2-WIRE CMOS SERIAL E2PROM
S-24CS01A/02A/04A/08A
Rev.4.4_00
4. Acknowledge check
The I2C-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 E2PROM. 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
E2PROMs 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.
tRISE (Max.)
Power supply voltage (VCC)
VINIT (Max.)
0.2 V
0 V*1
tINIT*2 (Max.)
*1. 0 V means there is no difference in potential between the VCC pin and the
GND pin of the E2PROM.
*2. tINIT is the time required to initialize the E2PROM. No instructions are
accepted during this time.
Figure 27 Raising Power Supply Voltage
23
Seiko Instruments Inc.
SII [ SEIKO INSTRUMENTS INC ]
