ADM202EARN Analog Devices Inc, ADM202EARN Datasheet - Page 13

• Manufacturer Part Number: ADM202EARN
• Description: RS-232 LINE DRIVER/RECEIVER, DRIVER/RECEIVER, 4.5 TO 5.5 VSUPPLY VOLTAGE, 16 LEAD, NARROW SOIC, ADM202, RS-232 INTERFACE
• Manufacturer: Analog Devices Inc
• Type: Transceiverr

Specifications of ADM202EARN

• Rohs Status: RoHS non-compliant
• Number Of Drivers/receivers: 2/2
• Protocol: RS232
• Voltage - Supply: 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Data Rate: 230Kbps
• Interface Circuit Standard 1: EIA/TIA-232-E/RS-232
• Number Of Receivers: 2
• Number Of Transmitters: 2
• Number Of Transceivers: 2
• Data Transmission Topology: Point-to-Point
• Receiver Signal Type: Single-Ended
• Transmitter Signal Type: Single-Ended
• Single Supply Voltage (typ): 5V
• Single Supply Voltage (min): 4.5V
• Single Supply Voltage (max): 5.5V
• Dual Supply Voltage (typ): Not RequiredV
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Supply Current: 18mA
• Power Supply Requirement: Single
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 16
• Package Type: SOIC N
• Lead Free Status / Rohs Status: Not Compliant

RADIATED EMISSIONS
Radiated emissions are measured at frequencies in excess of
30 MHz. RS-232 outputs are designed for operation at high
baud rates, while driving cables can radiate high frequency EM
energy. The previously described causes of conducted emissions
can also cause radiated emissions. Fast RS-232 output transitions
can radiate interference, especially when lightly loaded and
driving unshielded cables. Charge-pump devices are also prone
to radiating noise due to the high frequency oscillator and the
high voltages being switched by the charge pump. The move
toward smaller capacitors to conserve board space has resulted
in higher frequency oscillators in the charge-pump design,
causing higher levels of conducted and radiated emissions.
The RS-232 outputs on the ADM202E feature a controlled slew
rate to minimize the level of radiated emissions, yet they are fast
enough to support data rates of up to 230 kBaud.
Figure 27 shows radiated emissions vs. frequency. The levels of
emissions are well within specifications without the need for
additional shielding or filtering components. The ADM202E
80
70
60
50
40
30
20
10
0
0.3
Figure 25. ADM202E Conducted Emissions
0.6
LOG FREQUENCY (MHz)
1
3
6
10
30
LIMIT
Rev. C | Page 13 of 16
was operated at maximum baud rates and configured like a
typical RS-232 interface. Testing for radiated emissions was
carried out in a shielded anechoic chamber.
80
70
60
50
40
30
20
10
0
START 30.0MHz
Figure 27. ADM202E Radiated Emissions vs. Frequency
DUT
RADIATED NOISE
TURNTABLE
Figure 26. Radiated Emissions Test Setup
ADJUSTABLE
ANTENNA
ADM202E/ADM1181A
STOP 200.0MHz
TO
RECEIVER
LIMIT