LTC1042 Window Comparator FEATURES DESCRIPTIO Micropower 1.5W (1 Sample/Second) The LTC 1042 is a monolithic CMOS window comparator manufactured using Linear Technologys enhanced Wide Supply Range 2.8V to 16V LTCMOS silicon gate process. Two high impedance High Accuracy voltage inputs, CENTER and WIDTH/2, define the middle Center Error 1mV Max and width of the comparison window. Whenever the input Width Error 0.15% Max voltage, V , is inside the window the WITHIN WINDOW IN Wide Input Voltage Range output is high. The ABOVE WINDOW output is high + V to Ground whenever V is above the window. By interchanging V IN IN TTL Outputs with 5V Supply and CENTER, the ABOVE WINDOW output becomes Two Independent Ground-Referred Control Inputs BELOW WINDOW and is high if V is below the window. IN Small Size 8-Pin MiniDIP Sampling techniques provide high impedance voltage inputs that can common mode to both supply rails U + (V and GND). An important feature of the inputs is their APPLICATIO S non-interaction. Also the device is effectively chopper Fault Detectors stabilized, giving it extremely high accuracy over Go/No-Go Testing all conditions of temperature, power supply and input Microprocessor Power Supply Monitor voltage range. , LTC and LT are registered trademarks of Linear Technology Corporation. Another benefit of the sampling techniques used to design LTCMOS is a trademark of Linear Technology Corp. the LTC1042 is the extremely low power consumption. When the device is strobed, it internally turns on the power to the comparators, samples the inputs, stores the outputs in CMOS latches and then turns off power to the compara- tors. This all happens in about 80s. Average power can be made small, almost arbitrarily, by lowering the strobe rate. The device can be self-strobed using an external RC network or strobed externally by driving the OSC pin with a CMOS gate. TYPICAL APPLICATIO Battery-Powered Remote Freezer Alarm Total Supply Current vs Sampling Frequency + V 10000 + HI = TEMPERATURE V = 6V I T BETWEEN 1 8 150k 150k 1000 10M 5% 26F AND 31F I T 2 7 1F 100 3 LTC1042 6 HI = TEMPERATURE 4 5 3V TO 16V ABOVE 31F T R1* 10 1F 7.5k LTC1042 SUPPLY CURRENT 0.05F 1 R2* 576 FOR THIS APPLICATION 0.1 f 1HZ S 0.01 T = YELLOW SPRINGS INSTRUMENT CO., INC. P/N 44007 0.1 110 100 1000 10000 ALL RESISTORS 1% UNLESS OTHERWISE SPECIFIED SAMPLING FREQUENCY, f (Hz) S *OTHER TEMPERATURE BANDS MAY BE SELECTED BY CHOOSING APPROPRIATE VALUES FOR R1 AND R2 LTC1042 TA02 LTC1042 A01 1042fa 1 TOTAL SUPPLY CURRENT, I (A) T U ULTC1042 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW ORDER + Total Supply Voltage (V to GND) ............................ 18V WITHIN + 1 8 V WINDOW PART NUMBER + Input Voltage ..................................... V +0.3V to 0.3V CENTER 2 7 OSC Operating Temperature Range ABOVE LTC1042CN8 V 3 6 IN WINDOW LTC1042C ......................................... 40C to 85C GND 4 5 WIDTH / 2 LTC1042M (OBSOLETE) ................. 55C to 125C N8 PACKAGE Storage Temperature Range ................. 55C to 150C 8-LEAD PDIP T = 110C, = 150C/W JMAX JA Lead Temperature (Soldering, 10 sec).................. 300C J8 PACKAGE Output Short Circuit Duration .......................Continuous LTC1042MJ8 8-LEAD CERDIP OBSOLETE PACKAGE Consider the N8 Package as an Alternate Source LTC1042 POI01 Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25C. A SYMBOL PARAMETER TEST CONDITIONS MIN TYP MAX UNITS + Center Error (Note 3) V = 2.8V to 6V (Note 2) 0.3 1mV + + 0.05 0.15 % WIDTH/2 + V = 6V to 15V (Note 2) 1 3mV ++ 0.05 0.15 % WIDTH/2 + Width Error (Note 4) V = 2.8V to 6V (Note 2) 0.6 2mV ++ 0.1 0.3 % WIDTH/2 + V = 6V to 15V (Note 2) 2 6 mV ++ 0.1 0.3 % WIDTH/2 + I Input Bias Current V = 5V, T = 25C, OSC = GND 0.3 nA BIAS A V , CENTER and WIDTH/2 Inputs IN R Average lnput Resistance f = 1kHz (Note 5) 10 15 M IN S + Input Voltage Range GND V V PSR Power Supply Range 2.8 16 V + I Power Supply ON V = 5V 1.2 3 mA S(ON) Current (Note 6) + I Power Supply OFF V = 5V, LTC1042C 0.001 0.5 A S(OFF) Current (Note 6) LTC1042M 0.001 5.0 A + T Response Time (Note 7) V = 5V 80 100 s D Output Levels + V Logic 1 Output V = 4.75V, l = 360A 2.4 4.4 V OH OUT + V Logical 0 Output V = 4.75V, l = 1.6mA 0.25 0.45 V OL OUT 1042fa 2 U WWW