MCP9808 MICROCHIP [Microchip Technology], MCP9808 Datasheet
MCP9808
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MCP9808 Summary of contents
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... This sensor has an industry standard 400 kHz, 2-wire, 2 SMBus/I C compatible serial interface, allowing up to eight or sixteen sensors to be controlled with a single serial bus (see Table 3-2 for available Address codes). These features make the MCP9808 ideal for sophisticated, multi-zone, temperature-monitoring applications. Package Types 8-Pin 2x3 DFN* 8-Pin MSOP ...
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... MCP9808 Functional Block Diagram Register Pointer DS25095A-page 2 Hysteresis Shutdown Critical Trip Lock Alarm Window Lock Clear Alert Alert Status Output Control Critical Alert only Alert Polarity Alert Comp./Int. Configuration Temperature T Limit UPPER T Limit LOWER T Limit CRITICAL Manufacturer ID Device ID/Rev ...
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... Threshold for falling V — -0.1 — °C Section 5.2.3 “Alert Output Configuration” — — 1 µA V — — 0 — 0.7 — s Time to 63% (+89°C) — 1.4 — s MCP9808 Conditions = 3. 3. 2.7V to 5.5V +25° (Active-Low, Pull-up Resistor (Active-Low, Pull-up Resistor) OL DS25095A-page 3 ...
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... MCP9808 DIGITAL INPUT/OUTPUT PIN CHARACTERISTICS Electrical Specifications: Unless otherwise indicated -40°C to +125°C. A Parameters Serial Input/Output (SCL, SDA, A0, A1, A2) Input High-Level Voltage Low-Level Voltage Input Current Output (SDA) Low-Level Voltage High-Level Current (leakage) Low-Level Current SDA and SCL Inputs Hysteresis ...
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... I C interface will time-out. A Repeat Start command 2 C bus system, but the requirement avoid unintended generation of Start or Stop F MAX t HIGH HD-DI/ HD-DO SU-DI Data Transmission MCP9808 = -40°C to +125°C, GND = Ground Units Conditions (Note 2, 4) kHz (Note 2) ns (Note ...
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... MCP9808 NOTES: DS25095A-page 6 © 2011 Microchip Technology Inc. ...
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... Histogram. 40 85° 3.3V DD 859 units 30% 20% 10% 0% FIGURE 2-5: Histogram 100° 3.3V DD 856 units 30% 20% 10% 0% FIGURE 2-6: Histogram, T MCP9808 and DD Temperature Accuracy (°C) Temperature Accuracy Temperature Accuracy (°C) Temperature Accuracy = +85°C. A Temperature Accuracy (°C) Temperature Accuracy = +100°C. A DS25095A-page 7 ...
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... MCP9808 Note: Unless otherwise indicated -40°C to +125° -40° 3.3V DD 240 units 30% 20% 10% 0% Temperature Accuracy (°C) FIGURE 2-7: Temperature Accuracy Histogram -40°C. A 400 350 300 250 200 150 100 -40 - Temperature (°C) FIGURE 2-8: Supply Current vs. ...
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... OL Temperature. 2.00 1.50 1.00 0.50 0.00 100 120 -40 FIGURE 2-17: Temperature. 1.0 ∆°C/∆V 0.5 0.0 -0.5 No decoupling capacitor -1.0 100 100 FIGURE 2-18: Frequency. MCP9808 and 100 120 Temperature (°C) SMBus Time-out vs. - 100 120 Temperature (°C ) Shutdown Current 3.3V + 150 +25°C = 25°C ...
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... MCP9808 NOTES: DS25095A-page 10 © 2011 Microchip Technology Inc. ...
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... Section 4.0 “Serial Communication”.) (See 3.3 Temperature Alert, Open-Drain Output (Alert) The MCP9808 temperature Alert output pin is an open-drain output. The device outputs a signal when the ambient temperature goes beyond the user-programmed Section 5.2.3 “Alert Output temperature limit. (See Configuration”). 3.4 Ground Pin (GND) The GND pin is the system ground pin ...
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... MCP9808 NOTES: DS25095A-page 12 © 2011 Microchip Technology Inc. ...
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... MASTER/SLAVE The bus is controlled by a master device (typically a microcontroller) that controls the bus access and generates the Start and Stop conditions. The MCP9808 is a slave device and does not control other devices in the bus. Both master and slave devices can operate as either transmitter or receiver ...
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... MCP9808 4.1.4 ADDRESS BYTE Following the Start condition, the host must transmit an 8-bit address byte to the MCP9808. The address for the MCP9808 temperature sensor is ‘0011,A2,A1,A0’ in binary, where the A2, A1 and A0 bits are set externally by connecting the corresponding pins to V ‘0’. The 7-bit address, transmitted in the serial bit stream, must match the selected address for the MCP9808 to respond with an ACK ...
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... FUNCTIONAL DESCRIPTION The MCP9808 temperature sensors consist of a band- gap-type temperature sensor, a Delta-Sigma Analog-to- Digital Converter (ΔΣ ADC), user-programmable 2 registers and a 2-wire SMBus/I C protocol compatible serial interface. Figure 5-1 shows a block diagram of the register structure. Register Pointer FIGURE 5-1: Functional Block Diagram. ...
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... The Temperature CONV Alert Upper Boundary and Lower Boundary Limit registers are read/write registers. If the ambient temperature drifts beyond the user-specified limits, the MCP9808 outputs a signal using the Alert pin (refer to REGISTER 5-1: REGISTER POINTER (WRITE-ONLY) W-0 W-0 W-0 — ...
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... SIGN 2 °C A LOWER °C 2 °C 2 ° MCP9808 Hysteresis SHDN Alt Sel Alt Pol Alt Mod °C 2 °C 2 ° ° °C 2 ° ...
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... MCP9808 5.1.1 SENSOR CONFIGURATION REGISTER (CONFIG) The MCP9808 has a 16-bit Configuration register (CONFIG) that allows the user to set various functions for a robust temperature monitoring system. Bits 10 through 0 are used to select the temperature alert output hysteresis, device shutdown or Low-Power mode, temperature boundary and critical temperature lock, and temperature Alert output enable/disable ...
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... Microchip Technology Inc. Default”). Window Lock bit LOWER and T registers can be written (power-up default) LOWER registers can not be written LOWER Default”). , T and T (power-up default) LOWER CRIT and T temperature boundaries are disabled) UPPER LOWER MCP9808 (Section 5.3 (Section 5.3 DS25095A-page 19 ...
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... Section 4.1.4 “Address //WRITE Command (see //also, make sure bit 0 is cleared ‘0’ // Write CONFIG Register // Write data // Write data // send STOP command MCP9808 Byte”) Section 4.0 “Serial © 2011 Microchip Technology Inc. ...
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... Command //also, make sure bit 0 is set ‘1’ // READ 8 bits //and Send ACK bit // READ 8 bits //and Send NAK bit // send STOP command MCP9808 Note not necessary to select the Register Pointer if it was set from the previous read/write. ...
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... If this feature is enabled (Section 5.1.1 (CONFIG)”) and the ambient temperature exceeds the ), a 16-bit UPPER specified boundary or window, the MCP9808 asserts an Alert output. (Refer to Configuration”). /T UPPER/LOWER/CRITICAL TEMPERATURE LIMIT REGISTER CRIT R/W-0 ...
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... MCP9808 MSB Data Master MCP9808 MCP9808 LSB Data MCP9808 Note not necessary to select the Register Pointer if it was set from the previous read/write ...
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... MCP9808 5.1.3 AMBIENT TEMPERATURE REGISTER ( The MCP9808 uses a band gap temperature sensor circuit to output analog voltage proportional to absolute temperature. An internal ΔΣ ADC is used to convert the analog voltage to a digital word. The digital word is loaded to a 16-bit read-only Ambient Temperature (T ) register ...
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... A CRIT //T > UPPER //T < LOWER //Clear flag bits //T < 0°C A //Clear SIGN //T ³ 0°C A //Temperature = Ambient Temperature (°C) MCP9808 Example 5-1, shows the Figure 5-5 for the timing BYTES TO TEMPERATURE CONVERSION ≥ 0° – 4 × × LowerByte 2 4 – 4 × ...
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... MSB Data Master MCP9808 Note not necessary to select the Register Pointer if it was set from the previous read/write LSB Data ...
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... MANUFACTURER ID REGISTER This register is used to identify the manufacturer of the device in order to perform manufacturer-specific operation. The Manufacturer ID for the MCP9808 is 0x0054 (hexadecimal). REGISTER 5-5: MANUFACTURER ID REGISTER – READ-ONLY (→ ADDRESS ‘0000 0110’b) R-0 R-0 R-0 bit 15 R-0 R-1 R-0 bit 7 Legend Readable bit W = Writable bit -n = Value at POR ‘1’ = Bit is set ...
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... The upper byte of this register is used to specify the device identification and the lower byte is used to specify the device revision. The Device ID for the MCP9808 is 0x04 (hex). The revision begins with 0x00 (hex) for the first release, with the number being incremented as revised versions are released ...
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... Resolution Pointer MCP9808 MCP9808 Resolution to +0.0625°C <0000 0011>b (see A MCP9808 U-0 R/W-1 R/W-1 — Resolution bit Bit is unknown Data MCP9808 DS25095A-page 29 ...
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... Alert output to deassert. Comparator mode is useful for thermostat type applications, such as turning on a cooling fan or triggering a system shutdown when the temperature exceeds a safe operating range MCP9808 R PU Active-Low Alert Output and T registers. These bits LOWER CRIT ...
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... Acknowledge the interrupt by setting bit 5 of the CONFIG register from the MCP9808. © 2011 Microchip Technology Inc. 5.2.4 TEMPERATURE RESOLUTION The MCP9808 is capable of providing temperature the polarity data with +0.5°C to +0.0625°C resolution. The resolu- tion can be selected using the Resolution register UPPER (Register 5-7 located at address, ‘ ...
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... MCP9808 T CRIT T UPPER LOWER T Comparator Interrupt S/w Int. Clear Critical Only Comparator Interrupt S/w Int. Clear Critical Only Notes: 1 Alert Output Boundary Notes Conditions ≥ LOWER < – LOWER HYST > UPPER ≤ – UPPER HYST ≥ ...
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... Summary of Power-on Default The MCP9808 has an internal Power-on Reset (POR) circuit. If the power supply voltage the V threshold, the device resets the registers to POR the power-on default settings. Table 5-3 shows the power-on default summary for the Temperature Sensor registers. TABLE 5-3: POWER-ON RESET DEFAULTS ...
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... MCP9808 NOTES: DS25095A-page 34 © 2011 Microchip Technology Inc. ...
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... A potential for self-heating errors can exist if the MCP9808 SDA, SCL and Event lines are heavily loaded with pull-ups (high current). Typically, the self-heating error is negligible because of the relatively small current consumption of the MCP9808. A temper- FIGURE 6-1: DFN Package Layout (Top View). © 2011 Microchip Technology Inc. ...
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... MCP9808 NOTES: DS25095A-page 36 © 2011 Microchip Technology Inc. ...
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... Note: In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. © 2011 Microchip Technology Inc. MCP9808 Example ALP 141 25 Example ...
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... MCP9808 /HDG 3ODVWLF 'XDO )ODW 1R /HDG 3DFNDJH 0& ± [[ PP %RG\ >')1@ 1RWH NOTE TOP VIEW A3 1RWHV DS25095A-page EXPOSED PAD BOTTOM VIEW A NOTE NOTE © 2011 Microchip Technology Inc. ...
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... Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging © 2011 Microchip Technology Inc. MCP9808 DS25095A-page 39 ...
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... MCP9808 /HDG 3ODVWLF 0LFUR 6PDOO 2XWOLQH 3DFNDJH 06 >0623@ 1RWH NOTE 1RWHV DS25095A-page φ L © 2011 Microchip Technology Inc. ...
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... Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging © 2011 Microchip Technology Inc. MCP9808 DS25095A-page 41 ...
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... MCP9808 NOTES: DS25095A-page 42 © 2011 Microchip Technology Inc. ...
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... Microchip Technology Inc. Software License Agreement // Digital Output (make it input only when reading data) // Digital Output // enable I2C Master mode // clear control bits // disable slew rate control; disable SMBus // set baud rate to 100 kHz (Fosc = 48 MHz) // force idle condition MCP9808 DS25095A-page 45 ...
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... MCP9808 /******************************************************************** * Function Name: i2c_start * Return Value: void * Parameters: void * Description: Send I2C Start Command ********************************************************************/ void i2c_start(void) { PIR1bits.SSPIF = 0; //clear flag while (SSPSTATbits.BF ); SSPCON2bits.SEN = 1; while (!PIR1bits.SSPIF) ; PIR1bits.SSPIF = 0; // clear flag } /******************************************************************** * Function Name: i2c_repStart * Return Value: void * Parameters: void * Description: Resend I2C Start Command * ********************************************************************/ void i2c_repStart(void) { PIR1bits.SSPIF = 0 ...
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... Load SSPBUF with i2cWriteData (the value to be transmit- // wait for a flag to be set // enable receive mode // Read SSPBUF and put it in i2cReadData // if ack=1 // then transmit an Acknowledge // otherwise transmit a Not Acknowledge // send acknowledge sequence // return the value read from SSPBUF MCP9808 DS25095A-page 47 ...
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... MCP9808 NOTES: DS25095A-page 48 © 2011 Microchip Technology Inc. ...
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... APPENDIX B: REVISION HISTORY Revision A (October 2011) • Original Release of this Document. © 2011 Microchip Technology Inc. MCP9808 DS25095A-page 49 ...
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... MCP9808 NOTES: DS25095A-page 50 © 2011 Microchip Technology Inc. ...
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... Temperature and/or Range Alternate Pinout Device: MCP9808: Digital Temperature Sensor MCP9808T: Digital Temperature Sensor (Tape and Reel) Temperature Range -40°C to +125°C Package Plastic Dual Flat No-Lead (DFN) 2x3, 8-lead MS = Plastic Micro Small Outline (MSOP), 8-lead © 2011 Microchip Technology Inc. ...
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... MCP9808 NOTES: DS25095A-page 52 © 2011 Microchip Technology Inc. ...
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Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families ...
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