Datasheet

MB85RC256V

NP501-00019-2v0-E

2013.5 2/2

PIN ASSIGNMENT

BLOCK DIAGRAM

The MB85RC256V has the two-wire serial interface; the

C bus, and operates as a slave device.

The I

C bus defines communication roles of “master” and “slave” devices, with the master side

holding the authority to initiate control. Furthermore, the I

C bus connection is possible

where a single master device is connected to multiple slave devices in a party-line configuration.

In this case, it is necessary to assign a unique device address to the slave device, the master side

starts communication after specifying the slave to communicate by addresses.

Pin No. Pin name Description

1 to 3 A0 to A2

Device Address pins

MB85RC256V can be connected to the same data bus up to 8 devices. Device addresses are

used in order to identify each of these devices. Connect these pins to VDD pin or VSS pin

externally. Only if the combination of VDD and VSS pin matches a Device Address Code

inputted from the SDA pin, the device operates. In the open pin state, A0, A1 and A2 are

internally pulled-down and recognized as the "L" level.

4 VSS Ground pin

5 SDA

Serial Data I/O pin

This is an I/O pin which performs bidirectional communication for both memory address and

writing/reading data. It is possible to connect multiple devices. It is an open drain output, so a

pull-up resistor is required to be connected to the external circuit.

6 SCL

Serial Clock pin

This is a clock input pin for input/output serial data. Data is sampled on the rising edge of the

clock and output on the falling edge.

7 WP

Write Protect pin

When Write Protect pin is the "H" level, writing operation is disabled. When Write Protect pin

is the "L" level, the entire memory region can be overwritten. Reading operation is always

enabled regardless of Write Protect pin input level. The Write Protect pin is internally pulled

down to VSS pin, and that is recognized as the "L" level (write enabled) when the pin is the

open state.

8 VDD Supply Voltage pin

(TOP VIEW)

(FPT-8P-M02)

(FPT-8P-M08)