DS14C335
Application Information
(Continued)
mixed power supplied +3V/+5V applications. The Driver In-
put (DIN) and ShutDown (SD) input pins can directly accept
full +5V levels without the need for any external components.
The Receiver Output (ROUT) is specified at 2.4V minimum
while sourcing 1 mA. This level is compatible with standard
TTL thresholds. For a complete discussion on “Interopera-
tion of the DS14C335 with +5V UARTs” please see National
Application Note AN-876.
POWER DISSIPATION IN REAL RS-232 APPLICATIONS
The DS14C335 DC-DC Convertor uses special circuitry that
helps limit the increase in power supply current as frequency
increases. A complete description of power dissipation and
calculations for RS-232 applications can be found in Na-
tional Application Note AN-914 titled “Understanding Power
Requirements in RS-232 Applications”. Typical performance
curves are also located in this datasheet for quick reference.
Typical Performance Characteristics
Supply Current vs Frequency
vs Driver Loads
Supply Current vs Frequency
vs Driver Loads
DS011734-12
DS011734-13
Supply Power vs Data Rate
Supply Current vs
Frequency (Receiver)
DS011734-14
DS011734-15
7
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