ST24FC21 STMICROELECTRONICS [STMicroelectronics], ST24FC21 Datasheet - Page 17

• Manufacturer Part Number: ST24FC21
• Description: 1 Kbit x8 Dual Mode Serial EEPROM for VESA PLUG & PLAY
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Figure 13. Recommended Schematic for VESA 2.0 Specification
low during this time, the ST24xy21 terminate the
data transfer and switches to a standby state.
NOTE CONCERNING THE POWER SUPPLY
VOLTAGE IN THE VESA 2.0 SPECIFICATION
According to the VESA 2.0 specification, the
ST24xy21 can be supplied by either the MONITOR
or by the HOST (using +5V on the VGA cable pin
9) power supply. The easyest way to implement this
is to use 2 diodes as described in the following
VSync
SDA
SCL
+5V
HOST
VGA Cable
ST24LC21B, ST24LW21, ST24FC21, ST24FC21B, ST24FW21
15
12
14
9
schematic. The ST24xy21 supply voltage will be
decreased by 0.6V, which is the diode forward
voltage drop, and will be below 4.5V. Nevertheless,
the ST24xy21 remains operational and no input will
be damaged if the applied voltage on any input
complies with the Absolute Maximum Ratings val-
ues.
Under this condition, the threshold voltage of the
Schmitt-Trigger (pin 7) will be decreased (as in
Table 6).
MONITOR
47k
SCL
SDA
VCLK
V CC
V SS
AI01749
+5V Monitor
100nF
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