s-24c04c Seiko Instruments Inc., s-24c04c Datasheet - Page 21

• Manufacturer Part Number: s-24c04c
• Description: 2-wire Serial E2prom
• Manufacturer: Seiko Instruments Inc.

Rev.2.0
Using S-24C04C
1. Adding a pull-up resistor to SDA I/O pin and SCL input pin
2. Equivalent circuit of input and I/O pin
In consideration of I
The S-24C04C cannot transmit normally without using a pull-up resistor.
In case that the SCL input pin of the S-24C04C is connected to the Nch open drain output pin of the master device,
connect the SCL pin with a pull-up resistor. As well, in case the SCL input pin of the S-24C04C is connected to the tri-
state output pin of the master device, connect the SCL pin with a pull-up resistor in order not to set it in high
impedance. This prevents the S-24C04C from error caused by an uncertain output (high impedance) from the tri-state
pin when resetting the master device during the voltage drop.
Each pin (SCL, SDA) of the S-24C04C does not have a built-in pull-down or pull-up resistor. The WP, A1, A2 pin
includes a pull-down resistor. The SDA line has an open-drain output. The followings are equivalent circuits of the
pins.
_00_C
SDA
SCL
2
C-bus protocol function, the SDA I/O pins should be connected with a pull-up resistor.
Seiko Instruments Inc.
Figure 22 SCL Pin
Figure 23 SDA Pin
2-WIRE SERIAL E
S-24C04C
2
PROM
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