MCP9800A0T-M/OTG

MCP9800/1/2/3 2-Wire High-Accuracy Temperature Sensor Features: Description: • Temperature-to-Digital Converter • Accuracy with 12-bit Resolution: - ±0.5°C (typical) at +25°C - ±1°C (maximum) from -10°C to +85°C - ±2°C (maximum) from -10°C to +125°C - ±3°C (maximum) from -55°C to +125°C • User-selectable Resolution: 9-12 bit • Operating Voltage Range: 2.7V to 5.5V • 2-wire Interface: I2C™/SMBus Compatible • Operating Current: 200 µA (typical) • Shutdown Current: 1 µA (maximum) • Power-saving One-shot Temperature Measurement • Available Packages: SOT-23-5, MSOP-8, SOIC-8 Microchip Technology Inc.’s MCP9800/1/2/3 family of digital temperature sensors converts temperatures between -55°C and +125°C to a digital word. They provide an accuracy of ±1°C (maximum) from -10°C to +85°C. Typical Applications: • • • • • • • Personal Computers and Servers Hard Disk Drives and Other PC Peripherals Entertainment Systems Office Equipment Data Communication Equipment Mobile Phones General Purpose Temperature Monitoring VDD PIC® Microcontroller GND 2 ALERT 3 5 4 R SDA SCLK RPULL-UP PIC16F737 I2C™ Port VDD 1 This sensor has an industry standard 2-wire, I2C™/ SMBus compatible serial interface, allowing up to eight devices to be controlled in a single serial bus. These features make the MCP9800/1/2/3 ideal for sophisticated multi-zone temperature-monitoring applications. Package Types Typical Application MCP9800/02 The MCP9800/1/2/3 family comes with user-programmable registers that provide flexibility for temperature sensing applications. The register settings allow user-selectable 9-bit to 12-bit temperature measurement resolution, configuration of the power-saving Shutdown and One-shot (single conversion on command while in Shutdown) modes and the specification of both temperature alert output and hysteresis limits. When the temperature changes beyond the specified limits, the MCP9800/1/2/3 outputs an alert signal. The user has the option of setting the alert output signal polarity as an active-low or active-high comparator output for thermostat operation, or as temperature event interrupt output for microprocessor-based systems. MCP9800 MCP9802 MCP9801 MCP9803 SOT-23-5 VDD 1 SOIC, MSOP 5 SDA GND 2 ALERT 3 I/O Port 4 SCLK SDA 1 8 VDD SCLK 2 7 A0 ALERT 3 GND 4 6 A1 5 A2 MCP9802/03: Serial Bus time-out 35 ms (typ.) MCP9800/01: No Serial Bus time-out  2010 Microchip Technology Inc. DS21909D-page 1 MCP9800/1/2/3 NOTES: DS21909D-page 2  2010 Microchip Technology Inc. MCP9800/1/2/3 1.0 ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings † VDD....................................................................... 6.0V †Notice: Stresses above those listed under “Maximum ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. Voltage at all Input/Output pins .....GND – 0.3V to 5.5V Storage temperature .......................... -65°C to +150°C Ambient temp. with power applied ..... -55°C to +125°C Junction Temperature (TJ) ................................. 150°C ESD protection on all pins (HBM:MM) .......(4 kV:400V) Latch-Up Current at each pin ........................ ±200 mA DC CHARACTERISTICS Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground, and TA = -55°C to +125°C. Parameters Sym Min Typ Max Unit Conditions Operating Voltage Range VDD 2.7 — 5.5 V Operating Current IDD — 200 400 µA Continuous Operation Shutdown Current ISHDN — 0.1 1 µA Shutdown mode Power-on-Reset Threshold (POR) VPOR — 1.7 — V VDD falling edge Δ°C/ΔV — 0.2 — °C/V TACY — ±0.5 — °C VDD = 3.3V -10°C < TA  +85°C TACY -1.0 — +1.0 °C VDD = 3.3V -10°C < TA  +125°C TACY -2.0 — +2.0 °C VDD = 3.3V -55°C < TA  +125°C TACY -3.0 — +3.0 °C VDD = 3.3V 9-bit Resolution tCONV — 30 75 ms 33 samples/sec (typical) 10-bit Resolution tCONV — 60 150 ms 17 samples/sec (typical) 11-bit Resolution tCONV — 120 300 ms 8 samples/sec (typical) 12-bit Resolution tCONV — 240 600 ms 4 samples/sec (typical) High-level Current IOH — — 1 µA VOH = 5V Low-level Voltage VOL — — 0.4 V IOL= 3 mA tRES — 1.4 — s Time to 63% (89°C) 27°C (Air) to 125°C (oil bath) Power Supply Line Regulation VDD = 2.7V to 5.5V Temperature Sensor Accuracy Accuracy with 12-bit Resolution: TA = +25°C Internal  ADC Conversion Time: Alert Output (Open-drain) Thermal Response Response Time  2010 Microchip Technology Inc. DS21909D-page 3 MCP9800/1/2/3 DIGITAL INPUT/OUTPUT PIN CHARACTERISTICS Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground and TA = -55°C to +125°C. Parameters Sym Min Typ Max Units Conditions Serial Input/Output (SCLK, SDA, A0, A1, A2) Input High-level Voltage VIH 0.7 VDD — — V Low-level Voltage VIL — — 0.3 VDD V Input Current IIN -1 — +1 µA Low-level Voltage VOL — — 0.4 V IOL= 3 mA High-level Current IOH — — 1 µA VOH = 5V Low-level Current IOL 6 — — mA VOL = 0.6V CIN — 10 — pF VHYST 0.05 VDD — — V Output (SDA) Capacitance SDA and SCLK Inputs Hysteresis Graphical Symbol Description INPUT OUTPUT Voltage Voltage VDD VDD VIH VOL VIL Time Time Current Current IOL IIN IOH Time Time TEMPERATURE CHARACTERISTICS Electrical Specifications: Unless otherwise indicated, VDD = +2.7V to +5.5V, GND = Ground. Parameters Sym Min Typ Max Units Conditions Temperature Ranges Specified Temperature Range TA -55 — +125 °C Operating Temperature Range TA -55 — +125 °C Storage Temperature Range TA -65 — +150 °C (Note 1) Thermal Package Resistances Thermal Resistance, 5L-SOT23 JA — 256 — °C/W Thermal Resistance, 8L-SOIC JA — 163 — °C/W Thermal Resistance, 8L-MSOP JA — 206 — °C/W Note 1: Operation in this range must not cause TJ to exceed Maximum Junction Temperature (+150°C). DS21909D-page 4  2010 Microchip Technology Inc. MCP9800/1/2/3 SERIAL INTERFACE TIMING SPECIFICATIONS Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground, -55°C < TA < +125°C, CL = 80 pF, and all limits measured to 50% point. Parameters Min Typ Max Units fSC 0 — 400 kHz I2C MCP9800/01 fSC 10 — 400 kHz SMBus MCP9802/03 tSC 2.5 — — µs tLOW 1.3 — — µs High Clock tHIGH 0.6 — — µs Rise Time tR 20 — 300 ns 10% to 90% of VDD (SCLK, SDA) Fall Time tF 20 — 300 ns 90% to 10% of VDD (SCLK, SDA) tSU-DATA 0.1 — — µs Data Hold After SCLK Low tH-DATA 0 — 0.9 µs Start Condition Setup Time tSU-START 0.6 — — µs Start Condition Hold Time tH-START 0.6 — — µs Stop Condition Setup Time tSU-STOP 0.6 — — µs Bus Idle tIDLE 1.3 — — µs Time Out tOUT 25 35 50 ms 2-Wire Sym Conditions I2 C™/SMBus Compatible Interface Serial Port Frequency Clock Period Low Clock Data Setup Before SCLK High MCP9802/03 only EE TO -F R U -S tB tS W O tL tH tH Start Condition  2010 Microchip Technology Inc. AT A -D tH tS U -D AT A tR ,t F SD A SC L tS U IG H P -S TA R T -S TA R T Timing Diagram Data Transmission Stop Condition DS21909D-page 5 MCP9800/1/2/3 NOTES: DS21909D-page 6  2010 Microchip Technology Inc. MCP9800/1/2/3 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore, outside the warranted range. Note: Unless otherwise noted: VDD = 2.7V to 5.5V. 85 105 125 Temperature Accuracy (°C) FIGURE 2-1: Average Temperature Accuracy vs. Ambient Temperature, VDD = 3.3V. 2.0 1.0 400 12-Bit Resolution 160 Samples VDD = 2.7V VDD = 3.3V VDD = 5.0V VDD = 5.5V 350 -1.0 50 5 25 45 TA (°C) 65 85 Resolution -55 -35 -15 105 125 FIGURE 2-2: Average Temperature Accuracy vs. Ambient Temperature. FIGURE 2-5: Temperature. 5 25 45 TA (°C) 65 85 105 125 Supply Current vs. Ambient 1 VDD = 3.3V 160 Samples 2.0 0.8 ISHDN (µA) 11-Bit 12-Bit 0.0 -1.0 -2.0 200 100 -3.0 1.0 VDD = 5.0V VDD = 5.5V 250 150 -2.0 3.0 VDD = 2.7V VDD = 3.3V 300 0.0 -55 -35 -15 Temperature Accuracy (°C) FIGURE 2-4: Temperature Accuracy Histogram, TA = +25°C. IDD (µA) Temperature Accuracy (°C) 3.0 3.0 65 2.5 25 45 TA (°C) 2.0 5 1.5 -15 1.0 -35 0.5 -55 -3.0 Spec. Limits -3.0 0.0 -2.0 -0.5 -1.0 -1.0 0.0 5 lots 32 Samples/lot 160 Samples -1.5 1.0 TA = +25°C VDD = 3.3V -2.0 2.0 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% -2.5 VDD= 3.3V 12-Bit Resolution 160 Samples Occurrences Temperature Accuracy (°C) 3.0 9-Bit 10-Bit 0.6 0.4 0.2 -3.0 0 -55 -35 -15 5 25 45 TA (°C) 65 85 105 125 FIGURE 2-3: Average Temperature Accuracy vs. Ambient Temperature, VDD = 3.3V.  2010 Microchip Technology Inc. -55 -35 -15 5 25 45 TA (°C ) 65 85 105 125 FIGURE 2-6: Shutdown Current vs. Ambient Temperature. DS21909D-page 7 MCP9800/1/2/3 Note: Unless otherwise noted: VDD = 2.7V to 5.5V. 145 VOL = 0.6V 42 VDD = 5.5V VDD = 3.3V VDD = 2.7V 36 30 24 18 12 105 85 65 SOIC 45 MSOP SOT-23 25 27°C (Air) to 125°C (Oil bath) 6 -55 -35 -15 5 25 45 TA (°C) 65 85 105 125 0.4 5 -2 0 2 4 6 8 10 12 14 16 18 20 Time (s) FIGURE 2-7: ALERT and SDA IOL vs. Ambient Temperature. ALERT & SDA V OL (V) Average of 10 samples per package 125 Temperature Data (°C) ALERT & SDA I OL (mA) 48 FIGURE 2-9: MCP980X Thermal Response vs Time. IOL = 3mA 0.3 VDD = 5.5V VDD = 3.3V VDD = 2.7V 0.2 0.1 0 -55 -35 -15 5 25 45 TA (°C) 65 85 105 125 FIGURE 2-8: ALERT and SDA Output VOL vs. Ambient Temperature. DS21909D-page 8  2010 Microchip Technology Inc. MCP9800/1/2/3 3.0 PIN DESCRIPTION The descriptions of the pins are listed in Table 3-1. TABLE 3-1: 3.1 PIN FUNCTION TABLE MCP9800 MCP9802 SOT-23-5 MCP9801 MCP9803 MSOP, SOIC Symbol 5 1 SDA 4 2 SCLK Serial Clock Input 3 3 ALERT Temperature Alert Output 2 4 GND 5 A2 Address Select Pin (bit 2) — 6 A1 Address Select Pin (bit 1) — 7 A0 Address Select Pin (bit 0) 1 8 VDD Power Supply Input Serial Data Pin (SDA) Serial Clock Pin (SCLK) The SCLK is a clock input pin. All communication and timing is relative to the signal on this pin. The clock is generated by the host controller on the bus. 3.3 Power Supply Input (VDD) The VDD pin is the power pin. The operating voltage, as specified in the DC electrical specification table, is applied on this pin. 3.4 Bidirectional Serial Data — The SDA is a bidirectional input/output pin, used to serially transmit data to and from the host controller. This pin requires a pull-up resistor to output data. 3.2 Function Ground (GND) The GND pin is the system ground pin. Ground 3.5 ALERT Output The MCP9800/1/2/3’s ALERT pin is an open-drain output pin. The device outputs an alert signal when the ambient temperature goes beyond the user-programmed temperature limit. 3.6 Address Pins (A2, A1, A0) These pins are device or slave address input pins and are available only with the MCP9801/03. The device addresses for the MCP9800/02 are factory-set. The address pins are the Least Significant bits (LSb) of the device address bits. The Most Significant bits (MSb) (A6, A5, A4, A3) are factory-set to . This is illustrated in Table 3-2. TABLE 3-2: Device A6 A5 A4 A3 A2 A1 A0 MCP9800/02A0 1 0 0 1 0 0 0 MCP9800/02A1 1 0 0 1 0 0 1 MCP9800/02A2 1 0 0 1 0 1 0 MCP9800/02A3 1 0 0 1 0 1 1 MCP9800/02A4 1 0 0 1 1 0 0 MCP9800/02A5 1 0 0 1 1 0 1 MCP9800/02A6 1 0 0 1 1 1 0 MCP9800/02A7 1 0 0 1 1 1 1 MCP9801/03 1 0 0 1 X X X Note:  2010 Microchip Technology Inc. SLAVE ADDRESS User-selectable address is shown by X. DS21909D-page 9 MCP9800/1/2/3 NOTES: DS21909D-page 10  2010 Microchip Technology Inc. MCP9800/1/2/3 4.0 SERIAL COMMUNICATION 4.1.1 4.1 2-Wire SMBus/Standard Mode I2C™ Protocol-Compatible Interface Data transfers are initiated by a Start condition (Start), followed by a 7-bit device address and a read/write bit. An Acknowledge (ACK) from the slave confirms the reception of each byte. Each access must be terminated by a Stop condition (Stop). The MCP9800/1/2/3 serial clock input (SCL) and the bidirectional serial data line (SDA) form a 2-wire bidirectional SMBus/Standard mode I2C compatible communication port (refer to the Digital Input/Output Pin Characteristics Table and Serial Interface Timing Specifications Table). The following bus protocol has been defined: TABLE 4-1: Term MCP9800 SERIAL BUS PROTOCOL DESCRIPTIONS Description Master The device that controls the serial bus, typically a microcontroller. Slave The device addressed by the master, such as the MCP9800/1/2/3. Transmitter Device sending data to the bus. Receiver Device receiving data from the bus. Start A unique signal from master to initiate serial interface with a slave. Stop A unique signal from the master to terminate serial interface from a slave. Read/Write A read or write to the MCP9800/1/2/3 registers. ACK A receiver Acknowledges (ACK) the reception of each byte by polling the bus. NAK A receiver Not-Acknowledges (NAK) or releases the bus to show End-of-Data (EOD). Busy Communication is not possible because the bus is in use. Not Busy The bus is in the Idle state, both SDA and SCL remain high. Data Valid SDA must remain stable before SCL becomes high in order for a data bit to be considered valid. During normal data transfers, SDA only changes state while SCL is low.  2010 Microchip Technology Inc. DATA TRANSFER Repeated communication is initiated after tB-FREE. This device does not support sequential register read/ write. Each register needs to be addressed using the Register Pointer. This device supports the Receive Protocol. The register can be specified using the pointer for the initial read. Each repeated read or receive begins with a Start condition and address byte. The MCP9800/1/2/3 retains the previously selected register. Therefore, it outputs data from the previously-specified register (repeated pointer specification is not necessary). 4.1.2 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 MCP9800/1/2/3 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. However, the master device determines which mode is activated. 4.1.3 START/STOP CONDITION A high-to-low transition of the SDA line (while SCL is high) is the Start condition. All data transfers must be preceded by a Start condition from the master. If a Start condition is generated during data transfer, the MCP9800/1/2/3 resets and accepts the new Start condition. A low-to-high transition of the SDA line (while SCL is high) signifies a Stop condition. If a Stop condition is introduced during data transmission, the MCP9800/1/ 2/3 releases the bus. All data transfers are ended by a Stop condition from the master. 4.1.4 ADDRESS BYTE Following the Start condition, the host must transmit an 8-bit address byte to the MCP9800/1/2/3. The address for the MCP9800 Temperature Sensor is ‘1001,A2,A1,A0’ in binary, where the A2, A1 and A0 bits are set externally by connecting the corresponding pins to VDD ‘1’ or GND ‘0’. The 7-bit address transmitted in the serial bit stream must match the selected address for the MCP9800/1/2/3 to respond with an ACK. Bit 8 in the address byte is a read/write bit. Setting this bit to ‘1’ commands a read operation, while ‘0’ commands a write operation (see Figure 4-1). DS21909D-page 11 MCP9800/1/2/3 4.1.6 Address Byte 1 SCL 2 1 SDA 0 3 4 5 6 7 8 A C K 1 A2 A1 A0 0 9 Start Address Code Slave Address R/W PIC18FXXXX Response FIGURE 4-1: 4.1.5 Device Addressing. DATA VALID After the Start condition, each bit of data in transmission needs to be settled for a time specified by tSU-DATA before SCL toggles from low-to-high (see “Serial Interface Timing Specifications” on Page 5). DS21909D-page 12 ACKNOWLEDGE (ACK) Each receiving device, when addressed, is obliged to generate an ACK bit after the reception of each byte. The master device must generate an extra clock pulse for ACK to be recognized. The acknowledging device pulls down the SDA line for tSU-DATA before the low-to-high transition of SCL from the master. SDA also needs to remain pulled down for tH-DATA after a high-to-low transition of SCL. During read, the master must signal an End-of-Data (EOD) to the slave by not generating an ACK bit (NAK) once the last bit has been clocked out of the slave. In this case, the slave will leave the data line released to enable the master to generate the Stop condition.  2010 Microchip Technology Inc. MCP9800/1/2/3 5.0 FUNCTIONAL DESCRIPTION The MCP9800/1/2/3 temperature sensor consists of a band-gap type temperature sensor, a  Analog-toDigital Converter (ADC), user-programmable registers and a 2-wire I2C protocol-compatible serial interface. Resolution 5.1 Temperature Sensor The MCP9800/1/2/3 uses the difference in the baseemitter voltage of a transistor while its collector current is changed from IC1 to IC2. With this method, the VBE depends only on the ratio of the two currents and the ambient temperature, as shown in Equation 5-1. EQUATION 5-1: One-Shot Shutdown Fault Queue Alert Polarity kT 0.5°C 0.25°C 0.125°C 0.0625°C  V BE =  ------  ln  IC 1  IC 2  q Where: T = temperature in kelvin VBE = change in diode base-emitter voltage Alert Comp/Int k = Boltzmann's constant Configuration Register Temperature Register THYST Register Band-Gap Temperature Sensor TSET Register Register Pointer FIGURE 5-1: q = electron charge  ADC I2C™ Interface Functional Block Diagram.  2010 Microchip Technology Inc. IC1 and IC2 = currents with n:1 ratio 5.2  Analog-to-Digital Converter A Sigma-Delta ADC is used to convert VBE to a digital word that corresponds to the transistor temperature. The converter has an adjustable resolution from 0.5°C (at 30 ms conversion time) to 0.0625°C (at 240 ms conversion time). Thus, it allows the user to make trade-offs between resolution and conversion time. Refer to Section 5.3.2 “Sensor Configuration Register (CONFIG)” and Section 5.3.4.7 “ ADC Resolution” for details. DS21909D-page 13 MCP9800/1/2/3 5.3 Registers Resolution The MCP9800/1/2/3 has four registers that are user-accessible. These registers are specified as the Ambient Temperature (TA) register, the Temperature Limit-set (TSET) register, the Temperature Hysteresis (THYST) register and device Configuration (CONFIG) register. One-Shot Shutdown Fault Queue The Ambient Temperature register is a read-only register and is used to access the ambient temperature data. The data from the ADC is loaded in parallel in the register. The Temperature Limit-set and Temperature Hysteresis registers are read/write registers that provide user-programmable temperature limits. If the ambient temperature drifts beyond the programmed limits, the MCP9800/1/2/3 outputs an alert signal using the ALERT pin (refer to Section 5.3.4.3 “ALERT Output Configuration”). The device Configuration register provides access for the user to configure the MCP9800/1/2/3’s various features. These registers are described in further detail in the following sections. Alert Polarity Alert Comp/Int Configuration Register THYST Register ALERT Output Control Logic TSET Register The registers are accessed by sending Register Pointers to the MCP9800/1/2/3 using the serial interface. This is an 8-bit pointer. However, the two Least Significant bits (LSbs) are used as pointers and all other bits need to be cleared . This device has additional registers that are reserved for test and calibration. If these registers are accessed, the device may not perform according to the specification. The pointer description is shown below. REGISTER 5-1: ALERT Output Temperature Register FIGURE 5-2: Register Block Diagram. REGISTER POINTER U-0 U-0 U-0 U-0 U-0 U-0 R/W-0 R/W-0 0 0 0 0 0 0 P1 P0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-2 Unimplemented: Read as ‘0’ bit 1-0 Px: Pointer bits 00 = Temperature register (TA) 01 = Configuration register (CONFIG) 10 = Temperature Hysteresis register (THYST) 11 = Temperature Limit-set register (TSET) x = Bit is unknown . DS21909D-page 14  2010 Microchip Technology Inc. MCP9800/1/2/3 TABLE 5-1: Register Pointer P1 P0 MSB/ LSB BIT ASSIGNMENT SUMMARY FOR ALL REGISTERS Bit Assignment 7 Ambient Temperature Register (TA) 0 0 6 5 4 3 2 1 0 23°C 22°C 21°C 20°C 0 0 0 0 ALERT Polarity COMP/INT Shutdown MSB Sign 26°C 25°C 24°C LSB 2-1°C 2-2°C 2-3°C 2-4°C Sensor Configuration Register (CONFIG) 0 1 LSB One-Shot Resolution Fault Queue Temperature Hysteresis Register (THYST) 1 0 MSB Sign 26°C 25°C 24°C 23°C 22°C 21°C 20°C LSB 2-1°C 0 0 0 0 0 0 0 Temperature Limit-Set Register (TSET) 1 1 MSB Sign 26°C 25°C 24°C 23°C 22°C 21°C 20°C LSB 2-1°C 0 0 0 0 0 0 0  2010 Microchip Technology Inc. DS21909D-page 15 MCP9800/1/2/3 5.3.1 AMBIENT TEMPERATURE REGISTER (TA) EQUATION 5-2: The MCP9800/1/2/3 has a 16-bit read-only Ambient Temperature register that contains 9-bit to 12-bit temperature data. (0.5°C to 0.0625°C resolutions, respectively). This data is formatted in two’s complement. The bit assignments, as well as the corresponding resolution, is shown in the register assignment below. T A = Code  2 –4 Where: TA = Ambient Temperature (°C) Code = MCP9800 output in decimal The refresh rate of this register depends on the selected ADC resolution. It takes 30 ms (typical) for 9-bit data and 240 ms (typical) for 12-bit data. Since this register is double-buffered, the user can read the register while the MCP9800/1/2/3 performs Analog-to-Digital conversion in the background. The decimal code to ambient temperature conversion is shown in Equation 5-2: REGISTER 5-2: AMBIENT TEMPERATURE REGISTER (TA) – ADDRESS b Upper Half: R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0 Sign 26 °C 25 °C 24 °C 23 °C 22 °C 21 °C 20 °C bit 15 bit 8 Lower Half: R-0 2 -1 °C/bit R-0 R-0 R-0 R-0 R-0 R-0 R-0 2-2 °C 2-3 °C 2-4 °C 0 0 0 0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared Note 1: x = Bit is unknown When the 0.5°C, 0.25°C or 0.125°C resolutions are selected, bit 6, bit 7 or bit 8 will remain clear , respectively. DS21909D-page 16  2010 Microchip Technology Inc. MCP9800/1/2/3 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 Note: SCL SDA S 1 0 0 A 2 1 A 1 A A 0 W C K 0 0 0 Address Byte 0 0 0 0 It is not necessary to select the Register Pointer if it was set from the previous read/ write. (see Section 4.1.1) A C K 0 TA Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 R C 1 2 3 4 5 6 7 8 0 0 0 1 1 0 0 1 1 2 3 4 5 6 7 8 0 1 0 0 0 0 0 0 SCL SDA S A K Address Byte A C K P LSB Data MSB Data PIC18FXXX N A K Master Master FIGURE 5-3: Timing Diagram for Reading +25.25°C Temperature from the TA Register (See Section 5.3.1 “Ambient Temperature Register (TA)”).  2010 Microchip Technology Inc. DS21909D-page 17 MCP9800/1/2/3 5.3.2 SENSOR CONFIGURATION REGISTER (CONFIG) The MCP9800/1/2/3 has an 8-bit read/write Configuration register that allows the user to select the different features. These features include shutdown, ALERT output select as comparator or interrupt output, ALERT output polarity, fault queue cycle, temperature measurement resolution and One-shot mode (single conversion while in shutdown). These functions are described in detail in the following sections. REGISTER 5-3: R/W-0 CONFIGURATION REGISTER (CONFIG) – ADDRESS b R/W-0 One-Shot R/W-0 R/W-0 Resolution R/W-0 Fault Queue R/W-0 R/W-0 R/W-0 ALERT Polarity COMP/INT Shutdown bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 ONE-SHOT bit 1 = Enabled 0 = Disabled (Power-up default) bit 5-6  ADC RESOLUTION bits 00 = 9 bit or 0.5°C (Power-up default) 01 = 10 bit or 0.25°C 10 = 11 bit or 0.125°C 11 = 12 bit or 0.0625°C bit 3-4 FAULT QUEUE bits 00 = 1 (Power-up default) 01 = 2 10 = 4 11 = 6 bit 2 ALERT POLARITY bit 1 = Active-high 0 = Active-low (Power-up default) bit 1 COMP/INT bit 1 = Interrupt mode 0 = Comparator mode (Power-up default) bit 0 SHUTDOWN bit 1 = Enable 0 = Disable (Power-up default) DS21909D-page 18 x = Bit is unknown  2010 Microchip Technology Inc. MCP9800/1/2/3 • Writing to the CONFIG Register to change the resolution to 0.0625°C b. 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 W C 1 2 3 4 5 6 7 8 0 0 0 0 0 0 0 1 SCL SDA S A K Address Byte A C K CONFIG Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 0 1 1 0 0 0 0 0 1 A C K P MSB Data PIC18FXXX • Reading the CONFIG Register. 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 Note: SCL SDA S 1 0 0 A 2 1 A 1 A A 0 W C K 0 0 Address Byte 0 0 0 0 0 A C K 1 It is not necessary to select the Register Pointer if it was set from the previous read/ write (see Section 4.1.1). CONFIG Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 R C 1 2 3 4 5 6 7 8 0 1 1 0 0 0 0 0 SCL SDA S A K Address Byte N A K P Data PIC18FXXX FIGURE 5-4: Timing Diagram for Writing and Reading from the Configuration Register (See Section 5.3.2 “Sensor Configuration Register (CONFIG)”).  2010 Microchip Technology Inc. DS21909D-page 19 MCP9800/1/2/3 5.3.3 TEMPERATURE HYSTERESIS REGISTER (THYST) The MCP9800/1/2/3 has a 16-bit read/write Temperature Hysteresis register that contains a 9-bit data in two’s compliment format. This register is used to set a hysteresis for the TSET limit. Therefore, the data represents a minimum temperature limit. If the ambient temperature drifts below the specified limit, the MCP9800/1/2/3 asserts an alert output (refer to Section 5.3.4.3 “ALERT Output Configuration”). This register uses the nine Most Significant bits (MSbs) and all other bits are “don’t cares”. The power-up default value of THYST register is 75°C, or b in binary. REGISTER 5-4: TEMPERATURE HYSTERESIS REGISTER (THYST) – ADDRESS b Upper Half: R/W-0 Sign R/W-1 R/W-0 R/W-0 R/W-1 R/W-0 R/W-1 R/W-1 6 °C 25 °C 24 °C 23 °C 22 °C 21 °C 20 °C 2 bit 15 bit 8 Lower Half: R/W-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0 2-1 °C 0 0 0 0 0 0 0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared DS21909D-page 20 x = Bit is unknown  2010 Microchip Technology Inc. MCP9800/1/2/3 • Writing to the THYST Register to set the temperature hysteresis to 95°C b. 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 W C 1 2 3 4 5 6 7 8 0 0 0 0 0 0 1 0 SCL SDA S A K Address Byte A C K THYST Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 0 1 0 1 1 1 1 1 A C K 1 2 3 4 5 6 7 8 0 0 0 0 0 0 0 0 MSB Data A C K P LSB Data PIC18FXX PIC18FXXX • Reading the THYST Register. 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 Note: SCL SDA S 1 0 0 A 2 1 A 1 A A 0 W C K 0 0 Address Byte 0 0 0 0 1 It is not necessary to select the Register Pointer if it was set from the previous read/ write (see Section 4.1.1). A C K 0 THYST Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 R C 1 2 3 4 5 6 7 8 0 1 0 1 1 1 1 1 1 2 3 4 5 6 7 8 0 0 0 0 0 0 0 0 SCL SDA S A K Address Byte A C K P LSB Data MSB Data PIC18FXXX N A K Master Master FIGURE 5-5: Timing Diagram for Writing and Reading from the Temperature Hysteresis Register (See Section 5.3.3 “Temperature Hysteresis Register (THYST)”).  2010 Microchip Technology Inc. DS21909D-page 21 MCP9800/1/2/3 5.3.4 TEMPERATURE LIMIT-SET REGISTER (TSET) The MCP9800/1/2/3 has a 16-bit read/write Temperature Limit-Set register (TSET) which contains a 9-bit data in two’s compliment format. This data represents a maximum temperature limit. If the ambient temperature exceeds this specified limit, the MCP9800/1/2/3 asserts an alert output. (Refer to Section 5.3.4.3 “ALERT Output Configuration”). This register uses the nine Most Significant bits (MSbs) and all other bits are “don’t cares”. The power-up default value of the TSET register is 80°C, or b in binary. REGISTER 5-5: TEMPERATURE LIMIT-SET REGISTER (TSET) – ADDRESS b Upper Half: R/W-0 R/W-1 R/W-0 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 Sign 26 °C 25 °C 24 °C 23 °C 22 °C 21 °C 20 °C bit 15 bit 8 Lower Half: R/W-0 2 -1 °C R-0 R-0 R-0 R-0 R-0 R-0 R-0 0 0 0 0 0 0 0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared DS21909D-page 22 x = Bit is unknown  2010 Microchip Technology Inc. MCP9800/1/2/3 • Writing to the TSET Register to set the temperature limit to 90°C, b 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 W C 1 2 3 4 5 6 7 8 0 0 0 0 0 0 1 1 SCL SDA S A K Address Byte A C K TSET Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 0 1 0 1 1 0 1 0 A C K 1 2 3 4 5 6 7 8 0 0 0 0 0 0 0 0 MSB Data A C K P LSB Data PIC18FXX PIC18FXXX • Reading the TSET Register. 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 Note: SCL SDA S 1 0 0 A 2 1 A 1 A A 0 W C K 0 0 0 Address Byte 0 0 0 1 It is not necessary to select the Register Pointer if it was set from the previous read/ write. (see Section 4.1.1) A C K 1 TSET Pointer PIC18FXXX PIC18FXXX 1 2 3 4 5 6 7 8 1 0 0 1 A 2 A 1 A 0 R C 1 2 3 4 5 6 7 8 0 1 0 1 1 0 1 0 1 2 3 4 5 6 7 8 0 0 0 0 0 0 0 0 SCL SDA S A K Address Byte A C K P LSB Data MSB Data PIC18FXXX N A K Master Master FIGURE 5-6: Timing Diagram for Writing and Reading from the Temperature Limit-set Register (See Section 5.3.4 “Temperature Limit-Set Register (TSET)”).  2010 Microchip Technology Inc. DS21909D-page 23 MCP9800/1/2/3 5.3.4.1 5.3.4.3 Shutdown Mode The Shutdown mode disables all power-consuming activities (including temperature sampling operations) while leaving the serial interface active. The device consumes 2 µA (maximum) in this mode. It remains in this mode until the Configuration register is updated to enable continuous conversion or until power is recycled. In Shutdown mode, the CONFIG, TA, TSET and THYST registers can be read or written to; however, the serial bus activity will increase the shutdown current. 5.3.4.2 One-Shot Mode The MCP9800/1/2/3 can also be used in a One-shot mode that can be selected using bit 7 of the CONFIG register. The One-shot mode performs a single temperature measurement and returns to Shutdown mode. This mode is especially useful for low-power applications where temperature is measured upon command from a controller. For example, a 9-bit TA in One-shot mode consumes 200 µA (typical) for 30 ms and 0.1 µA (typical) during shutdown. To access this feature, the device needs to initially be in Shutdown mode. This is done by sending a byte to the CONFIG register with bit 0 set and bit 7 cleared . Once the device is in Shutdown mode, the CONFIG register needs to be written to again, with bit 0 and bit 7 set . This begins the single conversion cycle of tCONV, 30ms for 9-bit data. Once the conversion is completed, TA is updated and bit 7 of CONFIG becomes cleared by the MCP9800/1/2/3. TABLE 5-2: SHUTDOWN AND ONE-SHOT MODE DESCRIPTION Operational Mode One-Shot (Bit 7) Shutdown (Bit 0) Continuous Conversion 0 0 Shutdown 0 1 Continuous Conversion 1 0 (One-shot is ignored) One-shot (Note 1) 1 1 Note 1: The shutdown command needs to be programmed before sending a one-shot command . ALERT Output Configuration The ALERT output can be configured as either a comparator output or as Interrupt Output mode using bit 1 of CONFIG. The polarity can also be specified as an active-high or active-low using bit 2 of CONFIG. The following sections describe each output mode, while Figure 5-7 gives a graphical description. 5.3.4.4 Comparator Mode In Comparator mode, the ALERT output is asserted when TA is greater than TSET. The pin remains active until TA is lower than THYST. The 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. In Comparator mode, if the device enters the Shutdown mode with asserted ALERT output, the output remains active during shutdown. The device must be operating in continuous conversion, with TA below THYST, for the ALERT output to be deasserted. 5.3.4.5 Interrupt Mode In Interrupt mode, the ALERT output is asserted when TA is greater than TSET. However, the output is deasserted when the user performs a read from any register. This mode is designed for interrupt-driven, microcontroller-based systems. The microcontroller receiving the interrupt will have to acknowledge the interrupt by reading any register from the MCP9800/1/ 2/3. This will clear the interrupt and the ALERT pin will become deasserted. When TA drifts below THYST, the MCP9800/1/2/3 outputs another interrupt and the controller needs to read a register to deassert the ALERT output. Shutting down the device will also reset, or deassert, the ALERT output. TSET TA THYST ALERT Comparator mode Active-low ALERT Interrupt mode Active-low Register Read * * See Section 5.3.4.5 “Interrupt Mode” FIGURE 5-7: DS21909D-page 24 Alert Output.  2010 Microchip Technology Inc. MCP9800/1/2/3 5.3.4.6 5.4 Fault Queue The fault queue feature can be used as a filter to lessen the probability of spurious activation of the ALERT pin. TA must remain above TSET for the consecutive number of conversion cycles selected using the Fault Queue bits. Bit 3 and bit 4 of CONFIG can be used to select up to six fault queue cycles. For example, if six fault queues are selected, TA must be greater than TSET for six consecutive conversions before ALERT is asserted as a comparator or an interrupt output. This queue setting also applies for THYST. If six fault queues are selected, TA must remain below THYST for six consecutive conversions before ALERT is deasserted (Comparator mode) or before another interrupt is asserted (Interrupt mode). 5.3.4.7 The MCP9800/1/2/3 has an internal Power-on Reset (POR) circuit. If the power supply voltage VDD glitches down to the 1.7V (typical) threshold, the device resets the registers to the power-up default settings. Table 5-4 shows the power-up default summary. TABLE 5-4: POWER-UP DEFAULTS Register Data (Hex) TA TSET THYST Pointer 0000 A000 9600 00 CONFIG 00  ADC Resolution The MCP9800/1/2/3 provides access to select the ADC resolution from 9-bit to 12-bit (0.5°C to 0.0625°C resolution) using bit 6 and bit 5 of the CONFIG register. The user can gain better insight into the trends and characteristics of the ambient temperature by using a finer resolution. Increasing the resolution also reduces the quantization error. Figure 2-3 shows accuracy versus resolution. Table 5-3 shows the TA register conversion time for the corresponding resolution. TABLE 5-3: Summary of Power-up Condition Power-up Defaults 0°C 80°C 75°C Temperature register Continuous Conversion Comparator mode Active-low Output Fault Queue 1 9-bit Resolution At power-up, the MCP9800/1/2/3 has an inherent 2 ms (typical) power-up delay before updating the registers with default values and start a conversion cycle. This delay reduces register corruption due to unsettled power. After power-up, it takes tCONV for the TCN75A to update the TA register with valid temperature data. RESOLUTION AND CONVERSION TIME Bits Resolution tCONV (typical) 9 10 11 12 0.5 0.25 0.125 0.0625 30 ms 60 ms 120 ms 240 ms  2010 Microchip Technology Inc. DS21909D-page 25 MCP9800/1/2/3 NOTES: DS21909D-page 26  2010 Microchip Technology Inc. MCP9800/1/2/3 6.0 APPLICATIONS INFORMATION 6.1 Connecting to the Serial Bus The SDA and SCL serial interface are open-drain pins that require pull-up resistors. This configuration is shown in Figure 6-1. VDD R R SDA SCL PIC® MCU FIGURE 6-1: Interface. MCP9800/1/2/3 Pull-up Resistors on Serial The MCP9800/1/2/3 is designed to meet 0.4V (maximum) voltage drop at 3 mA of current. This allows the MCP9800/1/2/3 to drive lower values of pull-up resistors and higher bus capacitance. In this application, all devices on the bus must meet the same pull-down current requirements. 6.2 The ALERT output can be wired with a number of other open-drain devices. In such applications, the output needs to be programmed as an active-low output. Most systems will require pull-up resistors for this configuration. 6.3 The MCP9800/1/2/3 does not require any additional components besides the master controller in order to measure temperature. However, it is recommended that a decoupling capacitor of 0.1 µF to 1 µF be used between the VDD and GND pins. A high-frequency ceramic capacitor is recommended. It is necessary for the capacitor to be located as close as possible to the power pins in order to provide effective noise protection. For applications where a switching regulator is used to power the sensor, it is recommended to add a 200Ω resistor in series to VDD to filter out the switcher noise from the sensor. It is also recommended to add the series resistor in applications where a linear regulator is used to step-down a switching regulator voltage to power the sensor. For example, if a linearly regulated 3.3V from a 5V switching regulator is used to power the sensor, add a 200Ω series resistor (refer to Figure 6-3). MCP9800/1/2/3 Typical Application Microchip provides several microcontroller product lines with Master Synchronous Serial Port modules (MSSP) that include the I2C interface mode. This module implements all master and slave functions and simplifies the firmware development overhead. Figure 6-2 shows a typical application using the PIC16F737 as a master to control other Microchip slave products, such as EEPROM, fan speed controllers and the MCP9800 temperature sensor connected to the bus. PIC16F737 Microcontroller 24LC01 EEPROM TC654 Fan Speed Controller TCN75A Temperature Sensor FIGURE 6-2: Bus. Multiple Devices on I2C™  2010 Microchip Technology Inc. 200 Switching Regulator VDD 0.1 µF bypass MCP9800/1/2/3 Switching Regulator Linear Regulator FIGURE 6-3: Single Resistor. 6.4 SDA SCL Layout Considerations 200 VDD 0.1 µF bypass Power-supply Filter Using a Thermal Considerations The MCP9800/1/2/3 measures temperature by monitoring the voltage of a diode located in the die. A low-impedance thermal path between the die and the Printed Circuit Board (PCB) is provided by the pins. Therefore, the MCP9800/1/2/3 effectively monitors the temperature of the PCB. However, the thermal path for the ambient air is not as efficient because the plastic device package functions as a thermal insulator. A potential for self-heating errors can exist if the MCP9800/1/2/3 SDA and SCL communication lines are heavily loaded with pull-ups. Typically, the self-heating error is negligible because of the relatively small current consumption of the MCP9800/1/2/3. However, in order to maximize the temperature accuracy, the SDA and SCL pins need to be lightly loaded. DS21909D-page 27 MCP9800/1/2/3 NOTES: DS21909D-page 28  2010 Microchip Technology Inc. MCP9800/1/2/3 7.0 PACKAGING INFORMATION 7.1 Package Marking Information 5-Lead SOT-23 Example: XXNN Part Number LDNN MCP9802A0T-M/OT JKNN LENN MCP9802A1T-M/OT JLNN MCP9800A2T-M/OT LFNN MCP9802A2T-M/OT JMNN MCP9800A3T-M/OT LGNN MCP9802A3T-M/OT JPNN MCP9800A4T-M/OT LHNN MCP9802A4T-M/OT JQNN MCP9800A5T-M/OT LJNN MCP9802A5T-M/OT JRNN MCP9800A6T-M/OT LKNN MCP9802A6T-M/OT JSNN MCP9800A7T-M/OT LLNN MCP9802A7T-M/OT JTNN Example: 9803M 044256 8-Lead SOIC (150 mil) e3 * Note: MCP9802 MCP9800A1T-M/OT XXXXX YWWNNN Legend: XX...X Y YY WW NNN Part Number MCP9800A0T-M/OT 8-Lead MSOP XXXXXXXX XXXXYYWW NNN MCP9800 Example: MCP9803 SN1044 256 Customer-specific information Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn) This package is Pb-free. The Pb-free JEDEC designator ( e3 ) can be found on the outer packaging for this package. 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.  2010 Microchip Technology Inc. DS21909D-page 29 MCP9800/1/2/3        .#  #$ # / !- 0    #  1/ %## !# ## +22--- 2 / b N E E1 3 2 1 e e1 D A2 A c φ A1 L L1 3#   4# 5$8 %1 44"" 5 56 7 5 ( 4 !1# ()* 6$# ! 4 !1#  6, 9 #   : ! !1/ /  ; :  #!%%   : ( 6,  : > 4 !/  ; : = 4 !