PT7C4337WEX Pericom Semiconductor, PT7C4337WEX Datasheet - Page 14

• Manufacturer Part Number: PT7C4337WEX
• Description: IC REAL TIME CLK/CALENDAR 8-SOIC
• Manufacturer: Pericom Semiconductor
• Type: Clock/Calendar/Alarmr

Specifications of PT7C4337WEX

• Time Format: Binary
• Date Format: Binary
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Other names: PT7C4337WEXTR

Data Sheet
PT7C4337
2
Real-time Clock Module (I
C Bus)
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b) Data acknowledge response (ACK signal)
When transferring data, the receiver generates a confirmation response (ACK signal, low active) each time an 8-bit data segment
is received. If there is no ACK signal from the receiver, it indicates that normal communication has not been established. (This
does not include instances where the master device intentionally does not generate an ACK signal.)
Immediately after the falling edge of the clock pulse corresponding to the 8th bit of data on the SCL line, the transmitter releases
the SDA line and the receiver sets the SDA line to low (= acknowledge) level.
SCL from Master
8
9
2
1
SDA from transmitter
Release SDA
(sending side)
Low active
SDA from receiver
(receiving side)
ACK signal
After transmitting the ACK signal, if the Master remains the receiver for transfer of the next byte, the SDA is released at the
falling edge of the clock corresponding to the 9th bit of data on the SCL line. Data transfer resumes when the Master becomes the
transmitter.
When the Master is the receiver, if the Master does not send an ACK signal in response to the last byte sent from the slave, that
indicates to the transmitter that data transfer has ended. At that point, the transmitter continues to release the SDA and awaits a
STOP condition from the Master.
PT0205(08/09)
Ver: 4
14