S24CS02A datasheet(23/47 Pages) SII

23 / 47 page

2-WIRE CMOS SERIAL E2PROM

Rev.4.4_00

S-24CS01A/02A/04A/08A

Seiko Instruments Inc.

4. Acknowledge check

The I

2C-bus protocol includes an acknowledge check function as a handshake function to prevent a

communication error. This function allows detection of a communication failure during data communication

between the microprocessor and E

2PROM. This function is effective to prevent malfunction, so it is

recommended to perform an acknowledge check on the microprocessor side.

5. Built-in power-on-clear circuit

2PROMs have a built-in power-on-clear circuit that initializes the E2PROM. Unsuccessful initialization

may cause a malfunction. For the power-on-clear circuit to operate normally, the following conditions must

be satisfied for raising the power supply voltage.

5. 1 Raising power supply voltage

Raise the power supply voltage, starting at 0.2 V maximum, so that the voltage reaches the power supply

voltage to be used within the time defined by tRISE as shown in Figure 27.

For example, when the power supply voltage to be used is 5.0 V, tRISE is 200 ms as shown in Figure 28.

The power supply voltage must be raised within 200 ms.

0.2 V

VINIT (Max.)

tINIT

*2 (Max.)

tRISE (Max.)

Power supply voltage (VCC)

0 V

*1. 0 V means there is no difference in potential between the VCC pin and the

GND pin of the E

2PROM.

*2. tINIT is the time required to initialize the E

2PROM. No instructions are

accepted during this time.

Figure 27 Raising Power Supply Voltage

S24CS02A 数据表(PDF) 23 Page - Seiko Instruments Inc