LM27 NSC | Alldatasheet
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Features
n Internal comparator with pin selectable 2˚C or 10˚C hysteresis n No external components required n Open-drain or push-pull digital output; supports CMOS logic levels n Internal temperature sensor with VTEMP output pin n VTEMP output allows after-assembly system testing n Internal voltage reference and DAC for trip-point setting n Currently available in 5-pin SOT-23 plastic package n Excellent power supply noise rejection Key Specifications j Power Supply Voltage 2.7V to 5.5V j Power Supply Current 40µA(max) 15µA(typ) j Hysteresis Temperature 2˚C or 10˚C(typ) j Temperature Trip Point Accuracy ±3˚C (max) LM27CIM5-2HJ Simplified Block Diagram and Connection Diagram 20030701 The LM27CIM5-2HJ has a fixed trip point of 140˚C. For other trip point and output function availability, please see ordering information or contact National Semiconductor. August 2002 LM27 SOT-23,±3˚C Accurate, 120˚C-150˚C Factory Preset Thermostat © 2002 National Semiconductor Corporation DS200307 www.national.com
Ordering Information
For more detailed information on the suffix meaning see the part number template at the end of the Electrical Characteris- tics Section. Contact National Semiconductor for other set points and output options. Order Number Top Mark Number Trip Point Setting Output FunctionBulk Rail 3000 Units in Tape & Reel LM27CIM5-1HJ LM27CIM5X-1HJ T1HJ MA05B 130˚C Open Drain OS LM27CIM5-2HJ LM27CIM5X-2HJ T2HJ MA05B 140˚C Open Drain OS Connection Diagram 20030702 Pin Description Pin Number Pin Name Function Connection
1 HYST Hysteresis control, digital
GND for 10˚C or V+ for 2˚C
2 GND Ground, connected to the
back side of the die through lead frame. System GND TEMP Analog output voltage proportional to temperature Leave floating or connect to a high impedance node. 4V + Supply input 2.7V to 5.5V with a 0.1µF bypass capacitor. For PSRR information seeSection Titled NOISE CONSIDERATIONS. 5O S Overtemperature Shutdown open-drain active low thermostat digital output Controller interrupt, system or power supply shutdown; pull-up resistor≥ 10kΩ OS Overtemperature Shutdown totem-pull active high thermostat digital output Controller interrupt, system or power supply shutdown US Undertemperature Shutdown open-drain active low thermostat digital output System or power supply shutdown; pull-up resistor ≥ 10kΩ US Undertemperature Shutdown totem-pull active high thermostat digital output System or power supply shutdown Note: pin 5 functionality and trip point setting are programmed during LM27 manufacture. LM27 www.national.com 2
Absolute Maximum Ratings(Note 1) Input Voltage 6.0V Input Current at any pin (Note 2) 5mA Package Input Current(Note 2) 20mA Package Dissipation at T A = 25˚C (Note 3) 500mW Soldering Information Vapor Phase (60 seconds) Infrared (15 seconds) 215˚C 220˚C Storage Temperature −65˚C to + 150˚C ESD Susceptibility (Note 4) Human Body Model Machine Model 2500V 250V Operating Ratings(Note 1) Specified Temperature Range TMIN ≤ TA ≤ TMAX LM27CIM −40˚C ≤ TA ≤ +150˚C Positive Supply Voltage (V+) +2.7V to +5.5V Maximum VOUT +5.5V The following specifications apply for V+ = 2.7VDC to 5.5VDC, and VTEMP load current = 0µA unless otherwise specified.Bold- face limits apply for TA =T J =T MIN to TMAX; all other limits TA =T J = 25˚C unless otherwise specified. Typical LM27CIM Units Symbol Parameter Conditions (Note 6) Limits (Limits) (Note 7) Temperature Sensor Trip Point Accuracy (Includes VREF, DAC, Comparator Offset, and Temperature Sensitivity errors) +120˚C Trip Point Hysteresis HYST = GND 10 ˚C HYST = V+ 2˚ C VTEMP Output Temperature Sensitivity −10.82 mV/˚C VTEMP Temperature Sensitivity Error to Equation: 1.8386V 2.7V ≤ V+ ≤ 5.5V ±3 ˚C (max) 4.5V ≤ V+ ≤ 5.5V ±3 ˚C (max) TA = 25˚C ±2.5 ˚C (max) VTEMP Load Regulation −1µA ≤ IL ≤ 0 0.070 mV 0 ≤ IL ≤ +40µA 0.7 mV (max) VTEMP Line Regulation +2.7V ≤ V+ ≤ +5.5V, −0.2 mV/V IS Supply Current 15 22 µA (max) µA (max) Digital Output and Input IOUT(“1”) Logical “1” Output Leakage Current (Note 9) V+ = +5.0V 0.001 1 µA (max) VOUT(“0”) Logical “0” Output Voltage I OUT = +1.2mA and V+≥2.7V; IOUT = +3.2mA and V+≥4.5V; (Note 8)
0.4 V (max)
VOUT(“1”) Logical “1” Push-Pull Output Voltage ISOURCE = 500µA, V+ ≥ 2.7V 0 . 8xV+ V (min) ISOURCE = 800µA, V+≥4.5V V+ − 1.5 V (min) VIH HYST Input Logical ”1“ Threshold Voltage 0 . 8xV+ V (min) VIL HYST Input Logical ”0“ Threshold Voltage 0 . 2xV+ V (max) LM27 www.national.com3
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is 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 test conditions. Note 2: When the input voltage (VI) at any pin exceeds the power supply (VI < GND or VI > V+), the current at that pin should be limited to 5mA. The 20mA maximum package input current rating limits the number of pins that can safely exceed the power supplies with an input current of 5mA to four. Under normal operating conditions the maximum current that pins 2, 4 or 5 can handle is limited to 5mA each. Note 3: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax (maximum junction temperature),θJA (junction to ambient thermal resistance) and TA (ambient temperature). The maximum allowable power dissipation at any temperature is PD =( TJmax–TA)/θJA or the number given in the Absolute Maximum Ratings, whichever is lower. For this device, TJmax = 150˚C. For this device the typical thermal resistance (θJA) of the different package types when board mounted follow: Package Type θJA SOT23-5, MA05B 250˚C/W Note 4: The human body model is a 100pF capacitor discharge through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin. Note 5: See the URL ”http://www.national.com/packaging/“ for other recommendations and methods of soldering surface mount devices. Note 6: Typicals are at TJ =T A = 25˚C and represent most likely parametric norm. Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Note 8: Care should be taken to include the effects of self heating when setting the maximum output load current. The power dissipation of the LM27 would increase by 1.28mW when IOUT=3.2mA and VOUT=0.4V. With a thermal resistance of 250˚C/W, this power dissipation would cause an increase in the die temperature of about 0.32˚C due to self heating. Self heating is not included in the trip point accuracy specification. Note 9: The 1µA limit is based on a testing limitation and does not reflect the actual performance of the part. Expect to see a doubling of the current for every 15˚C increase in temperature. For example, the 1nA typical current at 25˚C would increase to 16nA at 85˚C. Part Number Template The series of digits labeled xyz in the part number LM27CIM-xyz, describe the set point value and the function of the output as follows: The place holders xy describe the set point temperature as shown in the following table. x (10x) y (1x) Temperature (˚C) -H 0 -J 1 -K 2 -L 3 -N 4 -P 5 -R 6 x (10x) y (1x) Temperature (˚C) -S 7 -T 8 -V 9 Z- 1 2 1- 1 3 2- 1 4 3- 1 5 The value of z describes the assignment/function of the output as shown in the following table: Active-Low/High Open-Drain/ Push-Pull OS/US Value of z Digital Output Function 0 0 0 J Active-Low, Open-Drain, OS output 0 0 1 K Active-Low, Open-Drain, US output 110L Active-High, Push-Pull, OS output 1 1 1 N Active-High, Push-Pull, US output For example:
- the part number LM27CIM5-2SJ has TOS = 147˚C, and programmed as an active-low open-drain overtemperature shutdown output.
- the part number LM27CIM5-ZLN has TUS = 123˚C, and programmed as an active-high, push-pull undertemperature shutdown output. Active-high open-drain and active-low push-pull options are available, please contact National Semiconductor for more informa- tion. LM27 www.national.com 4
anywhere in-between 120˚C to 150˚C. LM27CIM5X-2HJ which has a 140˚C trip point.
- Verify that the temperature measured in step one is
C. Observe that OS is now low. E. Observe that OS is now high. B. Drive VTEMP voltage down gradually. C. When OS goes low, note the VTEMP voltage. E. Calculate Ttrig usingEquation (2). B. Calculate THYST using Equation (2). FIGURE 1. Output Pin Options Block Diagrams
Physical Dimensions inches (millimeters) unless otherwise noted 5-Lead Molded SOT-23 Plastic Package, JEDEC Order Number LM27CIM5 or LM27CIM5X 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. 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 Corporation Americas Email: support@nsc.com National Semiconductor Europe 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 National Semiconductor Asia Pacific Customer Response Group Tel: 65-2544466 Fax: 65-2504466 Email: ap.support@nsc.com National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 www.national.com LM27 SOT-23,±3˚C Accurate, 120˚C-150˚C Factory Preset Thermostat 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.