LTC2991IMS#PBF Linear Technology, LTC2991IMS#PBF Datasheet

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... L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Easy Drive is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...

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... LEAD FREE FINISH TAPE AND REEL LTC2991CMS#PBF LTC2991CMS#TRPBF LTC2991IMS#PBF LTC2991IMS#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Differential Voltage Common Mode Range DIFF(CMR) V Differential Voltage LSB Weight LSB(DIFF) V Single-Ended Voltage LSB Weight LSB(SINGLE_ENDED) V Temperature LSB Weight LSB(TEMP) V Diode Voltage LSB Weight ...

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LTC2991 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER Timing (Note 2) f Maximum SCL Clock Frequency SCL(MAX) t Minimum SCL Low Period LOW t Minimum SCL High Period HIGH t Minimum Bus Free ...

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TYPICAL PERFORMANCE CHARACTERISTICS Shutdown Current vs Temperature 3.5 3 2.5 2.0 1 3.3V CC 1.0 0.5 0 –50 – 100 125 T (°C) AMB 2991 G01 V TUE CC 0.25 ...

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LTC2991 TYPICAL PERFORMANCE CHARACTERISTICS Single-Ended Noise 4000 4800 READINGS 3500 3000 2500 2000 1500 1000 500 0 –3 –2 – LSBs (305.18μV/LSB) 2991 G10 LTC2991 Differential Noise 500 800 READINGS 400 300 200 100 0 –4 ...

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TYPICAL PERFORMANCE CHARACTERISTICS Digital Filter Step Response 100 100 50 150 ITERATION 2991 G18 ERROR SERIES 100 10 1 0.1 200 0 1000 2000 3000 4000 ...

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LTC2991 PIN FUNCTIONS V1 (Pin 1): First Monitor Input. This pin can be configured as a single-ended input (0V to 4.9V) or the positive input for a differential or remote diode temperature measurement (in combination with V2). Differential common mode ...

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FUNCTIONAL DIAGRAM V VOLTAGE MONITORING V1 – – SENSE – L POWER V6 MONITORING REMOTE V8 DIODE 8 SENSORS ...

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LTC2991 TIMING DIAGRAM SDAI/SDAO SCL t HD, STA START CONDITION SU, DAT SU, STA HD, DATO, t HD, STA t HD, DATI REPEATED START CONDITION BUF t SU, STO t SP 2991 TD ...

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OPERATION The LTC2991 monitors voltage, current, internal and remote temperatures. It can be configured through an I face to measure many combinations of these parameters. Single or repeated measurements can be configured. Remote temperature measurements use transistors as temperature sensors, ...

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LTC2991 APPLICATIONS INFORMATION The basic LTC2991 application circuit is shown in Figure 1. 5V 3.3V 2.5V R SENSE 1. SDA SCL LTC2991 2-WIRE ADR0 INTERFACE ADR1 ADR2 T AMBIENT PWM GND ...

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APPLICATIONS INFORMATION Compensated Kelvin temperature: η = CAL COMP K _ MEAS η ACT Compensated Celsius temperature: ( η CAL 273. η C COMP C MEAS ACT A 16-bit unsigned ...

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LTC2991 APPLICATIONS INFORMATION In the case of current measurements, the external sense resistor is typically small, and determined by the full-scale input voltage of the LTC2991. The full-scale differential voltage is 0.300V. The external sense resistance, is then a function ...

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APPLICATIONS INFORMATION changes in temperature using the approximate relation- ship of –2.1mV/°C of voltage dependence on temperature. With an LSB weight of 38.15μV and a diode temperature relationship of –2.1mV/°C this yields ~0.018 degree resolu- tion. For sensor applications involving ...

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LTC2991 APPLICATIONS INFORMATION below the PWM Threshold, the PWM output pin will be a constant logic level 0. For temperatures 32 degrees above the PWM Threshold, the PWM output pin will be a constant logic level 1. This relationship is ...

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APPLICATIONS INFORMATION it remains LOW during this pulse to acknowledge receipt of the data. If the slave fails to acknowledge by leaving SDA HIGH, then the master can abort the transmission by generating a STOP condition. After the master has ...

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LTC2991 APPLICATIONS INFORMATION Figure 6. LTC2991 Serial Bus Repeated Write Byte Protocol S ADDRESS 1001 1a1:a0 S ADDRESS 1001 1a1:a0 Figure 8. LTC2991 Serial Bus Repeated Read Byte Protocol 2 Table Base Address BASE ...

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APPLICATIONS INFORMATION Table 2. LTC2991 Register Address and Contents REGISTER † ADDRESS* REGISTER NAME 00h STATUS LOW 01h CH EN, STAT. HI, TRIGGER** 02h Reserved 03h Reserved 04h Reserved 05h Reserved 06h V1, V2 and V3, V4 CONTROL 07h V5, ...

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LTC2991 APPLICATIONS INFORMATION Table 3. STATUS LOW (00h) Register BIT NAME b7 V8, T4, V7 – V8 Ready b6 V7, T4, V7 – V8 Ready b5 V6, T3, V5 – V6 Ready b4 V5, T3, V5 – V6 Ready b3 ...

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APPLICATIONS INFORMATION Table 6. V5, V6 and V7, V8 CONTROL (07h) Register (Default 00h) BIT NAME b7 V7, V8 Filt b6 T Kelvin R4 b5 V7, V8 Temperature b4 V7, V8 Differential b3 V5, V6 Filt b2 T Kelvin R3 ...

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LTC2991 APPLICATIONS INFORMATION Table 11. Temperature Measurement MSB Data Register Format Bit7 Bit6 Bit5 Bit4 DV D12 *Data valid is set when a new result is written into the register. Data valid is cleared when this register is ...

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APPLICATIONS INFORMATION Table 16. Conversion Formats TEMPERATURE FORMATS Temperature Internal, T Through LSB = 0.0625 Degrees Diode Voltage Formats Remote Temperature T Through LSB = 38.15μV Table 17. Recommended Transistors to Be Used as ...

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LTC2991 TYPICAL APPLICATIONS I LOAD 0A TO 10A 24 High Voltage/Current and Temperature Monitoring 1mΩ R SENSE = 20Ω 1% –INF +IN –INS + – – REG OUT LTC6102HV R 200k 4.99k 1% ...

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TYPICAL APPLICATIONS MOTOR CONTROL VOLTAGE Computer Voltage and Temperature Monitoring 12V 5V 3.3V 10k 30. 0.1μF 10k 10k 1% 1% MICROPROCESSOR 2-WIRE I C SDA V3 INTERFACE LTC2991 SCL ADR0 ADR1 V4 ADR2 ...

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LTC2991 TYPICAL APPLICATIONS MOTOR CONTROL VOLTAGE 3. 2-WIRE I C SDA INTERFACE LTC2991 SCL ADR0 ADR1 GND T AMBIENT CONTROL REGISTER 0x06 = 0xAA T AMBIENT T FAN1 T FAN2 Large Motor Protection/Regulation ...

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TYPICAL APPLICATIONS BATTERY I AND V MONITOR CHARGING CURRENT 2-WIRE I C SDA INTERFACE LTC2991 SCL ADR0 ADR1 ADR2 GND T AMBIENT VOLTAGE AND TEMPERATURE CONFIGURATION: CONTROL REGISTER: 0xA1 T AMBIENT V BAT I BAT ...

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LTC2991 TYPICAL APPLICATIONS 3. SDA μC LTC2991 SCL ADR0 ADR1 ADR2 GND OTHER APPS CONTROL REGISTER 0x06 = 0xAA T REG 1A, 1B: 0.0625°C/LSB AMBIENT T REG 0A, 0B: 0.0625°C/LSB DRY T REG 0C, 0D: ...

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TYPICAL APPLICATIONS 2-WIRE INTERFACE VOLTAGE, CURRENT, TEMPERATURE AND PWM CONFIGURATION: CONTROL REGISTER PWM INTERNAL CC PWM REGISTER T REG 1A, 1B AMBIENT V REG 0A, 0B HEATER I REG 0C, 0D HEATER T REG ...

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LTC2991 TYPICAL APPLICATIONS QUAD Remote Temperature Sensing with Two Wire Pairs Using One LTC2991 Channel 3. LTC2991 SDA SCL GND SDA SCL CROSS-POINT SWITCH LTC2991 CONTROL REGISTER 0x06 0xAA LTC1393 CONTROL BYTE SENSOR A = 0x0B LTC1393 CONTROL ...

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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... Can Be Used as Linear Temperature Sensor ● www.linear.com REG 1A, 1B: 0.0625°C/LSB REG 0A, 0B: 305μV/LSB REG 0C, 0D: 194μA/LSB REG 1A, 1B: 0.0625°C/LSB REG 1C, 1D: 2.5V + 305.18μV/LSB 2 C Interface LT 0811 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORA TION 2011 2991f ...