Datasheet MCP9808 Datasheet

MCP9808

±0.5°C Maximum Accuracy Digital Temperature Sensor

Features

•Accuracy:

- ±0.25 (typical) from -40°C to +125°C

- ±0.5°C (maximum) from -20°C to 100°C

- ±1°C (maximum) from -40°C to +125°C

• User-Selectable Measurement Resolution:

- +0.5°C, +0.25°C, +0.125°C, +0.0625°C

• User-Programmable Temperature Limits:

- Temperature Window Limit

- Critical Temperature Limit

• User-Programmable Temperature Alert Output

• Operating Voltage Range: 2.7V to 5.5V

• Operating Current: 200 µA (typical)

• Shutdown Current: 0.1 µA (typical)

• 2-wire Interface: I

C™/SMBus Compatible

• Available Packages: 2x3 DFN-8, MSOP-8

Typical Applications

• General Purpose

• Industrial Applic atio ns

• Industrial Freezers and Refrigerators

• Food Processing

• Personal Computers and Servers

• PC Peripherals

• Consumer Electronics

• Handheld/Portable Devices

Temperature Accuracy

40%

TA= -20°C, 25°C, 85°C, 100°C

= 3.3V

854 units

30%

Description

Microchip Technology Inc.’s MCP9808 digital temperature sensor converts temperatures between

-20°C and +100°C to a digital word with ±0.25°C/±0.5°C (typical/maximum) accuracy.

The MCP9808 comes with user-programmable registers that provide flexibility for temperature sensing applications. The registers allow user-selectable settings such as Shutdown or Low-Power modes and the specification of temperature Alert window limits and critical output limits. When the temperature changes beyond the specified boundary limits, the MCP9808 outputs an Alert signal. The user has the option of setting the Alert output signal polarity as an active-low or activehigh comparator output for thermostat operation, or as a temperature Alert interrupt output for microprocessorbased systems. The Alert output can also be configured as a critical temperature output only.

This sensor has an industry standard 400 kHz, 2-wire, SMBus/I

C compatible se rial interfa ce, 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*

SDA V

SCL

Alert

GND

* Includes Exposed Thermal Pad (EP); see Table 3-1 .

8-Pin MSOP

SDA

SCL

Alert

GND

A1 A2

20%

Occurrences

10%

0.0

0.1

0.2

0.3

0.4

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.5

MCP9808

Functional Block Diagram

Hysteresis Shutdown Critical Trip Lock

Alarm Window Lock

Clear Alert Alert Status

Output Co ntrol Critical Alert only Alert Polarity Alert Comp./Int.

Configuration

Band Gap

Temperature

Sensor

Pointer

Temperature T

T T

Manufacturer ID

Device ID/Rev Resolution

UPPER LOWER CRITICAL

Alert

Limit

SMBus/Standard I2C™

Interface

SDA

SCL

ΔΣ ADC

+0.5°C

+0.25°C

+0.125°C

+0.0625°C

GND

MCP9808

1.0 ELECTRICAL CHARACTERISTICS

†Notice: S tress es ab ove th ose li ste d under “Maxim um

ratings” may ca use permanen t damage to the de vice. This is a stress rating only and functional operation of the device at tho se or any oth er conditions ab ove those

Absolute Maximum Ratings †

VDD.................................................................................. 6.0V

Voltage at All Input/Output Pins .............. GND – 0.3V to 6.0V

Storage Temperature ....................................-65°C to +150°C

Ambient Temperature with Power Applied....-40°C to +125°C

Junction Temperature (T

ESD Protection on All Pins (HBM:MM) ................ (4 kV:400V)

Latch-up Cu rr e n t at Ea c h Pi n (+ 2 5 °C ) ................ ..... ±200 mA

) ..........................................+150°C

indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.

TEMPERATURE SENSOR DC CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground and

= -40°C to +125°C.

Parameters Sym Min Typ Max Unit Conditions

Temperature Sensor Accuracy

-20°C < T

-40°C < TA ≤ +125°C -1.0 ±0.25 +1.0 °C VDD = 3.3V

Temperature Conversion Time

0.5°C/bit t

0.25°C/bit — 65 — ms 15s/sec (typical)

0.125°C/bit — 130 — ms 7s/sec (typical)

0.0625°C/bit — 250 — ms 4s/sec (typical)

Power Supply

Operating Voltage Range V Operating Current I Shutdown Current I Power-on Reset (POR) V Power Supply Rejection Δ°C/ΔV

Alert Output (open-drain output, external pull-up resistor required), see Section 5.2.3 “Alert Output Configuration”

High-Level Current (leakage) I Low-Level Voltage V

Thermal Response, from +25°C (air) to +125°C (oil bath)

8L-DFN t 8L-MSOP — 1.4 — s

≤ +100°C T

ACY

CONV

SHDN

POR

RES

-0.5 ±0.25 +0.5 °C VDD = 3.3V

— 30 — ms 33s/sec (typical)

2.7 — 5.5 V —200 400 µA —0.1 2 µA — 2.2 — V Threshold for falling V —-0.1 — °C/VVDD = 2.7V to 5.5V, TA = +25°C

—— 1 µAV

= VDD (Active-Low, Pull-up Resistor)

—— 0.4 VIOL= 3 mA (Active-Low, Pull-up Resistor)

— 0.7 — s Time to 63% (+89°C)

MCP9808

DIGITAL INPUT/OUTPUT PIN CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground and

= -40°C to +125°C.

Parameters Sym Min Typ Max Units Conditions

Serial Input/Output (SCL, SDA, A0, A1, A2)

Input

High-Level Voltage V Low-Level Voltage V Input Current I

Output (SDA)

Low-Level Voltage V High-Level Current (leakage) I Low-Level Current I

OL OH OL

SDA and SCL Inputs

Hysteresis V Spike Suppression t Capacitance C

HYST

GRAPHICAL SYMBOL DESCRIPTION

0.7 V

GND — 0.3 V

—VDDV

——±5µA

——0.4VI ——1µAV

6——mAV

—0.05 VDD—V ——50ns —5—pF

= 3 mA

OH OL

= 5.5V

= 0.6V

Volta ge

Current

INPUT

Vol tage

Current

time

TEMPERATURE CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V and GND = Ground.

Parameters Sym Min Typ Max Units Conditions

Temperature Ranges

Specified Temperature Range T Operating Temperature Range T Storage Temperature Range T

A A A

Thermal Package Resistances

Thermal Resistance, 8L-DFN θ Thermal Resistance, 8L-MSOP θ

JA JA

Note 1: Operation in this range must not cause T

-40 — +125 °C (Note 1)

-40 — +125 °C

-65 — +150 °C

—68—°C/W —211—°C/W

to exceed Maximum Junction Temperature (+150°C).

OUTPUT

MCP9808

SENSOR SERIAL INTERFACE TIMING SPECIFICATIONS

Electrical Specifications: Unless otherwise indicated, VDD = 2.7V to 5.5V, TA = -40°C to +125°C, GND = Ground

= 80 pF. (Note 1)

and C

Parameters Sym Min Max Units Conditions

2-Wire SMBus/Standard Mode I

Serial Port Clock Frequency f Low Clock t High Clock t Rise Time t Fall Time t Data in Setup Time t Data In Hold Time t Data Out Hol d Time t Start Condition Setup Time t Start Condition Hold Time t Stop Condition Setup Time t Bus Free t Time-out t Bus Capacitive Load C

Note 1: All values referred to V

2: If t

LOW

> t

OUT

or t

is required for communication.

3: This device can be used in a Standard mode I

be met. This device does not stretch the SCL Low time.

4: As a transmitter, the device provides internal minimum delay time, t

region (min. 200 ns) of the falling edge of SCL, t conditions.

5: As a receiver, SDA should not be sampled at the falling edge of SCL. SDA can transition t

SCL toggles Low.

C™ Compatible Interface (Note 1)

LOW

HIGH

F SU-DI HD-DI

HD-DO SU-START HD-START

SU-STOP

B-FREE

OUT

HIGH

and V

IL MAX

> t

, the temperature senso r I2C interface will time-out. A Repeat Start comm and

OUT

IH MIN

levels.

0400kHz(Note 2, 4)

1300 — ns (Note 2)

600 — ns (Note 2)

20 300 ns 20 300 ns

100 — ns (Note 3)

0—ns(Note 5) 200 900 ns (Note 4) 600 — ns 600 — ns 600 — ns

1300 — ns

25 35 ms —400pf

C bus system, but the requirement, t

, to avoid unintended generation of Start or Stop

F MAX

HD-DO MIN

SU-DI

, to bridge the undefined

≥ 100 ns, must

0 ns after

HD-DI

TIMING DIAGRAM

HD-START

SU-START

HIGH

LOW

SCL

SDA

OUT

SU-DI

START Condition

HD-DI/tHD-DO

Data Transmission

tR, t

B-FREE

SU-STOP

STOP Condition

MCP9808

NOTES:

MCP9808

2.0 TYPICAL PERFORMANCE CURVES

Note: The graphs and t ables provid ed follo wing this no te are a st atis tical summa ry bas ed on a lim ited nu mber 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 indicated, VDD = 2.7V to 5.5V, GND = Ground, SDA/SCL pulled-up to VDD and T

= -40°C to +125°C.

1.0

0.5

= 3.3V

854 units at -20°C, 25°C, 85°C, 100°C 240 units at -40°C, 125°C

0.0

Temperature Accuracy (°C)

-0.5

-1.0

+Std. Dev.

Average

-Std. Dev.

+3 * Std. Dev.

-3 * Std. Dev.

-40 -20 0 20 40 60 80 100 120

TA(°C)

FIGURE 2-1: Temperature Accuracy.

40%

TA= -20°C

= 3.3V

827 units

30%

20%

Occurrences

10%

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.0

0.1

0.2

0.3

FIGURE 2-2: Temperature Accuracy Histogram, T

40%

30%

= -20°C.

TA= 25°C

= 3.3V

875 units

0.4

0.5

40%

TA= -20°C, 25°C, 85°C, 100°C

= 3.3V

854 units

30%

20%

Occurrences

10%

0.0

0.1

0.2

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.3

FIGURE 2-4: Temperature Accuracy Histogram.

40%

TA= 85°C

= 3.3V

859 units

30%

20%

Occurrences

10%

0.0

0.1

0.2

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.3

FIGURE 2-5: Temperature Accuracy Histogram, T

40%

30%

= +85°C.

TA= 100°C V

= 3.3V

856 units

0.4

0.5

20%

Occurrences

10%

0.0

0.1

0.2

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.3

FIGURE 2-3: Temperature Accuracy Histogram, T

= +25°C.

0.4

0.5

20%

Occurrences

10%

0.0

0.1

0.2

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.3

FIGURE 2-6: Temperature Accuracy Histogram, T

= +100°C.

0.4

0.5

MCP9808

Note: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground, SDA/SCL pulled-up to VDD and

= -40°C to +125°C.

40%

TA= -40°C

= 3.3V

240 units

30%

40%

TA= 125°C

= 3.3V

240 units

30%

20%

Occurrences

10%

0.0

0.1

0.2

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.3

FIGURE 2-7: Temperature Accuracy Histogram, T

400

350

300

250

(µA)

200

150

100

= -40°C.

-40-20 0 20406080100120

Temperature (°C)

FIGURE 2-8: Supply Current vs. Temperature.

0.4

0.5

20%

Occurrences

10%

0.0

0.1

0.2

0.3

-0.5

-0.4

-0.3

-0.2

Temperature Accuracy (°C)

-0.1

0.4

FIGURE 2-10: Temperature Accuracy Histogram, T

1.00

0.50

0.00

-0.50

Temperature Accuracy (°C)

-1.00

= +125°C.

VDD= 2.7V

= 3.3V

= 5.5V

-40 -20 0 20 40 60 80 100 120

Temperature (°C)

∆°C/∆VDD = 0.1°C/V

FIGURE 2-11: Temperature Accuracy vs Supply Voltage.

0.5

2.5

(V)

POR

1.5

-40 -20 0 20 40 60 80 100 120

Temperature (°C)

FIGURE 2-9: Power-on Reset Threshold Voltage vs. Temperature.

1000

0.0625°C

(ms)

CONV

0.125°C

100

0.25°C

0.5°C

-40-20 0 20406080100120

Temperature (°C)

FIGURE 2-12: Temperature Conversion Time vs. Temperature.

MCP9808

Note: Unless otherwise indicated, VDD = 2.7V to 5.5V, GND = Ground, SDA/SCL pulled-up to VDD and

= -40°C to +125°C.

0.4

IOL = 3 mA

(V)

0.3

0.2

0.1

SDA V

Alert V

SDA & Alert Output V

-40 -20 0 20 40 60 80 100 120

Temperature (°C)

FIGURE 2-13: SDA and Alert Output VOL vs. Temperature.

VOL = 0.6V

(mA)

SDA I

-40 -20 0 20 40 60 80 100 120

Temperature (°C)

(ms)

OUT

C Bus t

SMBus/I

-40 -20 0 20 40 60 80 100 120

Temperature (°C)

FIGURE 2-16: SMBus Time-out vs. Temperature.

2.00

1.50

(µA)

1.00

SHDN

0.50

0.00

-40 -20 0 20 40 60 80 100 120

Temperature (°C )

FIGURE 2-14: SDA IOL vs. Temperature.

120%

100%

80%

60%

40%

20%

Thermal Response (%)

-2 0 2 4 6 8 10 12 14 16

MSOP-8 DFN-8

Room to +125°C (Oil bath)

Time (s)

FIGURE 2-15: Package Thermal Response.

FIGURE 2-17: Shutdown Current vs Temperature.

1.0

∆°C/∆VDD, VDD = 3.3V + 150 mV

0.5

0.0

-0.5

No decoupling capacit or

Normalized Temp. Error (°C)

-1.0

100 1,000 10,000 100,000 1,000,000

100 1k 10k 100k 1M

1k 10k 100k 1M100k 1M10k 100k 1M1k 10k 100k 1M

Frequency (Hz)

PP (AC)

TA = 25°C

TA = +25°C

FIGURE 2-18: Power Supply Rejection vs. Frequency.

MCP9808

NOTES:

3.0 PIN DESCRIPTION

The descriptions of the pins are listed in Table 3-1.

TABLE 3-1: PIN FUNCTION TABLE

DFN MSOP Symbol Pin Function

1 1 SDA Serial Data Line 2 2 SCL Serial Clock Line 3 3 Alert Temperature Alert Output 44 GNDGround 5 5 A2 Slave Address 6 6 A1 Slave Address 7 7 A0 Slave Address 88 V 9 — EP Exposed Thermal Pad (EP); must be connected to GND

Power Pin

MCP9808

3.1 Serial Data Line (SDA)

SDA is a bidirectional input/output pin, used to serially transmit data to/from the host controller. This pin requires a pull-up resistor. (See Section 4.0 “Serial

Communication”.)

3.2 Serial Clock Line (SCL)

The SCL is a clock input pin. All communication and timing is relative to the signal on this pin. The clock is generated by the host or master controller on the bus. (See Section 4.0 “Serial Communication”.)

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 temperature limit. (See Section 5.2.3 “Alert Output

Configuration”).

3.4 Ground Pin (GND)

The GND pin is the system ground pin.

3.5 Address Pins (A0, A1, A2)

These pins are device address input pins. The address pins correspond to the Least Significant

bits (LSbs) of th e ad dre ss bi t s a nd the Mo st Significant bits (MSbs): A6, A5, A4, A3. This is illustrated in

Table 3-2.

TABLE 3-2: MCP9808 ADDRESS BYTE

Device Address Code Slave

Address

A6 A5 A4 A3 A2 A1 A0

(1)

MCP9808 0011x MCP9808

Note 1: User-selectable address is shown by ‘x’.

(2)

1001xxx

A2, A1 and A0 must match the corresponding device pin configuration.

2: Contact factory for this address code.

3.6 Power Pin (VDD)

VDD is the power pin. The operating voltage range, as specified in the DC electrical specification table, is applied on this pin.

3.7 Exposed Thermal Pad (EP)

There is an internal electrical connection between the Exposed Thermal Pad (EP) and the GND pin. The EP may be connected to the syst em gro und on the Pri nted Circuit Board (PCB).

MCP9808

NOTES:

MCP9808

4.0 SERIAL COMMUNICATION

4.1 2-Wire Standard Mode I2C™ Protocol Compatible Interface

The MCP9808 Serial Clock (SCL) input and the bidirectional Serial Data (SDA) line form a 2-wire bidirectional, Standard mode, I communicati on po rt (re fer t o the Digital Input/Output

Pin Characteristics and Sensor Serial Interface Timing Specifications tables).

The following bus protocol has been defined:

TABLE 4-1: MCP9808 SERIAL BUS

PROTOCOL DESCRIPTIONS

Term Description

Master The device that controls the serial bus,

typically a microcontroller.

Slave The device addressed by the master,

such as the MCP9808. Transmitter Device sending data to the bus. Receiver Device receiving data from the bus. START A unique signal from the 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 MCP9808

registers. ACK A receiver Acknowledges (ACK) the

reception of eac h byte by pol ling the bu s. NAK A receive r 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 cha nges st a te

while SCL is low.

C compatible

4.1.1 DATA TRANSFER

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 receptio n of eac h byte . Each a ccess mus t be terminated by a Stop condition (STOP).

Repeated communication is initiated after t 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 spec ified using the pointer for the initi al read. Each repeated read or receive begins with a Start condition and address byte. The MCP9808 retains the previously selected register. Therefore, it outputs data from the previously spec ified re giste r (repeate d point er specification is not necessary).

B-FREE

4.1.2 MASTER/SLAVE

The bus is controlled by a master device (typically a microcontroller) that controls the bus access and generates the S tart and Stop co nditions. The M CP9808 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 trans ition of t he SDA line (while S CL is high) is the Start condition. All data transfers must be preceded by a Start condition from the master. A low-to-high transition of the SDA line (while SCL is high) signifies a Stop condition.

If a Start or Stop condition is introduced during data transmission, the MCP9808 releases the bus. All data transfers are ended by a Stop condition from the master.

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

‘1’ or GND

‘0’. The 7-bit address, transmitted in the serial bit stream, must match the selected address for the MCP9808 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).

Address Byte

SCL

SDA

See Table 3-2.

123456789

011A2A1A0

Start

Address

Code

Slave

Address

R/W

MCP9808 Response

A C K

FIGURE 4-1: Device Addressing.

4.1.5 DATA VALID

After the Start condition, each bit of data in the transmission needs to be s ettled for a tim e specified b y t

SU-DATA

before SCL t ogg les from low -to- hig h (s ee t he

Sensor Serial Interface T iming Specifications sect ion).

4.1.6 ACKNOWLEDGE (ACK/NAK)

Each receiving device, when addressed, must 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 d ev ice pulls down the SDA l in e f or t

SU-DATA

before the low-to-high transition of SCL from the master. SDA also needs to remain pulled down for t

after a high-to-low transition of SCL.

H-DATA

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.

4.1.7 TIME-OUT

If the SCL stays low or high for the time specified by t

, the MCP9808 temperature sensor resets the

OUT

serial interface. T his di ct ates th e min imum clock spee d as outlined in the specification.

5.0 FUNCTIONAL DESCRIPTION

The MCP9808 temperature sensors consist of a bandgap-type temperature sensor , a Delt a-Sigma Analog-toDigital Converter (ΔΣ ADC), user-programmable

registers and a 2-wire SMBus/I

serial interface. Figure 5-1 shows a block diagram of the register structure.

C protocol compatible

Hysteresis Shutdown Critical Trip Lock Alarm Win. Lock Clear Alert Alert Status

Output Co ntrol Critical Alert Only Alert Polarity Alert Comp/Int

Configuration

MCP9808

Band Gap

Temperature

Sensor

Pointer

Temperature

T T T

Manufactu r er I D

Device ID/Rev Resolution

UPPER LOWER CRITICAL

Alert

Limit Limit

Limit

SMBus/Standard I2C™

Interface

SDA

SCL

ΔΣ

ADC

+0.5°C

+0.25°C

+0.125°C

+0.0625°C

GND

FIGURE 5-1: Functional Block Diagram.

MCP9808

5.1 Registers

The MCP9808 has several registers that are user-accessible. These registers include the Temperature register, Configuration register, Temperature Alert Upper Boundary and Lower Boundary Limit registers, Critical Temperature Limit register, Manufacturer Identification reg ister and Device Ide ntification register .

The Te mperature register is read-only, used to access the ambient temperature data. This register is doublebuffered and it is updated every t 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

W-0 W-0 W-0 W-0 W-0 W-0 W-0 W-0

— — — — Pointer bits

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 x = Bit is unknown

. The T em perature

CONV

Section 5.2.3 “Alert Output Configuration”). In

addition, the Critical Temperature Limit register is used to provide an additional critical temperature limit.

The Configuration register provides access to configure the MCP9808 device’s various features. These registers are described in further detail in the following sections.

The registers are accessed by sending a Register Pointer to the MCP9808, using the serial interface. This is an 8-bit write-only po inter. However, the four Least Significant bit s are used as pointers and all u nused bit s (Register Pointer<7:4>) need to be cleared or set to ‘0’.

each register.

bit 7-4 W: Writable bits

Write ‘0’. Bits 7-4 must alway s be cleare d or wr itten to ‘ 0’. T his d evice ha s add itiona l regi ste rs tha t are re se rved

for test and calibration. If these registers are accessed, the device may not perform according to the specification.

bit 3-0 Pointer bits

0000 = RFU, Reserved for Future Use (Read-Only register) 0001 = Configuration register (CONFIG) 0010 = Alert Temperature Upper Boundary Trip register (T 0011 = Alert Temperature Lower Boundary Trip register (T 0100 = Critical Temperature Trip register (T 0101 = Temperature register (T 0110 = M anufacturer ID register 0111 = Device ID/Revision register 1000 = Resolution register 1xxx = Reserved

Note 1: Some registers contain calibration codes and should not be accessed.

(1)

)

CRIT

)

UPPER LOWER

)

+ 36 hidden pages

Datasheet MCP9808 Datasheet

Specifications and Main Features

Frequently Asked Questions

User Manual

1.0 ELECTRICAL CHARACTERISTICS

2.0 TYPICAL PERFORMANCE CURVES

FIGURE 2-1: Temperature Accuracy.

FIGURE 2-4: Temperature Accuracy Histogram.

FIGURE 2-8: Supply Current vs. Temperature.

FIGURE 2-11: Temperature Accuracy vs Supply Voltage.

FIGURE 2-9: Power-on Reset Threshold Voltage vs. Temperature.

FIGURE 2-12: Temperature Conversion Time vs. Temperature.

FIGURE 2-13: SDA and Alert Output VOL vs. Temperature.

FIGURE 2-16: SMBus Time-out vs. Temperature.

FIGURE 2-14: SDA IOL vs. Temperature.

FIGURE 2-15: Package Thermal Response.

FIGURE 2-17: Shutdown Current vs Temperature.

FIGURE 2-18: Power Supply Rejection vs. Frequency.

3.0 PIN DESCRIPTION

TABLE 3-1: PIN FUNCTION TABLE

3.1 Serial Data Line (SDA)

3.2 Serial Clock Line (SCL)

3.3 Temperature Alert, Open-Drain Output (Alert)

3.4 Ground Pin (GND)

3.5 Address Pins (A0, A1, A2)

TABLE 3-2: MCP9808 ADDRESS BYTE

3.6 Power Pin (VDD)

3.7 Exposed Thermal Pad (EP)

4.0 SERIAL COMMUNICATION

4.1 2-Wire Standard Mode I2C™ Protocol Compatible Interface

FIGURE 4-1: Device Addressing.

5.0 FUNCTIONAL DESCRIPTION

FIGURE 5-1: Functional Block Diagram.

5.1 Registers