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LINEAR TECHNOLOGY LTC1440/LTC1441/LTC1442 handbook

1. Comparator Response Time vs Comparator Response Time vs Input Overdrive Input Overdrive 5 _ 5 4 4 L4 o Q gt gt E 2 5 2 2 E 1 2 1 0 0 gt gt 0 100 E 100 0 2 2 2 2 1 0 2 4 6 8 10 12 14 16 18 RESPONSE TIME us RESPONSE TIME us 1440 1 2 601 1440 1 2 G02 Comparator Short Circuit Sink Comparator Short Circuit Source Current vs Supply Voltage Current vs Supply Voltage 200 160 TA 25 C 180 140 160 p z 120 140 OUT CONNECTED TO V 100 00 CONNECTED TO 14 V GND 0V 100 80 60 i 2 B 40 40 20 20 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 SUPPLY VOLTAGE V SUPPLY VOLTAGE V 1440 1 2 603 1440 1 2 604 144012fb LI MYR J LIC 1440 LTC 1441 LTC 1442 TYPICAL PERFORMANCE CHARACTERISTICS Comparator Response Time vs Load Capacitance with 100mV Comparator Response Time at Input Overdrive Low Supply Voltage 12 10000 10 A 1000 8 20mV OVERDRIVE E 100 S 6 tPLH 5 B 5 a 4 100mV OVERDRIVE 2 1 0 20 40 60 80 100 10 11 12 13 14 15 16 LOAD CAPACITANCE nF S
2. 01 0 001 0 01 0 1 1 10 CAPACITOR VALUE uF 1440 1 2 F02 Figure 2 Damping Resistance vs Bypass Capacitor Value 1440120 10 LTC 1440 LTC 1441 LTC 1442 APPLICATIONS INFORMATION 1101440 2mV DIV 2ms DIV 1440 1 2 FO3b Figure 3b Reference and Comparator Output Transient Response Hysteresis Hysteresis can be added to the LTC1440 by connecting a resistor R1 between the REF and HYST pins and a second resistor R2 from HYST to V Figure 4 The difference between the upper and lower threshold voltages or hysteresis voltage band Vyp is equal to twice the voltage difference between the REF and HYST pins When more hysteresis is added the upper threshold increases the same amount as the low threshold de creases The maximum voltage allowed between REF and HYST pins is 50mV producing a maximum hysteresis voltage band of 100mV The hysteresis band could vary by up to 15 If hysteresis is not wanted the HYST pin should be shorted to REF Acceptable values for Iper range from 0 1uA to SuA If 2 4M is chosen for R2 then the value of R1 is equal to the value of Vhp 2 IREF 5 hiex vs HYST R2 7 1440 1 2 04 Figure 4 Programmable Hysteresis Level Detector 1701440 is ideal for use as
3. D LTC 1440 LTC 1441 LTC 1442 TECHNOLOGY Ultralow Power Single Dual Comparator with Reference FEATURES DESCRIPTION Ultralow Quiescent Current 2 1uA LTC1440 LTC 1440 LTC1441 LTC1442 are ultralow power Reference Output Drives 0 01uF Capacitor single and dual comparators with built in references The Adjustable Hysteresis LTC1440 LTC1442 comparators feature less than 3 7uA supply current over Wide Supply Range temperature LTC1440 a 1 182V 1 reference pro Single 2V to 11V grammable hysteresis LTC1440 LTC1 442 and TTL CMOS Dual 1V to 5 5V outputs that sink and source current The reference output m Input Voltage Range Includes the Negative Supply can drive a bypass capacitor of up to 0 01uF without TTL CMOS Compatible Outputs oscillation Prop om Delay with 10mV Overdrive The comparators operate from a single 2V to 11V supply Pan n ice PM or dual 1V to 5 5V supply LTC1440 Comparator Pin Compatible Uparades for MAX921 922 923 hysteresis is easily programmed by using two resistors Lin AN Parkado Erin andthe HYST pin LTC1440 LTC1442 Each comparator s A ackage input operates from the negative supply to within 1 3V of APPLICATIONS the positive supply The comparator output stage can continuously source up to 40mA By eliminating the m Battery Powered System Monitoring cross conducting currentthat normally happens when the Threshold Detectors comparator changes logic
4. with Adjustable Hysteresis LTC1998 1 2 Reference with Comparator with Adjustable Thesholds Li Ion Low Battery Monitor 50723 1 Accuracy LT6700 1 0 4 Reference with Low Voltage Dual Comparators SOT23 1 4V to 18 5V Supply Range 2 Over Temperature LT6700 2 LT6700 3 C Load is a trademark of Linear Technology Corporation 144012fb Linear Technology Corporation LT LWI LT 0605 REV B PRINTED IN USA 1 1630 McCarthy Blvd Milpitas CA 95035 7417 e dares 408 432 1900 FAX 408 434 0507 www linear com LINEAR TECHNOLOGY CORPORATION 1996
5. 2 DRAWING NOT TO SCALE 3 ALL DIMENSIONS ARE IN MILLIMETERS 4 DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH MOLD FLASH IF PRESENT SHALL NOT EXCEED 0 15mm ON ANY SIDE 5 EXPOSED PAD SHALL BE SOLDER PLATED 6 SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON TOP AND BOTTOM OF PACKAGE MS8 Package 8 Lead Plastic MSOP Reference LTC DWG 05 08 1660 0 889 0 127 035 005 206 320 um 45 T rs 136 Dl 3 00 0 102 118 004 uu 052 0 42 0 038 0 65 NOTE 3 8765 0205 01655 015 0256 REF TYP BSC RECOMMENDED SOLDER PAD LAYOUT 3 00 0 102 4 90 0 152 DETAIL A 118 004 193 006 0 254 NOTE 4 T 0 T TYP GAUGE PLANE Y 1221 E 53 0152 021 006 110 oe 043 034 DETAIL REF 0 18 E Sond SEATING Tr PLANE 022 038 0127 0 076 009 015 005 003 NOTE 0256 MSOP 58 0204 1 DIMENSIONS IN MILLIMETER INCH E 2 DRAWING NOT TO SCALE 3 DIMENSION DOES NOT INCLUDE MOLD FLASH PROTRUSIONS OR GATE BURRS MOLD FLASH PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0 152mm 006 PER SIDE 4 DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0 152mm 006 PER SIDE 5 LEAD COPLANARITY BOTTOM OF LEADS AFTER FORMING SHALL BE 0 102mm
6. Add Lead Free Add PBF Lead Free Tape and Reel Add TRPBF Lead Free Part Marking http www linear com leadfree Consult LTC Marketing for parts specified with wider operating temperature ranges The temperature grade is identified by a label on the shipping container 1440120 2 LTC 1440 LTC 1441 LTC 1442 ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range otherwise specifications are at T 25 C V 5V and V GND OV unless otherwise noted SYMBOL PARAMETER CONDITIONS MIN TYP UNITS Power Supply Supply Voltage Range 2 0 11 0 lec Supply Current IN 80mV LTC1440 CTemp Range e 2 1 4 0 uA HYST REF LTC1440 LTC1442 Temp Range 4 4 1761441 3 5 5 7 1761442 3 5 5 7 Comparator Vos Comparator Input Offset Voltage Voy 2 5V 3 10 mV lin Input Leakage Current IN IN 2 5V 0 01 1 0 Input Leakage Current HYST 0 02 1 0 Comparator Input V V 1 3V V Mode Range CMRR Common Mode Rejection Ratio V to V 1 3V 0 1 1 mV V PSRR Power Supply Rejection Ratio V 2V to 11V LTC1441 0 1 1 mV V V 2 2 5V to 11V LTC1440 LTC1442 0 1 1 mV V NOISE Voltage Noise 100Hz to 100kHz 100 uVems Vuyst Hysteresis Input Voltage Range LTC1440 LTC1442 e
7. IN A Pin 3 Noninverting Input of Comparator A Input common mode range from V to V 1 3V Input current typically 10pA at 25 C A Pin 4 Inverting Input of Comparator A Input common mode range from to V 1 3V Input current typically 10pA at 25 LTC1441 OUT B 8 1 OUTA 1701442 X OUTB 8 Mt 6 BJ 5 5 1440 1 2 PD Pin 5 Inverting Input of Comparator Input common mode range from to V 1 3V Input current typically 10pA at 25 C IN B Pin 6 Noninverting Input of Comparator B Input common mode range from to V 1 3V Input current typically 10pA at 25 V Pin 7 Positive Supply 2V to 11V OUT B Pin 8 Comparator B CMOS Output Swings from V to V Output can source to 40mA and sink 5mA LTC1442 OUT A Pin 1 Comparator A CMOS Output Swings from V to V Output can source up to 40mA and sink 5mA V Pin 2 Negative Supply IN A Pin 3 Noninverting Input of Comparator A Input common mode range from to V 1 3V Input current typically 10pA at 25 C Pin 4 Inverting Input of Comparator B Input common mode range from to V 1 3V Input current typically 10pA at 25 C HYST Pin 5 Hysteresis Input Connect to REF if not used Input voltage range is from Vggr to 50mV REF Pin 6 Reference Output 1 182V with respect to V7 Can source up to 200uA and sink 15uA at 25 Drive 0 01uF bypass capacit
8. REF 50mV REF V Propagation Delay Cour 100pF Overdrive 10mV 15 us Overdrive 100mV 8 us Vou Output High Voltage lg 13mA V 04V VoL Output Low Voltage lg 1 8mA LTC1440 e GND 0 4V V LTC1441 LTC1442 e V 0 4V Reference VREF Reference Voltage No Load C Temp Range 1 170 1 182 1 194 LTC1440 LTC1442 Temp Range 1164 1 200 1761440 MSOP DFN 1 164 1 200 Reference Output Source Current AVper lt 1mV 1701442 100 200 Isink Reference Output Sink Current AVper lt 2 5mV 1701442 10 20 pA AVper Reference Source Current 0 lt Isqurce 2mA LTC1440 e 0 8 5 mV Reference Sink Current 0 Isinx lt 10 LTC1440 0 5 1 5 mV 5 NOISE Voltage Noise 100Hz to 100kHz 100 UVRMS 144012fb 3 LIC 1440 LTC 1441 LTC 1442 ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range otherwise specifications are at T 25 V 3V and V GND OV unless otherwise noted SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Power Supply Supply Voltage Range 2 11 lec Supply Current IN INT 80mV LTC1440 CTemp Range e 2 3 9 HYST REF LTC1440 LTC1442 Temp Range 4 3 1761441 3 5 5 7 1761442 3 5 5 7 Comparator Vos Comparator Input Offset Voltage Vem
9. 004 MAX 144012fb LTC 1440 LTC 1441 LTC 1442 PACKAGE DESCRIPTION 8 Package 8 Lead PDIP Narrow 0 300 LTC DWG 05 08 1510 400 10 160 MAX 255 015 6 477 0 381 300 325 045 065 1130 005 7 620 8 255 1 143 1 651 3 302 0 127 o5 1 651 008 415 1 y r 0 203 0 381 120 3 048 020 325 035 MIN 0508 EPI joo 018x009 TU ass 5 0 457 0 076 NOTE INCHES 1 DIMENSIONS ARE MILLIMETERS 5 DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 010 INCH 0 254mm 8 Package 8 Lead Plastic Small Outline Narrow 0 150 LTC DWG 05 08 1610 045 MH H NOTE 3 ex 8 7 6 5 X 245 MIN x al 157 eee 3 810 3 988 01 IB 5 701 6 197 NOTER 030 4 005 gt TYP Y RECOMMENDED SOLDER PAD LAYOUT 010 020 0 254 0 508 053 069 1 346 1 752 004 010 008 010 0203 0254 0 TYP x 0 101 0 254 0254 m A ee t 014 019 1 w 0 355 0 483 1270 NOTE 5 BSC INCHE 1 DIMENSIONS IN MILLIMETERS 2 DRAWING NOT TO SCALE 3 THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS x 45 MOLD F
10. 1 160 1 175 1 155 1 170 0 05 10 15 20 25 30 35 0 5 10 15 20 25 30 OUTPUT LOAD CURRENT mA OUTPUT LOAD CURRENT uA 1440 1 2 G11 1440 1 2 G12 Reference Voltage vs Temperature 1 186 1 184 amp 1 182 1 180 5 2 1 178 g 1176 ce 1 174 1472 1 170 60 40 20 0 20 40 60 80 100 120 140 TEMPERATURE C 1440 1 2 G13 144012fb LTC 1440 LTC 1441 LTC 1442 PIN FUNCTIONS 1 OUTA LTC1440 GND Pin 1 Ground Connect to V for single supply operation V Pin 2 Negative Supply Connect to ground for single supply operation Potential should be more negative than GND IN Pin 3 Noninverting Comparator Input Input com mon mode range from V to V 1 3V Input current typically 10pA at 25 Pin 4 Inverting Comparator Input Input common mode range from V to V 1 3V Input current typically 10pA at 25 C HYST Pin 5 Hysteresis Input Connect to REF if not used Input voltage range is from Vggr 0 REF Pin 6 Reference Output 1 182 with respect to V7 Can source up to 200uA and sink 15uA at 25 Drive 0 01uF bypass capacitor without oscillation V Pin 7 Positive Supply 2V to 11V OUT Pin 8 Comparator CMOS Output Swings from GND to V Output can source up to 40mA and sink 5mA LTC1441 OUT A Pin 1 Comparator A CMOS Output Swings from V to V Output can source up to 40mA and sink 5mA V Pin 2 Negative Supply
11. 1 5V 3 10 lin Input Leakage Current IN INT Viy Vin7 1 5V 0 01 1 Input Leakage Current HYST 0 02 1 Comparator Input Common V V 1 3V V Mode Range CMRR Common Mode Rejection Ratio to V 1 3V 0 1 1 PSRR Power Supply Rejection Ratio V 2V to 11V LTC1441 0 1 1 mV V V 2 2 5V to 11V LTC1440 LTC1442 0 1 1 mV V NOISE Voltage Noise 100Hz to 100kHz 100 UVRMS Vuyst Hysteresis Input Voltage Range LTC1440 LTC1442 e REF 50mV REF V tpp Propagation Delay Cour 100pF Overdrive 10mV 14 ys Overdrive 100mV 5 us Vou Output High Voltage 8mA e Vt 0 4V Comparator VoL Output Low Voltage lp 0 8mA LTC1440 e GND 0 4V LTC1441 LTC1442 e V 04V V Reference VREF Reference Voltage No Load C Temp Range 1 170 1 182 1 194 LTC1440 LTC1442 Temp Range e 1 164 1 200 V LTC1440 MSOP DFN e 1 164 1 200 V Isource Reference Output Source Current lt 1mV LTC1442 60 120 Isink Reference Output Sink Current AVper lt 2 5mV 1701442 10 20 uA AVner Reference Source Current 0 IsoyncE 1mA LTC1440 e 0 8 5 5 mV Reference Sink Current 0 Isiyk 10 LTC1440 0 5 1 5 mV 5 NOISE Voltage Noise 100Hz to 100kHz 100 Note 1 Absolute Maximum Ratings those values beyond which the life of a device may be impaired 144012fb LTC 1440 LTC 1441 LTC 1442 TYPICAL PERFORMANCE CHARACTERISTICS
12. states the power supply glitches Window Comparators are eliminated m Oscillator Circuits The LTC1440 is available in 8 pin PDIP SO MSOP and DFN packages The LTC1441 LTC1442 are available in 8 pin PDIP and SO packages TYPICAL APPLICATION Micropower 2 9V Vcc Threshold Detector A LTC1440 Supply Current vs Temperature 5 0 V 5V 45 V GND 0V gt o SUPPLY CURRENT uA LTC1440 1 5 40 20 0 20 40 60 80 100 TEMPERATURE C 1440 1 2 TA02 1440 01 1440129 LI MYR 1 LIC 1440 LTC 1441 LTC 1442 ABSOLUTE MAXIMUM RATINGS Note 1 Voltage OUT Short Circuit Duration V lt 5 5V Continuous V to V V to GND GND to V 12Vto 0 3V Power 500mW IN INT V 0 3V to V 0 3V Operating Temperature Range REF V 0 3V to V 0 3V 0 C to 70 C OUT LTC1440 V 0 3V to GND 0 3V 4090 to 85 C OUT LTC1441 LTC1442 0 3V to V 0 3V Storage Temperature Range 65 C to 150 C Current Storage Temperature Range HYS 20 DD 65 to 125 C
13. LASH OR PROTRUSIONS SHALL NOT EXCEED 006 0 15mm 08 0303 144012fb Information furnished by Linear Technology Corporation is believed to be accurate and reliable y LI TAR However no responsibility is assumed for its use Linear Technology Corporation makes no represen 1 TECHNOLOGY tation that the interconnection of its circuits as described herein will not infringe on existing patent rights LIC 1440 LTC 1441 LTC 1442 TYPICAL APPLICATION 10kHz V F Converter V 6 2V TO 12V Q8 LT1034 1 2 10kHz TRIM 200k INPUT 12 LT1034 1 2 OV TO 5V 2M TYP 100Hz TRIM pf HP5082 2810 P 1N4148 2N2222 1 METAL FILM POLYSTYRENE four OkHz TO 10kHz 1440 1 2 TA04 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC1443 1 182V Reference with Micropower Quad Comparators 1 Accuracy 8 5 Maximum Current Ref Output Drives 0 01uF LTC1444 LTC1445 1 2V Reference with Quad Comparator 1 Accuracy 8 5uA Maximum Current Ref Output Drives 0 01 uF with Adjustable Hysteresis LTC1540 1 182V Reference with Nanopower Comparator DFN Package 0 3uA Quiescent Current Typical Reference with Adjustable Hysteresis Drives 0 01 uF 1101541 1 2V Reference with Micropower Amplifier and Comparator DFN Package 1 25 Accuracy Rail to Rail Out Low Offset Amplifier LTC1842 LTC1843 1 82V Reference with Dual Comparators 1 Accuracy Open Drain Out Reference Drives 0 01
14. UPPLY VOLTAGE V 1440 1 2 G05 1440 1 2 606 Comparator Output Voltage High vs Load Current OUTPUT VOLTAGE HIGH V 0 10 20 30 40 50 60 LOAD CURRENT mA 1440 1 2 607 144012fb LTC 1440 LTC 1441 LTC 1442 TYPICAL PERFORMANCE CHARACTERISTICS Comparator Output Voltage Low LTC1440 LTC1442 vs Load Current Hysteresis Control 2 5 80 Ta 25 C 60 2 0 lt V 3V 40 gt Vt 2V 90 1 5 E V 51 TED 1 0 20 a 5 2 40 0 5 60 3 0 80 0 10 20 30 40 50 60 70 80 0 10 20 30 40 50 LOAD CURRENT mA Vngr mV 1440 1 2 608 LTC1440 Supply Current vs Temperature SUPPLY CURRENT 1 60 40 20 0 20 40 60 80 100 120 140 TEMPERATURE C 1440 1 2 G10 1440 1 2 609 144012fb 7 LIC 1440 LTC 1441 LTC 1442 TYPICAL PERFORMANCE CHARACTERISTICS Reference Output Voltage vs Reference Output Voltage vs Output Load Current Output Load Current Sink 1 190 1 200 Vec 5V Veo 2V amp 1185 1 195 8 SOURCE E Voc 5V 3 5 1190 1 175 E 1 185 m E SINE amp 1 165 amp amp
15. a micropower level detector as shown in Figure 5 R1 and R2 form a voltage divider from to the noninverting comparator input and R4 set the hysteresis voltage and R5 and C1 bypass the reference output The following design procedure can be used to select the component values 1 Choose the Vj voltage trip level in this example 4 65V 1440 1 2 F05 Figure 5 Glitch Free Level Detector with Hysteresis 144012fb 11 LIC 1440 LTC 1441 LTC 1442 APPLICATIONS INFORMATION 2 Calculate the required resistive divider ratio Ratio Vper V Rati M 65V 0 254 MEC V di 3 Choose the required hysteresis voltage band at the 2 input Vugiy inthis example 60mV Calculate the hyster R2 3 40M esis voltage band referred to the comparator input Vu Vhen Ratio Low Voltage Operation 60mV 0 254 The guaranteed minimum operating voltage is 2V or 1V As the total supply voltage is reduced below 2V the 15 24mV performance degrades and the supply current falls Both A Choose the values for and R4 to set the hysteresis the reference and the comparator are still functioning with supply voltage down to 1 5V The reference will have R4 2 4M slightly worse temperature coefficient While the com Vug 15k parator would have less output drive and the propagation delay increases The useful input voltage range extends from the negative sup
16. er 20mA Junction 150 C QU v 90mA X Junction Temperature DD Package 125 C Lead Temperature Soldering 10 sec 300 C PACKAGE ORDER INFORMATION TOP VIEW TOP VIEW GND 1 8 OUT TOP VIEW vE 7 vt EE sd IN 3 6 REF IN 3 6 REF IN 4 5 HYST 58 PACKAGE DD PACKAGE 8 PACKAGE S8 PACKAGE 8 LEAD PLASTIC MSOP 8 LEAD 3mm x 3mm PLASTIC DFN 8 LEAD PDIP 8 PLASTIC SO 150 C 0j4 250 C W Tymax 125 C 160 C W DD 150 C Oya 130 C W 8 UNDERSIDE METAL CONNECTED TO V Tmax 150 C 175 C W 58 PCB CONNECTION OPTIONAL ORDER PART DD8 PART ORDER PART 58 PART ORDER PART MS8 PART NUMBER MARKING NUMBER MARKING NUMBER MARKING LTC1440CDD LBTH LTC1440CN8 1440 LTC1440CMS8 LTBX LTC1440IDD 17014400658 14401 LTC14401MS8 LTC14401N8 LTC14401S8 ORDER PART ORDER PART TOP VIEW NUMBER TOP VIEW NUMBER OUTA 1 8 OUTB LTC1441CN8 OUT A 1 8 OUT B LTC1442CN8 v 2 7 v LTC1441CS8 v 7 v 17014420658 INA 3 6 IN B LTC14411N8 IN A 3 6 REF LTC14421N8 INA 4 5 INB LTC14411S8 IN B 4 5 HYST LTC1442188 N8 PACKAGE 8 PACKAGE 58 PART 8 PACKAGE 58 PACKAGE 58 PART 8 LEAD PDIP 8 LEAD PLASTIC SO MARKING 8 LEAD PDIP 8 LEAD PLASTIC SO MARKING Tyce 89 e 175 0 W 58 1441 Tht 180 1720 W 8 1442 14411 14421 Order Options Tape and Reel
17. or without oscillation V Pin 7 Positive Supply 2V to 11V OUT B Pin 8 Comparator B CMOS Output Swings from V to V Output can source to 40mA and sink 5mA 1440120 9 LIC 1440 LTC 1441 LTC 1442 APPLICATIONS INFORMATION LTC1440 LTC1441 LTC1442 are family of micropower comparators with built in 1 182V reference Features include programmable hysteresis LTC1440 LTC1442 wide supply voltage range 2V to 11V and the ability ofthe reference to drive up to a 0 01uF capacitor without oscil lation The comparators CMOS outputs can source up to 40mA and the supply current glitches that normally occur when switching logic states have been eliminated Power Supplies The comparator family operates from a single 2V to 11V supply The LTC1440 includes a separate ground for the comparator output stage allowing a split supply ranging from 1Vto 5 5V Connecting V to GND onthe LTC1440 will allow single supply operation If the comparator out put is required to source more than 1mA or the supply source impedance is high V should be bypassed with a 0 1uF capacitor Comparator Inputs The comparator inputs can swing from the negative sup ply V to within 1 3V max of the positive supply Vt The inputs can be forced 300mV below V or above V without damage and the typical input leakage current is only 10 Comparator Outputs The 1701440 comparator output swings between GND and V to a
18. ply to a little under 1V below the positive supply which is slightly closer to the positive rail 1 18M than the device operating from higher supply voltages Choose the values for R1 and R2 to set the trip point gr Maer _ 1 182V lgas 144012fb 12 LT Wee LTC 1440 LTC 1441 LTC 1442 TYPICAL APPLICATIONS 10 Bit 3014 A D Converter 1M 5V 470k 5V EIN OV TO 3V 1171034 100k 1 2V 10pF 365k VN2222LL CONV TRW IRC MRT 5 120ppm C COMMAND Low Battery Detect Operates Down to 1 5V OUT 1440 06 32 768kHz STATUS DATA 74c00 Jo 4 74c00 099 our 74C74 CLK 1440 1 2 TA03 32 768kHz Watch Crystal Oscillator 1M 32 768kHz 1440 1 2 TAOS 144012fb 13 LIC 1440 LTC 1441 LTC 1442 PACKAGE DESCRIPTION DD Package 8 Lead Plastic DFN 3mm x 3mm Reference LTC DWG 05 08 1698 Y HOOD 3 5 0 05 2 15 0 05 2 SIDES a PACKAGE HUG OUTLINE y 1 0 25 0 054 gt lt 0 50 BSC I 2 38 0 05 gt 2 SIDES RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 0 38 0 10 i x 3002010 1655040 4SIDES 2 SIDES PIN 1 MARK O Y 0 0 75 0 05 bs lt 0 50 BSC A I 2 38 0 10 gt 2 SIDES BOTTOM VIEW EXPOSED PAD US 1 DRAWING TO BE MADE A PACKAGE OUTLINE M0 229 VARIATION OF WEED 1
19. ssure TTL compatibility with a split supply The LTC1441 and LTC1442 outputs swing between V and V The outputs are capable of sourcing up to 40mA and sinking up to 5mA while still maintaining microampere quiescent currents The output stage does not generate crowbar switching currents during transitions which helps minimize parasitic feedback through the supply pins Voltage Reference The internal bandgap reference has a voltage of 1 182V referenced to V The reference accuracy is 1 5 from 40 C to 85 C It can source up to 200uA and sink up to 20uA with a 5V supply The reference can drive a bypass capacitor of up to 0 01uF without oscillation and by inserting a series resistor capacitance values up to 100uF can be used Figure 1 Figure 2 shows the resistor value required for different capacitor values to achieve critical damping Bypassing the reference can help prevent false tripping of the com parators by preventing glitches on V or reference load transients from disturbing the reference output voltage Figure 3 shows the bypassed reference output with a square wave applied to the V pin Resistors R2 and R3 set 10mV of hysteresis voltage band while R1 damps the reference response Note that the comparator output doesn t trip REFERENCE OUTPUT 1440 1 2 F01 Figure 1 Damping the Reference Output 1000 100 RESISTOR VALUE

LINEAR TECHNOLOGY LTC1440/LTC1441/LTC1442 handbook

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