max221e Maxim Integrated Products, Inc., max221e Datasheet
max221e
Available stocks
Related parts for max221e
max221e Summary of contents
Page 1
... The MAX221E wakes up and drives the INVALID pin high when an active RS-232 cable is con- nected, signaling the host that a peripheral is connected to the communications port. The MAX221E is available in a 16-pin SSOP package as well as a 16-pin TSSOP that uses 50% less board space than a 16-pin SO. Maintenance/Diagnostic Ports ...
Page 2
... TSSOP (derated 6.7mW/°C above +70°C) .......533mW 16-Pin SSOP (derated 7.1mW/°C above +70°C) .........571mW Operating Temperature Range MAX221EC_ _. ....................................................0°C to +70°C + 0.3V) MAX221EE_ _ ..................................................-40°C to +85°C CC Maximum Junction Temperature .................................... +150°C Storage Temperature Range ........................... -65°C to +150°C + 0.3V) Lead Temperature (soldering, 10sec) ............................ +300°C ...
Page 3
ESD-Protected, +5V, 1µA, Single RS-232 ELECTRICAL CHARACTERISTICS (continued +5V ±10%, C1–C4 = 0.1µ PARAMETER SYMBOL RECEIVER INPUT Input Voltage Range Input Threshold Low Input Threshold High Input Hysteresis Input Resistance TRANSMITTER OUTPUT Output Voltage ...
Page 4
ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdown (V = +5V, 250kbps data rate, 0.1µF capacitors, transmitter loaded with 3k and C CC TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE 20kbps 120kbps 4 250kbps 2 0 250kbps ...
Page 5
... Figure 3 shows the input levels and timing diagram for AutoShutdown operation. A device or another system with AutoShutdown con- nected to the MAX221E may need time to wake up. Figure 4 shows a circuit that forces the transmitter on for 100ms, allowing enough time for the other system to realize that the MAX221E is awake. If the other system transmits valid RS-232 signals within that time, the RS-232 ports on both systems remain enabled ...
Page 6
... INVALID R INVALID IS AN INTERNALLY GENERATED SIGNAL USED BY AUTOSHUTDOWN LOGIC AND APPEARS AS AN OUTPUT. POWER DOWN IS ONLY AN INTERNAL SIGNAL. IT CONTROLS THE OPERATIONAL STATUS OF THE TRANSMITTER AND POWER SUPPLIES. Figure 2c. AutoShutdown Logic TO MAX221E Table 2. INVALID Truth Table POWER SUPPLY 30µs COUNTER INVALID R RS-232 SIGNAL PRESENT ...
Page 7
... RS-232 products can latch and must be powered down to remove latchup. INVALID ESD protection can be tested in various ways; the trans- REGION mitter output and receiver input of the MAX221E are characterized for protection to the following limits: 1) ±15kV using the Human Body Model 2) ±8kV using the Contact-Discharge Method specified in IEC 1000-4-2 3) ± ...
Page 8
ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdown 1500 C D DISCHARGE CHARGE-CURRENT RESISTANCE LIMIT RESISTOR HIGH STORAGE VOLTAGE 100pF CAPACITOR DC SOURCE Figure 5a. Human Body ESD Test Model I 100 ...
Page 9
... Figure 7 shows the transmitter output when exiting shutdown mode. The transmitter is loaded with 3k parallel with 1000pF. The transmitter output displays no ringing or undesirable transients as the MAX221E comes out of shutdown. The MAX221E maintains the RS-232 ±5.0V minimum transmitter output voltage even at high data rates. ...
Page 10
ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdown 5V/div 5V/div 5V/div 2 s/div Figure 9. Loopback Test Result at 120kbps ___________________Chip Information TRANSISTOR COUNT: 157 10 ______________________________________________________________________________________ TIN 5V/div 5V/div TOUT ROUT 5V/div Figure 10. Loopback Test Result at ...
Page 11
ESD-Protected, +5V, 1µA, Single RS-232 ______________________________________________________________________________________ Transceiver with AutoShutdown Package Information 11 ...
Page 12
ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdown Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are Maxim cannot assume responsibility for use of any ...