TMP75 UMW | Alldatasheet

Document overview

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Technical content

Features

  • Low-voltage alternative to the TMP75AIDR and

Description

The TMP75 is a fully integrated digital temperature sensor that can work at low voltage (1.8V) and is fully pin and register compatible with NCT75 and ADT75. The TMP75 has a ± 1° C accuracy over the operating temperature range. The on-chip 12-bit analog-to-digital converter (ADC) provides a temperature resolution of 0.0625° C. The TMP75 supports up to 8 devices address and provides an over-temperature alarm function. Based on programmable upper and lower temperature limits and an ALERT pin, the TMP75 can be used as a thermostat or an over-temperature alarm. The TMP75 has been precisely calibrated at the factory, and the user does not need to perform any additional processing on the temperature output. TMP75AIDGKR

  • Operating temperature range : - 55°C ~ +125°C
  • Temperature accuracy : ± 0.5° C (0° C ~ +70° C)
  • Supply voltage range : 1.4V ~ 5.5V
  • Low quiescent current : - Normal mode : 15μA (typ) - Shutdown mode : 1μA (typ)
  • Resolution : 12-bits (0.0625° C)
  • Digital Output : I2C

Applications

  • Portable, battery-powered applications
  • Power-supply temperature monitoring
  • Computer peripheral thermal protection
  • Laptop computers
  • Battery management
  • Office machines
  • Thermostat controls
  • Electro mechanical device temperature
  • General temperature measurement –Industrial control –test equipment –Medical instruments UMW R www.umw-ic.com 1 UTD Semiconductor Co.,Limited

Pin Configuration and Functions Pin Functions PIN NO. NAME 1 SDA Serial data. Open-drain output; requires a pull-up resistor. 2 SCL Serial clock. Open-drain output; requires a pull-up resistor. 3 ALERT Over-temperature alert. Open-drain output; requires a pull-up resistor. 4 GND Ground. 5 A2 Address select. Connect to GND or V+. 6 A1 Address select. Connect to GND or V+. 7 A0 Address select. Connect to GND or V+. 8 V+ Supply voltage, 1.4V~5.5V. 1SDA SCL ALERT GND 8 V+ UMW Rwww.umw-ic.com 2 UTD Semiconductor Co.,Limited MSOP & SOP Package 8-Pin Top View Specifications Absolute Maximum Ratings Over operating free-air temperature range (unless otherwise noted). Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. MIN MAX UNIT Supply Voltage, V+ 6 V Voltage at SCL, SDA, A2, A1 and A0 -0.5 6 V Voltage at ALERT -0.5 ((V+)+0.3) and ≤5.5 V Operating Temperature -55 150 °C Junction Temperature 150 °C Storage Temperature -60 150 °C TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R

Recommended Operating Conditions Over operating free-air temperature range (unless otherwise noted). and ≤4 Value UNIT Electrostatic Discharge Human Body Mode (HBM), per ANSI/ESDA/JEDEC JS-001 ±5000 V Machine Mode (MM), per JEDEC-STD Classification 300 V MIN NOM MAX UNIT Supply Voltage V+ 1.4 1.8 5.5 V Operating Temperature TA - 40 125 °C UMW Rwww.umw-ic.com 3 UTD Semiconductor Co.,Limited

Electrical Characteristics

PARAMETER TEST CONDITONS MIN TYP MAX UNIT Operating Temperature Range -40 125 ° C Temperature Accuracy (Error) Supply Voltage Sensitivity -40° C to +125° C 0.0625 ± 0.25 °C/V Resolution 0.0625 °C

12 Bits

Conversion Time One-Shot Mode 26 35 ms Conversion Rate 12 Conv/s Bus Timeout Time 22 40 ms Communication Frequency Fast-Mode 0.001 0.4 MHz High-speed mode 0.001 2.75 Power Supply Voltage 1.4 1.8 5.5 V Average Quiescent Current, IQ Serial bus inactive 15 37 μA Serial bus inactive, fSCL=400 kHz 25 Serial bus inactive, fSCL=2.75 MHz 95 Shutdown Current, ISD Serial bus inactive 0.5 1 μA Serial bus inactive,fSCL =400 kHz 10 Serial bus inactive,fSCL =2.75 MHz 80 TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R

The 12-bit digital output for each temperature measurement is stored in a read-only temperature sensor. the temperature. If less than 1°C temperature resolution is not required, the user can choose not to read byte 2. and negative numbers are represented in two's complement. conversion is completed. Unused bits in the temperature register always read as 0 (not shown in the table below). Table 1. Temperature Data Format Note: Table 1 does not provide data formats for all temperatures.

Figure 1. Status of the ALERT Pin in Different Modes the Comparator Mode or Interrupt Mode to achieve different alarm functions. prevents false alerts as a result of environmental noise. TLOW for a consecutive number of fault conditions, and remains active until cleared by a read operation of any register. The cycle repeats with the ALERT pin becoming active when the temperature equals or exceeds THIGH, and so on. modes is illustrated in Figure 1.

generates the start and stop conditions. an acknowledge bit and pulling SDA low. addressed on a single bus. Table 2 describes the pin logic levels and the corresponding address values. Table 2. Address Pin Connections and Slave Addresses

1001000 GND GND GND

1001001 GND GND V+

1001010 GND V+ GND

1001011 GND V+ V+

1001100 V+ GND GND

1001101 V+ GND V+

1001110 V+ V+ GND

1001111 V+ V+ V+

a particular register on the TMP75 is accomplished by writing the appropriate value to the pointer register. The value for the pointer register is the first byte transferred after the slave address byte with the R/W bit low. Every write operation to the TMP75 requires a value for the pointer register (see Figure 2). When reading from the TMP75, the last value stored in the pointer register by a write operation is used to determine which register is read by a read operation. To change the register pointer for a read operation, a new value must be written to the pointer register. This action is accomplished by issuing a slave address byte with the R/W bit low, followed by the pointer register byte. No additional data are required. The master can then generate a start condition and send the slave address byte with the R/W bit high to initiate the read command. See Figure 3 for details of this sequence. If repeated reads from the same register are desired, there is no need to continually send the pointer register bytes because the TMP75 stores the pointer register value until it is changed by the next write operation. Note that register bytes are sent with the most significant byte first, followed by the least significant byte. High-Speed Mode In order for the I 2C bus to operate at frequencies above 400 kHz, the master device must issue an Hs-mode code (00001xxx) as the first byte after a start condition to switch the bus to high-speed operation. The TMP75 does not acknowledge this byte, but does switch its input filters on SDA and SCL and its output filters on SDA to operate in Hs-mode, allowing transfers at up to 2.75 MHz. After the Hs-mode code has been issued, the master transmits a slave address to initiate a data-transfer operation. The bus continues to operate in Hs-mode until a stop condition occurs on the bus. Upon receiving the stop condition, the TMP75 switches the input and output filters back to fast- mode operation. Time-Out Function The TMP75 resets the serial interface if SCL or SDA are held low for 22 ms (typ) between a start and stop condition. If the TMP75 is pulled low, it releases the bus and then waits for a start condition. To avoid activating the timeout function, it is necessary to maintain a communication speed of at least 1 kHz for the SCL operating frequency. UMW Rwww.umw-ic.com 8 UTD Semiconductor Co.,Limited TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R

Figure 4. Conversion Diagram conversions and stores each result to the Temperature register, overwriting the result from the previous conversion. then powers down and waits for a delay 54 ms. during delay is 2.2 μA (typical at +25°C). subsequent write to the one-shot register triggers another single conversion followed by a return to shutdown state. This mode reduces power consumption in the TMP75 when continuous temperature monitoring is not required. the OS bit, and a write to the one-shot register has no effect.

Table 5. Temperature Register (pointer=0h) (reset=0000h) Table 6. Temperature Register Description Table 7. THIGH Register (pointer=2h) (reset=5000h) [1] Table 8. TLOW Register (pointer=3h) (reset=4B00h) [2]

Table 9. Configuration Register (pointer=1h) (reset=0000h) Table 10. Configuration Register Description SD=0 & OS=1 : one-shot mode; writing any value to the one-shot register initiates a conversion. SD=1 & OS=x : shutdown mode; the status of the OS bit has no effect.

Application and Implementation The TMP75 only requires pull-up resistors on SDA and ALERT, although a pull-up resistor is typically present on the SCL as well. A 0.1-μF bypass capacitor on the supply is recommended, as shown in Figure 6. The SCL, SDA, and ALERT lines can be pulled up to a supply that is equal to or higher than V+ through the pull-up resistors. To configure one of eight different addresses on the bus, connect A0, A1, and A2 to either V+ or GND. The TMP75 should be placed in close proximity to the heat source to be monitored, with a proper layout for good thermal coupling. This ensures that temperature changes are captured within the shortest possible time interval. To maintain accuracy in applications that require air or surface temperature measurement, take care to isolate the package and leads from ambient air temperature. A thermally-conductive adhesive is helpful in achieving accurate surface temperature measurement.Figure 6. Typical Connections of the TMP75 I2C Master SDA SCL ALERT 5kΩ 0.1μF Supply Voltage 1.4V~5.5V 5GND A2 6TMP75 UMW Rwww.umw-ic.com 13 UTD Semiconductor Co.,Limited TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R

Rwww.umw-ic.com 14 UTD Semiconductor Co.,Limited TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R

Order code Package Baseqty Deliverymode SOP-8 4000 Tape and reel UMW TMP75AIDGKR MSOP-8 4000 Tape and reel UMW Rwww.umw-ic.com 15 UTD Semiconductor Co.,Limited TMP75 1.8V Digital Temperature Sensor with I2C Interface and Alarm Function UMW R