ICL3232ECBN Intersil, ICL3232ECBN Datasheet - Page 15

• Manufacturer Part Number: ICL3232ECBN
• Description: IC TXRX RS-232 3-5.5V ESD 16SOIC
• Manufacturer: Intersil
• Type: Transceiverr

Specifications of ICL3232ECBN

• Number Of Drivers/receivers: 2/2
• Protocol: RS232
• Voltage - Supply: 3 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

ICL3222E, ICL3241E
RECEIVER
ICL3241E and ICL3243E monitor receivers remain
active even during manual power-down and forced
receiver disable, making them extremely useful for
Ring Indicator monitoring. Standard receivers driving
powered down peripherals must be disabled to
prevent current flow through the peripheral’s
protection diodes (see Figures 2 and 3). This renders
them useless for wake up functions, but the
corresponding monitor receiver can be dedicated to
this task as shown in Figure 3.
Low Power Operation
These 3V devices require a nominal supply current of
0.3mA, even at V
(not in power-down mode). This is considerably less
than the 5mA to 11mA current required by comparable
5V RS-232 devices, allowing users to reduce system
power simply by switching to this new family.
Pin Compatible Replacements for 5V
Devices
The ICL3221E, ICL3222E, ICL3232E are pin compatible
with existing 5V RS-232 transceivers - See the
“Features” section on page 1 for details.
This pin compatibility coupled with the low I
wide operating supply range, make the ICL32xxE
potential lower power, higher performance drop-in
replacements for existing 5V applications. As long as
the ±5V RS-232 output swings are acceptable, and
transmitter input pull-up resistors aren’t required, the
IICL32xxE should work in most 5V applications.
When replacing a device in an existing 5V application,
it is acceptable to terminate C
the “Typical Operating Circuits” on page 2.
Nevertheless, terminate C
slightly better performance results from this
configuration.
PRESENT
SIGNAL
RS-232
INPUT?
FIGURE 1. INVERTING RECEIVER CONNECTIONS
N/A
N/A
N/A
N/A
AT
-25V ≤ V
ICL3221E, ICL3222E, ICL3223E, ICL3232E, ICL3241E, ICL3243E
FORCEOFF
RIN
OR SHDN
R
GND
INPUT
V
XIN
CC
≤ +25V
H
H
L
L
CC
= 5.5V, during normal operation
FORCEON
5kΩ
INPUT
15
3
N/A
N/A
N/A
N/A
TABLE 2. POWER-DOWN AND ENABLE LOGIC TRUTH TABLE
to GND if possible, as
3
to V
GND ≤ V
INPUT
CC
EN
R
H
H
L
L
XOUT
as shown on
ROUT
TRANSMITTER
CC
≤ V
OUTPUTS
High-Z
High-Z
Active
Active
CC
and
RECEIVER
OUTPUTS
High-Z
High-Z
Active
Active
Power-Down Functionality
(Except ICL3232E)
The already low current requirement drops
significantly when the device enters power-down
mode. In power-down, supply current drops to 1µA,
because the on-chip charge pump turns off (V+
collapses to V
transmitter outputs three-state. Inverting receiver
outputs may or may not disable in power-down; refer
to Table 2 for details. This micro-power mode makes
these devices ideal for battery powered and portable
applications.
Software Controlled (Manual) Power-Down
Most devices in the ICL32xxE family provide pins that
allow the user to force the IC into the low power,
standby state.
On the ICL3222E and ICL3241E, the power-down
control is via a simple shutdown (SHDN) pin. Driving
this pin high enables normal operation, while driving it
low forces the IC into its power-down state. Connect
SHDN to V
Note that all the receiver outputs remain enabled
during shutdown (see Table 2). For the lowest power
consumption during power-down, the receivers should
also be disabled by driving the EN input high (see next
section, and Figures 2 and 3).
The ICL3221E, ICL3223E, and ICL3243E utilize a two
pin approach where the FORCEON and FORCEOFF
inputs determine the IC’s mode. For always enabled
operation, FORCEON and FORCEOFF are both strapped
high. To switch between active and power-down
modes, under logic or software control, only the
FORCEOFF input need be driven. The FORCEON state
isn’t critical, as FORCEOFF dominates over FORCEON.
Nevertheless, if strictly manual control over power-
down is desired, the user must strap FORCEON high to
disable the automatic power-down circuitry. ICL3243E
inverting (standard) receiver outputs also disable when
the device is in manual power-down, thereby
eliminating the possible current path through a
shutdown peripheral’s input protection diode (see
Figures 2 and 3).
OUTPUTS
(NOTE 7)
R
Active
Active
Active
Active
OUTB
CC
CC
if the power-down function isn’t needed.
, V- collapses to GND), and the
INVALID
OUTPUT
N/A
N/A
N/A
N/A
Normal Operation with
Receiver Disabled
Manual Power-Down
Manual Power-Down with
Normal Operation
Receiver Disabled
OPERATION
MODE OF
February 22, 2010
FN4910.21