DS14C335MSA National Semiconductor, DS14C335MSA Datasheet - Page 7

• Manufacturer Part Number: DS14C335MSA
• Description: IC, RS-232 TRANSCEIVER, 3.6V, SSOP-28
• Manufacturer: National Semiconductor

Specifications of DS14C335MSA

• Device Type: Driver / Receiver
• Ic Interface Type: RS232
• No. Of Drivers: 3
• Supply Voltage Range: 3V To 3.6V
• Driver Case Style: SSOP
• No. Of Pins: 28
• Operating Temperature Range: 0°C To +70°C
• Package: 28SSOP-EIAJ
• Data Transmission Topology: Point-to-Point
• Interface Standards: EIA/TIA-232-E|V.28
• Data Rate: 0.128 Mbps
• Function: Line Transmitter/Receiver
• Number Of Receivers: 5
• Number Of Transmitters: 3
• Transmitter Signal Type: Single-Ended
• Transmitter Communication Type: RS-232
• Typical Single Supply Voltage: 3.3 V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Application Information
vertor also provides a larger signal swing (higher at RS-232
standard data rates) which translates to more noise margin
for the rejection of ground potential differences, induced
noise, and crosstalk compared to other DC-DC convertor
schemes which only provide limited signal swing and limited
noise margin.
DC-DC CONVERTOR CAPACITORS
The use of polarized capacitors is not required. However, if
they are used, the polarity indicated in the DS14C335 Func-
tional Diagram must be honored for proper operation. Sur-
face mount capacitors or ceramic capacitors may be used,
however, for optimal efficiency, capacitors with a low effec-
tive series resistance (ESR) should be used. Values in the
low Ohms(Ω) is normally acceptable.
INTEROPERATION WITH +5V UARTS
The DS14C335 provides full RS-232 driver output levels and
a single chip solution for the popular 9-pin defacto serial port.
This device may be used in either pure +3V applications or
Typical Performance Characteristics
Supply Current vs Frequency
Supply Power vs Data Rate
vs Driver Loads
(Continued)
01173414
01173412
7
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.
Supply Current vs Frequency
Frequency (Receiver)
Supply Current vs
vs Driver Loads
01173413
01173415
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