LM75BD,112 NXP Semiconductors, LM75BD,112 Datasheet
LM75BD,112
Specifications of LM75BD,112
LM75BD
LM75BD
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LM75BD,112 Summary of contents
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LM75B Digital temperature sensor and thermal watchdog Rev. 02 — 9 December 2008 1. General description The LM75B is a temperature-to-digital converter using an on-chip band gap temperature sensor and Sigma-Delta A-to-D conversion technique with an overtemperature detection output. The ...
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... NXP Semiconductors I Frequency range 400 kHz with bus fault time-out to prevent hanging up the bus I 11-bit ADC that offers a temperature resolution of 0.125 C I Temperature accuracy of Programmable temperature threshold and hysteresis set points I Supply current of 1 shutdown mode for power conservation I Stand-alone operation as thermostat at power-up ...
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... NXP Semiconductors 5. Block diagram LM75B Fig 1. 6. Pinning information 6.1 Pinning Fig 2. Fig 4. LM75B_2 Product data sheet Digital temperature sensor and thermal watchdog BIAS REFERENCE BAND GAP 11-BIT TEMP SENSOR SIGMA-DELTA A-to-D CONVERTER OSCILLATOR POWER-ON RESET LOGIC CONTROL AND INTERFACE A2 A1 ...
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... NXP Semiconductors 6.2 Pin description Table 2. Symbol SDA SCL OS GND Functional description 7.1 General operation The LM75B uses the on-chip band gap sensor to measure the device temperature with the resolution of 0.125 C and stores the 11-bit 2's complement digital data, resulted from 11-bit A-to-D conversion, into the device Temp register ...
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... NXP Semiconductors In OS comparator mode, the OS output behaves like a thermostat. It becomes active when the Temp exceeds the T Reading the device registers or putting the device into shutdown does not change the state of the OS output. The OS output in this case can be used to control cooling fans or thermal switches ...
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... NXP Semiconductors 2 7.2 I C-bus serial interface The LM75B can be connected to a compatible 2-wire serial interface I device under the control of a controller or master device, using two device terminals, SCL and SDA. The controller must provide the SCL clock signal and write/read data to/from the device through the SDA terminal ...
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... NXP Semiconductors 7.4.1 Pointer register The Pointer register contains an 8-bit data byte, of which the two LSB bits represent the pointer value of the other four registers, and the other 6 MSB bits are equal shown in Table 5 select the data register for write/read operation by including the pointer data byte in the bus command ...
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... NXP Semiconductors Table 7. Legend default value. Bit B1 B0 7.4.3 Temperature register The Temperature register (Temp) holds the digital result of temperature measurement or monitor at the end of each analog-to-digital conversion. This register is read-only and contains two 8-bit data bytes consisting of one Most Significant Byte (MSByte) and one Least Signifi ...
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... NXP Semiconductors Table 9. 11-bit binary (2’s complement) 111 0011 1000 110 0100 1001 110 0100 1000 For 9-bit Temp data application in replacing the industry standard LM75, just use only 9 MSB bits of the two bytes and disregard 7 LSB of the LSByte. The 9-bit Temp data with 0.5 C resolution of the LM75B is defi ...
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... NXP Semiconductors Table 12. 11-bit binary (2’s complement) 0 1111 1010 0 0011 0010 0 0000 0001 0 0000 0000 1 1111 1111 1 1100 1110 1 1001 0010 7.5 OS output and polarity The OS output is an open-drain output and its state represents results of the device watchdog operation as described in external pull-up resistor is needed. The resistor should be as large as possible 200 minimize the Temp reading error due to internal heating by the high OS sinking current ...
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... NXP Semiconductors 7.7 OS fault queue Fault queue is defined as the number of faults that must occur consecutively to activate the OS output provided to avoid false tripping due to noise. Because faults are determined at the end of data conversions, fault queue is also defined as the number of consecutive conversions returning a temperature trip. The value of fault queue is selectable by programming the two bits B4 and B3 (OS_F_QUE[1:0]) in register Conf ...
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... NXP Semiconductors 7.10 Protocols for writing and reading the registers The communication between the host and the LM75B must strictly follow the rules as defined by the I operations are illustrated in 1. Before a communication, the I and SDA lines must both be released by all devices on the bus, and they become HIGH by the bus pull-up resistors ...
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... NXP Semiconductors SCL SDA device address START acknowledge Fig 6. Write configuration register (1-byte data SCL SDA device address START 1 2 SCL (cont.) SDA (cont device address Fig 7. Read configuration register including pointer byte (1-byte data SCL SDA START Fig 8. ...
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... NXP Semiconductors 1 SCL SDA S 1 START 1 SCL (cont.) SDA (cont.) D7 Fig 9. Write Tos or Thyst register (2-byte data SCL SDA device address START SCL (cont) SDA (cont device address Fig 10. Read Temp, Tos or Thyst register including pointer byte (2-byte data SCL SDA ...
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... NXP Semiconductors 8. Application design-in information 8.1 Typical application Fig 12. Typical application 8.2 LM75A and LM75B comparison Table 14. LM75A and LM75B comparison Description availability of the XSON8U ( output auto-reset when SHUTDOWN bit is set in interrupt mode support single-byte reading of the Temp registers without bus lockup ...
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... NXP Semiconductors [5] The LM75B performs the temperature-to-data conversions with a much higher speed than the LM75A. While the LM75A takes almost the whole of conversion period (T about 10 ms. Therefore, the conversion period (T two parts. A shorter conversion time is applied to significantly reduce the device’s average power dissipation. During each conversion period, when the conversion is completed, the LM75B becomes idled and the power is reduced, resulting in a lesser average power consumption ...
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... NXP Semiconductors 9. Limiting values Table 15. In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol O(sink stg T j 10. Recommended operating conditions Table 16. Symbol amb LM75B_2 Product data sheet Digital temperature sensor and thermal watchdog Limiting values Parameter Conditions supply voltage ...
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... NXP Semiconductors 11. Static characteristics Table 17. Static characteristics +125 C; unless otherwise specified. CC amb Symbol Parameter T temperature accuracy acc T temperature resolution res t temperature conversion conv(T) time T conversion period conv I average supply current DD(AV) V HIGH-level input voltage IH V LOW-level input voltage IL V hysteresis of input voltage SCL and SDA pins ...
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... NXP Semiconductors 300 I DD(AV 5 4.5 V 200 3.3 V 2.8 V 100 Fig 13. Average supply current versus temperature C-bus inactive 0.5 I DD(sd 0 0.3 0.2 0 Fig 15. Shutdown mode supply current versus temperature 0.5 V OL(SDA) ( 4.5 V 3.3 V 0.3 2.8 V 0.2 0 Fig 17. LOW-level output voltage on pin SDA versus temperature ...
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... NXP Semiconductors 12. Dynamic characteristics 2 Table 18. I C-bus interface dynamic characteristics +125 C; unless otherwise specified. CC amb Symbol Parameter f SCL clock frequency SCL t HIGH period of the SCL clock HIGH t LOW period of the SCL clock LOW t hold time (repeated) START condition HD;STA ...
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... NXP Semiconductors 13. Package outline SO8: plastic small outline package; 8 leads; body width 3 pin 1 index 1 DIMENSIONS (inch dimensions are derived from the original mm dimensions) A UNIT max. 0.25 1.45 mm 1.75 0.25 0.10 1.25 0.010 0.057 inches 0.069 0.01 0.004 0.049 Notes 1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. ...
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... NXP Semiconductors TSSOP8: plastic thin shrink small outline package; 8 leads; body width pin 1 index 1 e DIMENSIONS (mm are the original dimensions UNIT max. 0.15 0.95 mm 1.1 0.25 0.05 0.80 Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm maximum per side are not included. ...
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... NXP Semiconductors XSON8U: plastic extremely thin small outline package; no leads; 8 terminals; UTLP based; body 0.5 mm terminal 1 index area DIMENSIONS (mm are the original dimensions) A UNIT max 0.05 0.35 2.1 mm 0.5 0.00 0.15 1.9 OUTLINE VERSION IEC SOT996 Fig 22. Package outline SOT996-2 (XSON8U) ...
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... NXP Semiconductors 14. Soldering of SMD packages This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 “Surface mount reflow soldering description” . 14.1 Introduction to soldering Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits ...
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... NXP Semiconductors 14.4 Reflow soldering Key characteristics in reflow soldering are: • Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to higher minimum peak temperatures (see reducing the process window • Solder paste printing issues including smearing, release, and adjusting the process window for a mix of large and small components on one board • ...
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... NXP Semiconductors Fig 23. Temperature profiles for large and small components For further information on temperature profiles, refer to Application Note AN10365 “Surface mount reflow soldering description” . 15. Abbreviations Table 21. Acronym A-to-D CDM ESD HBM 2 I C-bus I/O LSB LSByte MM MSB MSByte ...
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... NXP Semiconductors 16. Revision history Table 22. Revision history Document ID Release date LM75B_2 20081209 • Modifications: added XSON8U package option (affects Section 6.1 LM75B_1 20081204 LM75B_2 Product data sheet Digital temperature sensor and thermal watchdog Data sheet status Product data sheet Section 2 “ ...
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... Right to make changes — NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice ...
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... NXP Semiconductors 19. Contents 1 General description . . . . . . . . . . . . . . . . . . . . . . 1 2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 5 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 6 Pinning information . . . . . . . . . . . . . . . . . . . . . . 3 6.1 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 6.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4 7 Functional description . . . . . . . . . . . . . . . . . . . 4 7.1 General operation . . . . . . . . . . . . . . . . . . . . . . . 4 2 7.2 I C-bus serial interface . . . . . . . . . . . . . . . . . . . 6 7.2.1 Bus fault time-out . . . . . . . . . . . . . . . . . . . . . . . 6 7.3 Slave address . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7 ...