Datasheet

© 2009 Microchip Technology Inc. DS22153C-page 11
MCP9843/98243
3.0 PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLES
3.1 Address Pins (A0, A1, A2)
These pins are device address input pins.
The address pins correspond to the Least Significant
bits (LSb) of address bits. The Most Significant bits
(MSb) (A6, A5, A4, A3). This is shown in Tab l e 3 - 2 .
The A0 Address pin is a multi-function pin. This input
pin is also used for high voltge input V
HV
to enable the
EEPROM Software Write Protect feature, see
Section 5.3.3 “Write Protection”.
All address pin have an internal pull-down resistors.
3.2 Ground Pin (GND)
The GND pin is the system ground pin.
3.3 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”).
3.4 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”).
3.5 Temperature Alert, Open-Drain
Output (Event)
The MCP9843/98243 temperature Event 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
“Event Output Configuration”).
3.6 Power Pin (V
DD
)
V
DD
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; they can
be connected to the same potential on the Printed Cir-
cuit Board (PCB). This provides better thermal conduc-
tion from the PCB to the die.
MCP9843/98243
Symbol Description
DFN, TDFN,
UDFN
TSSOP
1 1 A0 Slave Address and EEPROM Software Write Protect high voltage
input (V
HV
)
2 2 A1 Slave Address
3 3 A2 Slave Address
4 4 GND Ground
5 5 SDA Serial Data Line
6 6 SCL Serial Clock Line
7 7 Event Temperature Alert Output
88 V
DD
Power Pin
9 — EP Exposed Thermal Pad (EP); can be connected to GND.
TABLE 3-2: MCP9843/98243 ADDRESS
BYTE
Device Address Code Slave
Address
A6 A5 A4 A3 A2 A1 A0
Sensor 0 0 1 1
XXX
EEPROM 1 0 1 0
EEPROM
Write Protect
0110
Note: User-selectable address is shown by X.