0.1μF+5V0.1μFC1+0.1μFC1-C2+0.1μFC2-400k?TINT1 T0 T5TOUT2500pF3k?R1 T0 R5R1 T0 R5VCCV+0.1μFV-0.1μF0.1μFC2-400k?TINT1 T0 T5+5V0.1μFC1+C1-C2+VCC0.1μFV+V-0.1μFMAX200-MAX209MAX211MAX213+5VMAX200-MAX209MAX211MAX213+5VTOUT50pF7k?ROUTEN (EN)RIN5k?ROUTEN (EN)RIN5k?0V (+5V)0V (+5V)0V (+5V)0V (+5V)SHDN (SHDN)MINIMUM SLEW-RATETEST CIRCUITNOTE: ( ) ARE FOR MAX213.SHDN (SHDN)MAXIMUM SLEW-RATETEST CIRCUITFigure 3. Transition Slew-Rate Test Circuit
S1C1+S2V+V+S5RL+C2+S6VCCGNDIL-C1S3S4C1-200kHzC3IL+C2C4RL-V-GNDVCCGNDS7C2-S8Figure 4. Dual Charge-Pump Diagram
RS-232 Receivers
The receivers convert RS-232 signals to CMOS logic output levels. Receiver outputs are inverting, maintaining compatibility with driver outputs. The guaranteed receiver input thresholds of +0.8V and +2.4V are significantly tighter than the ±3.0V threshold required by the EIA/TIA-232E specification. This allows receiver inputs to respond to TTL/CMOS logic levels and improves noise margin for RS-232 levels.
The MAX200–MAX209/MAX211/MAX213 guaranteed +0.8V threshold (+0.6V in shutdown for the MAX213)ensures that receivers shorted to ground have a logic 1output. Also, the 5kΩ input resistance to ground ensuresthat a receiver with its input left open also has a logic 1output.
Receiver inputs have approximately +0.5V hysteresis. This provides clean output transitions, even with slow rise and fall time input signals with moderate amounts of noise and ringing. In shutdown, the MAX213 receivers R4 and R5 have no hysteresis.
Integrated │ 6
MAX200–MAX209/MAX211/MAX213
MAX200 Pin Configuration/Typical Operating Circuit
+5V, RS-232 Transceiverswith 0.1μF External Capacitors
+5V INPUT0.1μF780.1μF+6.3V10110.1μF+16V12C1+C1-C2+C2-+5VVCC+5V TO +10VVOLTAGE DOUBLER+10V TO -10VVOLTAGE INVERTERV+90.1μF+6.3VV-130.1μF+16VTOP VIEW5T1IN400k?T1+5V400k?4T2IN+5V400k?TTL/CMOSINPUTS14T3IN+5V400k?15T4IN+5VT4T4OUT20T3T3OUT1RS-232OUTPUTST2T2OUT3T1OUT2T3OUT1T1OUT2T2OUT3T2IN4T1IN5GND6VCC7C1+8V+9C1-1020T4OUT19T5IN18N.C.MAX20017SHND16T5OUT15T4IN14T3IN13V-12C2-11C2+DIP/SO400k?19T5INT5T5OUT16N.C.18MAX200GND617SHDN Integrated │ 9
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