = 3.2mA, VCC > 4.5V, RESET not asserted ISOURCE = 500µA, VCC > 2.1V, RESET asserted ISOURCE = 50µA, VCC > 1.2V, RESET asserted VCC > VTH Max Units V 20 0.8 0.25 × VCC 30 0.3 0.4 VCC -1.5 V kΩ V V 0.3 0.4 V 0.8VCC V 0.8VCC 1 µA 3526.2002.1.0.62 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Typical Characteristics Normalized Reset Threshold vs. Temperature Supply Current vs. Temperature 1.20 VCC=5V Normalized Threshold Supply Current (µA) 1.40 1.00 0.80 VCC=3V 0.60 0.40 0.20 0.00 -40 -20 0 20 40 60 1.003 1.002 1.001 1.000 0.999 0.998 0.997 80 -40 -20 0 Temperature (°C) 280 260 240 220 200 180 160 20 40 60 80 100 Temperature (°C) Reset Propagation Delay (µs) Power-Up Reset Timeout (ms) 300 0 60 80 Power-Down Reset Propagation Delay vs. Temperature 320 -20 40 Temperature (°C) Power-Up Reset Timeout vs. Temperature -40 20 30 25 VOD=10mV 20 15 10 VOD=100mV 5 0 -40 -20 0 20 40 60 80 Temperature (°C) Maximum Transient Duration vs. Reset Threshold Overdrive Maximum Transient Duration (µS) 400 350 300 250 200 150 100 50 0 1 10 100 1000 Reset Threshold Overdrive, VTH-VCC (mV) 3526.2002.1.0.62 5 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Functional Block Diagram MR VCC Reset Generator + Timer RESET (RESET) Oscillator VREF GND Functional Description General During start-up, the reset pin on a microprocessor ensures that it is fully reset and starts up in a known condition. The AAT3526/7/8 series of microprocessor reset devices monitor the supply voltage to a VTH VTH microprocessor and assert a reset signal whenever the VCC voltage falls below a factory programmed threshold. This threshold is accurate within +/-1.5% at 25ºC and within +/- 2.5% over the entire operating temperature range. The reset signal remains asserted for a minimum of 150ms after VCC has risen above the threshold as shown in Figure 1. VTH VCC tRDY tRDY Figure 1: Reset Timing Diagram 6 3526.2002.1.0.62 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Applications Information Reset Output Options The AAT3528 has an active low open drain output and the AAT3526/7 have a push-pull output. The AAT3528 may be used in multiple voltage systems, with an external pull-up resistor. This allows the AAT3528 to interface to microprocessors with higher supply voltages up to 5.5V (Figure 2). In the event of a power down or brown-out condition the reset signal remains valid until the VCC drops below 1.2V. To ensure validity down to ground an external 100kΩ resistor should be connected between the RESET output and GND. Manual Reset Input A logic low signal on MR asserts a reset condition. Reset continues to be asserted as long as MR is low and for a minimum of 150ms after MR returns high. This input is internally pulled up to VCC via a 20kΩ resistor, so leaving the pin unconnected is acceptable if manual reset function is not needed. The MR input is internally debounced which allows use of a mechanical switch. It should be a normally-open momentary switch connected from MR to GND. Additionally, the MR pin can be driven from TTL, CMOS, or open drain logic outputs. Supply Voltage Transient Behavior In some cases fast negative transients of short duration can appear on the VCC power supply. The AAT3526/7/8 series devices provide some immunity to line transients which can generate invalid reset pulses. Figure 1 shows typical behavior to short duration pulses verses RESET comparator overdrive. As shown in the Maximum Transient Duration vs. Reset Threshold Overdrive graph, when the transient voltage becomes larger, the time allowed before asserting a reset becomes shorter. e.g. typically a transient of 100mV below the reset threshold would have to present for more than 50µs to cause a reset. Immunity can be increased by the addition of a small by-pass capacitor of 0.1µF connected as close to the VCC pin as possible. +3.3V +5.0V VCC VCC 100k AAT3528 MR RESET RESET INPUT GND 5V System GND Figure 2: Using AAT3528 Open Drain Output with Multiple Supplies 3526.2002.1.0.62 7 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Factory Trimmed Reset Thresholds* and Ordering Information Table 1 Ordering Part Number Marking Reset Threshold Voltage, VTH (V) TA = 40 to 85ºC TA = 25ºC Min Typ Max Min Max AAT3526ICX-2.32-200-T1 AAT3527ICX-2.32-200-T1 AAT3528ICX-2.32-200-T1 2.285 2.320 2.355 2.262 2.378 AAT3526ICX-2.63-200-T1 AAT3527ICX-2.63-200-T1 AAT3528ICX-2.63-200-T1 2.591 2.630 2.669 2.564 2.696 AAT3526ICX-2.93-200-T1 AAT3527ICX-2.93-200-T1 AAT3528ICX-2.93-200-T1 2.886 2.930 2.974 2.857 3.003 AAT3526ICX-3.08-200-T1 AAT3527ICX-3.08-200-T1 AAT3528ICX-3.08-200-T1 3.034 3.080 3.126 3.003 3.157 AAT3526ICX-4.38-200-T1 AAT3527ICX-4.38-200-T1 AAT3528ICX-4.38-200-T1 4.314 4.380 4.446 4.271 4.490 AAT3526ICX-4.63-200-T1 AAT3527ICX-4.63-200-T1 AAT3528ICX-4.63-200-T1 4.561 4.630 4.699 4.514 4.746 *Contact Local Sales Office for custom trimmed options 8 3526.2002.1.0.62 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset Package Information SOT143 B Dim S e1 A A1 B B1 C D E E1 E2 H I S Θ CL CL E H PIN 1 e2 B1 D θ A Millimeters Min Max 0.787 1.194 0.025 1.027 0.356 0.559 0.762 0.965 0.086 0.152 2.667 3.048 1.194 1.397 1.803 2.007 0.200 BSC 2.083 2.489 0.102 0.305 0.450 0.600 0° 8° Inches Min Max 0.031 0.047 0.001 0.005 0.014 0.022 0.030 0.038 0.0034 0.006 0.105 0.120 0.047 0.055 0.071 0.079 0.008 BSC 0.082 0.098 0.004 0.012 0.018 0.024 0° 8° C A1 CL 3526.2002.1.0.62 CL I 9 AAT3526/7/8 MicroPower Supervisory Circuit with Manual Reset This page intentionally left blank. Advanced Analogic Technologies, Inc. 1250 Oakmead Parkway, Suite 310, Sunnyvale, CA 94086 Phone (408) 524-9684 Fax (408) 524-9689 10 3526.2002.1.0.62