LM3702XDBP-308

LM3702/LM3703 Microprocessor Supervisory Circuits with Low Line Output and Manual Reset September 2003 LM3702/LM3703 Microprocessor Supervisory Circuits with Low Line Output and Manual Reset General Description The LM3702/LM3703 series of microprocessor supervisory circuits provide the maximum flexibility for monitoring power supplies and battery controlled functions in systems without backup batteries. The LM3702/LM3703 series are available in a 9-bump micro SMD package. Built-in features include the following: Reset: Reset is asserted during power-up, power-down, and brownout conditions. RESET is guaranteed down to VCC of 1.0V. Manual Reset Input: An input that asserts reset when pulled low. Low Line Output: This early power failure warning indicator goes low when the supply voltage drops to a value which is 2% higher than the reset threshold voltage. n n n n n n n n No external components required Manual-Reset input RESET (LM3702) or RESET (LM3703) outputs Precision supply voltage monitor Factory programmable Reset Timeout Delay Available in micro SMD package for minimum footprint ± 0.5% Reset threshold accuracy at room temperature ± 2% Reset threshold accuracy over temperature extremes n Reset assertion down to 1V VCC (RESET option only) n 28 µA VCC supply current Applications n n n n Embedded Controllers and Processors Intelligent Instruments Automotive Systems Critical µP Power Monitoring Features n Standard Reset Threshold voltage: 3.08V n Custom Reset Threshold voltages: For other voltages between 2.2V and 5.0V in 10mV increments, contact National Semiconductor Corp. Typical Application 20011503 © 2003 National Semiconductor Corporation DS200115 www.national.com LM3702/LM3703 Connection Diagram Top View (looking from the coating side) micro SMD 9 Bump Package BPA09 20011501 Pin Descriptions Bump No. A1 B1 C1 Name MR VCC RESET Function Manual-Reset input. When MR is less than VMRT (Manual Reset Threshold) RESET/RESET is engaged. Power Supply input. Reset Logic Output. Pulses low for tRP (Reset Timeout Period) when triggered, and stays low whenever VCC is below the reset threshold or when MR is below VMRT. It remains low for tRP after either VCC rises above the reset threshold, or after MR input rises above VMRT (LM3702 only). Reset Logic Output. RESET is the inverse of RESET (LM3703 only). Low-Line Logic Output. Early Power-Fail warning output. Low when VCC falls below VLLOT (Low-Line Output Threshold). This output can be used to generate an NMI (Non-Maskable Interrupt) to provide an early warning of imminent power-failure. Ground reference for all signals. No Connect. No Connect. Test input used at factory only. Leave floating. RESET C3 LLO B3 A2, A3, C2 B2 GND NC NC www.national.com 2 LM3702/LM3703 Block Diagram 20011505 3 www.national.com LM3702/LM3703 Ordering Information 20011504 *For other voltages between 2.2V and 5.0V, please contact National Semiconductor sales office. LM3702/LM3703 Part Number LM3702XCBP-308 LM3702XCBPX-308 LM3703XCBP-308 LM3703XCBPX-308 LM3703XDBP-308 LM3703XDBPX-308 LM3702YABP-308 LM3702ABPX-308 LM3702YDBP-220 LM3702YDBPX-220 %% is the datecode and will vary with time. Output totem-pole totem-pole totem-pole totem-pole totem-pole totem-pole open-drain open-drain open-drain open-drain Reset Timeout Period 200ms 200ms 200ms 200ms 1600ms 1600ms 1.4ms 1.4ms 1600ms 1600ms Package Marking %%I2 %%I2 %%I3 %%I3 %%124 %%124 %%131 %%131 %%125 %%125 Table Of Functions Part Number LM3702 LM3703 * = available upon request. Contact National Active Low Reset x Active High Reset x Output (X = totem-pole) (Y = open-drain) X, Y* X Reset Timeout Period Customized Customized Manual Reset x x Low Line Output x x www.national.com 4 LM3702/LM3703 Absolute Maximum Ratings (Note 1) Power Dissipation (Note 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (VCC) All Other Inputs ESD Ratings (Note 2) Human Body Model Machine Model −0.3V to 6.0V −0.3V to VCC + 0.3V 1.5kV 150V Operating Ratings (Note 1) Temperature Range −40˚C ≤ TJ ≤ 85˚C LM3702/LM3703 Series Electrical Characteristics Limits in the standard typeface are for TJ = 25˚C and limits in boldface type apply over full operating range. Unless otherwise specified: VCC = +2.2V to 5.5V. Symbol VCC ICC Parameter Operating Voltage Range: VCC VCC Supply Current Reset Threshold LM3702 LM3703 All inputs = VCC; all outputs floating Conditions Min 1.0 1.2 28 Typ Max 5.5 5.5 50 Units POWER SUPPLY V µA RESET THRESHOLD VRST VCC falling VCC falling: TA = 0˚C to 70˚C VRSTH tRP Reset Threshold Hysteresis Reset Timeout Period Reset Reset Reset Reset Timeout Timeout Timeout Timeout Period Period Period Period = = = = A B C D 1 20 140 1120 −0.5 −2 −1.5 0.0032 • VRST 1.4 28 200 1600 20 2 40 280 2240 VRST +0.5 +2 +1.5 mV % ms tRD VCC to Reset Delay RESET VCC falling at 1mV/µs µs RESET (LM3703) VOL VCC > 2.25V, ISINK = 900µA VCC > 2.7V, ISINK = 1.2mA VCC > 4.5V, ISINK = 3.2mA VOH RESET VCC > 1.2V, ISOURCE = 50µA VCC > 1.8V, ISOURCE = 150µA VCC > 2.25V, ISOURCE = 300µA VCC VCC ILKG Output Leakage Current RESET 0.8 VCC 0.8 VCC 0.8 VCC 0.8 VCC VCC − 1.5V 1.0 µA V 0.3 0.3 0.4 V > 2.7V, ISOURCE = 500µA > 4.5V, ISOURCE = 800µA VRESET = 5.5V RESET (LM3702) VOL VCC > 1.0V, ISINK = 50µA VCC > 1.2V, ISINK = 100µA VCC > 2.25V, ISINK = 900µA VCC VCC VOH RESET VCC VCC VCC 0.3 0.3 0.3 0.3 0.4 0.8 VCC 0.8 VCC VCC − 1.5V V > > > > > 2.7V, ISINK = 1.2mA 4.5V, ISINK = 3.2mA 2.25V, ISOURCE = 300µA 2.7V, ISOURCE = 500µA 4.5V, ISOURCE = 800µA 5 www.national.com LM3702/LM3703 LM3702/LM3703 Series Electrical Characteristics Symbol MR VMRT VMRTH RMR tMD tMR LLO VOL LLO Output Voltage VCC > 2.25V, ISINK = 900µA VCC > 2.7V, ISINK = 1.2mA VCC > 4.5V, ISINK = 3.2mA VOH VCC VCC VCC LLO OUTPUT VLLOT LLO Output Threshold (VLLO − VRST, VCC falling) Low-Line Comparator Hysteresis Low-Line Comparator Delay VCC falling at 1mV/µs MR Input Threshold MR Threshold Hysteresis MR Pull-up Resistance MR to Reset Delay MR Pulse Width MR, Low MR, High MR falling: VCC = VRST MAX (Continued) Limits in the standard typeface are for TJ = 25˚C and limits in boldface type apply over full operating range. Unless otherwise specified: VCC = +2.2V to 5.5V. Parameter Conditions Min Typ Max 0.8 2.0 to 5.5V 35 0.0032 • VRST 56 12 25 0.3 0.3 0.4 0.8 VCC 0.8 VCC VCC − 1.5V 1.01 • VRST 1.02 • VRST 1.03 • VRST V V 75 Units V mV kΩ µS µS > 2.25V, ISOURCE = 300µA > 2.7V, ISOURCE = 500µA > 4.5V, ISOURCE = 800µA VLLOTH 0.0032 • VRST mV tCD 20 µs Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed conditions. Note 2: The Human Body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin. Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal resistance, θJ-A, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperture is calculated using: Where the value of θJ-A for the micro SMD package is 220˚C/W. www.national.com 6 LM3702/LM3703 Typical Performance Characteristics Supply Current vs Supply Voltage 3.3V Supply Current vs Temperature 20011511 20011515 Normalized Reset Threshold Voltage vs Temperature Reset Timeout Period vs VCC 20011512 20011532 Reset Timeout Period vs Temperature Max. Transient Duration vs Reset Comparator Overdrive (VCC = 3.3V) 20011510 20011516 7 www.national.com LM3702/LM3703 Typical Performance Characteristics Low-Line Comparator Propagation Delay vs Temperature (Continued) 20011514 www.national.com 8 LM3702/LM3703 Circuit Information RESET OUTPUT The Reset input of a µP initializes the device into a known state. The LM3702/LM3703 microprocessor supervisory circuits assert a forced reset output to prevent code execution errors during power-up, power-down, and brownout conditions. RESET is guaranteed valid for VCC > 1V. Once VCC exceeds the reset threshold, an internal timer maintains the output for the reset timeout period. After this interval, reset goes high. The LM3702 offers an active-low RESET; The LM3703 offers an active-high RESET. Any time VCC drops below the reset threshold (such as during a brownout), the reset activates. When VCC again rises above the reset threshold, the internal timer starts. Reset holds until VCC exceeds the reset threshold for longer than the reset timeout period. After this time, reset releases. The Manual Reset input (MR) will initiate a forced reset also. See the Manual Reset Input section. RESET THRESHOLD The LM3702/LM3703 family is available with a reset voltage of 3.08V. Other reset thresholds in the 2.20V to 5.0V range, in steps of 10 mV, are available; contact National Semiconductor for details. MANUAL RESET INPUT (MR) Many µP-based products require a manual reset capability, allowing the operator to initiate a reset. The MR input is fully debounced and provides an internal 56 kΩ pull-up. When the MR input is pulled below VMRT (1.225V) for more than 25 µs, reset is asserted after a typical delay of 12 µs. Reset remains active as long as MR is held low, and releases after the reset timeout period expires after MR rises above VMRT. Use MR with digital logic to assert or to daisy chain supervisory circuits. It may be used as another low-line comparator by adding a buffer. LOW-LINE OUTPUT (LLO) The low-line output comparator is typically used to provide a non-maskable interrupt to a µP when VCC begins falling. LLO monitors VCC and goes low when VCC falls below VLLOT (typically 1.02 • VRST) with hysteresis of 0.0032 • VRST. SPECIAL PRECAUTIONS FOR THE MICRO SMD PACKAGE As with most integrated circuits, the LM3702 and LM3703 are sensitive to exposure from visible and infrared (IR) light radiation. Unlike a plastic encapsulated IC, the micro SMD package has very limited shielding from light, and some sensitivity to light reflected from the surface of the PC board or long wavelength IR entering the die from the side may be experienced. This light could have an unpredictable affect on the electrical performance of the IC. Care should be taken to shield the device from direct exposure to bright visible or IR light during operation. MICRO SMD MOUNTING The micro SMD package requires specific mounting techniques which are detailed in National Semiconductor Application Note AN-1112. Referring to the section Surface Mount Technology (SMT) Assembly Considerations, it should be noted that the pad style which must be used with the 9-pin package is the NSMD (non-solder mask defined) type. For best results during assembly, alignment ordinals on the PC board may be used to facilitate placement of the micro SMD device. 9 www.national.com LM3702/LM3703 Timing Diagrams 20011528 FIGURE 1. LM3702 Reset Time with MR 20011529 FIGURE 2. LLO Output www.national.com 10 LM3702/LM3703 Typical Application Circuits 20011524 FIGURE 3. LM3703 Power-On Delay 11 www.national.com LM3702/LM3703 Typical Application Circuits (Continued) 20011522 FIGURE 4. Regulator/Switch with Long-Term Overvoltage Lockout Prevents Overdissipation in Linear Regulator 20011531 FIGURE 5. Switch Debouncer www.national.com 12 LM3702/LM3703 Microprocessor Supervisory Circuits with Low Line Output and Manual Reset Physical Dimensions unless otherwise noted inches (millimeters) NOTES: UNLESS OTHERWISE SPECIFIED 1. EPOXY COATING 2. 63Sn/37Pb EUTECTIC BUMP 3. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD. 4. PIN 1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE NUMBERED COUNTER CLOCKWISE. 5. XXX IN DRAWING NUMBER REPRESENTS PACKAGE SIZE VARIATION WHERE X1 IS PACKAGE WIDTH, X2 IS PACKAGE LENGTH AND X3 IS PACKAGE HEIGHT. 6.NO JEDEC REGISTRATION AS OF AUG.1999. 9 bump micro SMD Package NS Package Number BPA09FFB The dimensions of X1, X2 and X3 are given below X1 = 1.412mm X2 = 1.412mm X3 = 0.850mm LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) 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. National Semiconductor Americas Customer Support Center Email: new.feedback@nsc.com Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Asia Pacific Customer Support Center Email: ap.support@nsc.com National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: jpn.feedback@nsc.com Tel: 81-3-5639-7560 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.