MAX3233ECWP-T Maxim Integrated, MAX3233ECWP-T Datasheet - Page 7

• Manufacturer Part Number: MAX3233ECWP-T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3233E, MAX3235Er

Specifications of MAX3233ECWP-T

• Data Rate: 250 Kbps
• Operating Supply Voltage: 3.3 V
• Supply Current: 1 mA
• Operating Temperature Range: 0 C to + 70 C
• Mounting Style: SMD/SMT
• Function: Transceiver
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Number Of Drivers: 2
• Number Of I/os: 8
• Number Of Receivers: 2
• Propagation Delay Time Ns: 0.25 us
• Shutdown: Yes

Table 1. Output Control Truth Table
X = Don’t care
* INVALID connected to FORCEON
** INVALID connected to FORCEON and FORCEOFF
Figure 2c. AutoShutdown Plus Logic
applied to any RS-232 receiver or transmitter input. As a
result, the system saves power without changes to the
existing BIOS or operating system.
Figures 2a and 2b depict invalid and valid RS-232
receiver voltage levels. INVALID indicates the receiver
input’s condition, and is independent of FORCEON and
FORCEOFF states. Figure 2 and Tables 1 and 2 sum-
marize the operating modes. FORCEON and FORCE-
±15kV ESD-Protected, 1µA, 250kbps, 3.3V/5V, Dual
Shutdown (Forced Off)
Normal Operation (Forced On)
Normal Operation
(AutoShutdown Plus)
Shutdown
(AutoShutdown Plus)
Normal Operation
Normal Operation
Shutdown
Normal Operation
(AutoShutdown)
Shutdown (AutoShutdown)
*AUTOSHDN IS ONLY AN INTERNAL SIGNAL.
R_IN
T_IN
OPERATION STATUS
RS-232 Transceivers with Internal Capacitors
DETECT
DETECT
EDGE
EDGE
_______________________________________________________________________________________
FORCEON
FORCEON
INVALID*
INVALID*
INVALID*
INVALID*
INVALID*
FORCEOFF
X
1
0
0
TIMER
30sec
S
R
AUTOSHDN*
FORCEOFF
INVALID**
INVALID**
0
1
1
1
1
1
1
RECEIVER
LEVEL
VALID
OFF override AutoShutdown Plus circuitry. When nei-
ther control is asserted, the IC selects between these
states automatically based on the last receiver or trans-
mitter input edge received.
When shut down, the device’s charge pumps turn off,
V+ is pulled to V
transmitter outputs are high impedance. The time
required to exit shutdown is typically 100µs (Figure 7).
Figure 2d. Power-Down Logic
Yes
Yes
No
No
X
X
X
X
X
*
POWERDOWN IS ONLY AN INTERNAL SIGNAL. IT CONTROLS THE OPERATIONAL
STATUS OF THE TRANSMITTERS AND THE POWER SUPPLIES.
AUTOSHDN
FORCEOFF
FORCEON
Rx or Tx EDGE
WITHIN 30sec
Yes
Yes
No
No
X
X
X
X
X
CC
, V- is pulled to ground, and the
T_OUT
High-Z
High-Z
High-Z
High-Z
Active
Active
Active
Active
Active
POWERDOWN*
R_OUT
Active
Active
Active
Active
Active
Active
Active
Active
Active
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