MCP98243-BE/MC Microchip Technology, MCP98243-BE/MC Datasheet - Page 13

• Manufacturer Part Number: MCP98243-BE/MC
• Description: IC TEMP SENSOR 3V 2WIRE 8-DFN
• Manufacturer: Microchip Technology

Specifications of MCP98243-BE/MC

• Package / Case: 8-DFN
• Output Type: I²C™/SMBus™
• Function: Temp Monitoring System (Sensor)
• Topology: ADC (Sigma Delta), Register Bank
• Sensor Type: Internal
• Sensing Temperature: -40°C ~ 125°C
• Output Alarm: No
• Output Fan: Yes
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Full Temp Accuracy: +/- 3 C
• Digital Output - Bus Interface: Serial (2-Wire, I2C)
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Ic Output Type: Digital
• Sensing Accuracy Range: ± 0.5°C
• Temperature Sensing Range: -40°C To +125°C
• Supply Current: 200µA
• Supply Voltage Range: 2.7V To 5.5V
• Sensor Case Style: DFN
• No. Of Pins: 8
• Rohs Compliant: Yes
• Resolution (bits): 8bit
• Supply Voltage Min: 3V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

4.0
4.1
The MCP9843/98243 serial clock input (SCL) and the
bidirectional serial data line (SDA) form a 2-wire
bidirectional
communication port (refer to the Input/Output Pin DC
Characteristics (Note 1) Table and Sensor And
EEPROM Serial Interface Timing Specifications
Table).
The following bus protocol has been defined:
TABLE 4-1:
4.1.1
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).
Repeated communication is initiated after t
© 2009 Microchip Technology Inc.
Master
Slave
Transmitter Device sending data to the bus.
Receiver
START
STOP
Read/Write A read or write to the MCP9843/98243
ACK
NAK
Busy
Not Busy
Data Valid
Term
SERIAL COMMUNICATION
2-Wire Standard Mode I
Protocol-Compatible Interface
DATA TRANSFER
The device that controls the serial bus,
typically a microcontroller.
The device addressed by the master,
such as the MCP9843/98243.
Device receiving data from the bus.
A unique signal from master to initiate
serial interface with a slave.
A unique signal from the master to
terminate serial interface from a slave.
registers.
A receiver Acknowledges (ACK) the
reception of each byte by polling the
bus.
A receiver Not-Acknowledges (NAK) or
releases the bus to show End-of-Data
(EOD).
Communication is not possible
because the bus is in use.
The bus is in the idle state, both SDA
and SCL remain high.
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.
Standard
MCP9843/98243 SERIAL BUS
PROTOCOL DESCRIPTIONS
Description
mode
I
2
C
2
C™
B-FREE
compatible
.
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 MCP9843/98243
retain the previously selected register. Therefore, they
output data from the previously-specified register
(repeated pointer specification is not necessary).
4.1.2
The bus is controlled by a master device (typically a
microcontroller) that controls the bus access and
generates the Start and Stop conditions. The
MCP9843/98243 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
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. 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 MCP9843/98243 releases the bus.
All data transfers are ended by a Stop condition from
the master.
4.1.4
Following the Start condition, the host must transmit an
8-bit address byte to the MCP9843/98243. The
address for the MCP9843/98243 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
address transmitted in the serial bit stream must match
the selected address for the MCP9843/98243 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
FIGURE 4-1:
SDA
SCL
4-1).
Start
MASTER/SLAVE
START/STOP CONDITION
ADDRESS BYTE
MCP9843/98243
1 2 3
0 0
Address
Code
1 1 A2 A1 A0
Address Byte
Device Addressing.
4 5
DD
Address
‘1’ or GND ‘0’. The 7-bit
Slave
6
MCP9843/98243 Response
7
R/W
DS22153C-page 13
8
A
C
K
9