2.

Pin Descriptions

The descriptions of the pins are listed in Table 2-1.

Table 2-1. Pin Function Table

Name

5-Lead SOT23

4-Ball WLCSP

Function

SCL

1

B1

Serial Clock

GND

2

A2

Ground

SDA

3

B2

Serial Data

4

A1

Device Power Supply

WP(1)

5

—

Write-Protect

Note: 

1.

If the WP pin is not driven, it is internally pulled down to GND. In order to operate in a wide variety of

application environments, the pull-down mechanism is intentionally designed to be somewhat strong. Once

Microchip recommends connecting this pin to a known state whenever possible.

2.1

Serial Clock (SCL)

The SCL pin is used to provide a clock to the device and to control the flow of data to and from the device. Command

and input data present on the SDA pin is always latched in on the rising edge of SCL, while output data on the SDA

pin is clocked out on the falling edge of SCL. The SCL pin must either be forced high when the serial bus is idle or

pulled high using an external pull-up resistor.

2.2

Ground (GND)

ground.

2.3

Serial Data (SDA)

The SDA pin is an open-drain bidirectional input/output pin used to serially transfer data to and from the device. The

SDA pin must be pulled high using an external pull-up resistor (not to exceed 10 kΩ in value) and may be wire-ORed

with any number of other open-drain or open-collector pins from other devices on the same bus.

2.4

voltages may produce spurious results and should not be attempted.

2.5

Write-Protect (WP)

The write-protect input, when connected to GND, allows normal write operations. When the WP pin is connected

If the pin is left floating, the WP pin will be internally pulled down to GND. However, due to capacitive coupling that

may appear in customer applications, Microchip recommends always connecting the WP pin to a known state. When

using a pull‑up resistor, Microchip recommends using 10 kΩ or less.

AT24CSW01X/AT24CSW02X

Pin Descriptions

and its subsidiaries

Datasheet

DS20006396B-page 5