Datasheet
© 2011 Microchip Technology Inc. DS25095A-page 11
MCP9808
3.0 PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
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 the address bits and the Most Significant
bits (MSbs): A6, A5, A4, A3. This is illustrated in
Table 3-2.
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. The EP
may be connected to the system ground on the Printed
Circuit Board (PCB).
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
DD
Power Pin
9 — EP Exposed Thermal Pad (EP); must be connected to GND
TABLE 3-2: MCP9808 ADDRESS BYTE
Device Address Code Slave
Address
A6 A5 A4 A3 A2 A1 A0
MCP9808 0011x
(1)
xx
MCP9808
(2)
1001xxx
Note 1: User-selectable address is shown by ‘x’.
A2, A1 and A0 must match the
corresponding device pin configuration.
2: Contact factory for this address code.