1
FN6003.3
ICL3237
1 Microamp Supply-Current, +3V to +5.5V,
1Mbps, RS-232 Transmitters/Receivers
The Intersil ICL3237 contains 3.0V to 5.5V powered RS-232
transmitters/receivers which meet ElA/TIA-232 and
V.28/V.24 specifications, even at V
CC
= 3.0V. Targeted
applications are cell phones, PDAs, Palmtops, and notebook
and laptop computers where the low operational, and even
lower standby, power consumption is critical. Efficient on-
chip charge pumps, coupled with manual powerdown
function, reduce the standby supply current to a 1
A trickle.
Small footprint packaging, and the use of small, low value
capacitors ensure board space savings as well. Data rates
greater than 1Mbps (MBAUD = V
CC
) are guaranteed at
worst case load conditions. This family is fully compatible
with 3.3V only systems, mixed 3.3V and 5.0V systems, and
5.0V only systems.
The ICL3237 is a 5 driver, 3 receiver device that also
includes a noninverting always-active receiver for "wake-up"
capability.
Table 1 summarizes the features of the device represented
by this data sheet, while Application Note AN9863
summarizes the features of each device comprising the
ICL32XX 3V family.
Features
15kV ESD Protected (Human Body Model)
Drop in Replacement for MAX3237
Meets EIA/TIA-232 and V.28/V.24 Specifications at 3V
Latch-Up Free
On-Chip Voltage Converters Require Only Four External
Capacitors
Manual Powerdown Features
Flow Through Pinout
Receiver Hysteresis For Improved Noise Immunity
Pin Selectable Data Rate
Guaranteed Minimum Data Rate . . . . . . . 250kbps/1Mbps
Guaranteed Minimum Slew Rate . . . . . . . 6V/
s or 24V/
s
Wide Power Supply Range . . . . . . . Single +3V to +5.5V
Low Supply Current in Powerdown State. . . . . . . . . . .1
A
Pb-Free Plus Anneal Available (RoHS Compliant)
Applications
Any System Requiring RS-232 Communication Ports
- Battery Powered, Hand-Held, and Portable Equipment
- Laptop Computers, Notebooks, Palmtops
- Modems, Printers and other Peripherals
- Digital Cameras
- Cellular/Mobile Phone
Related Literature
Technical Brief TB363 "Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
(SMDs)"
AN9863 "3V to +5.5V, 250k-1Mbps, RS-232
Transmitters/Receivers"
TABLE 1. SUMMARY OF FEATURES
PART
NUMBER
NO. OF
Tx.
NO. OF
Rx.
NO. OF
MONITOR Rx.
(R
OUTB
)
(NOTE 1)
DATA
RATE
(kbps)
Rx. ENABLE
FUNCTION?
READY
OUTPUT?
MANUAL
POWER-
DOWN?
AUTOMATIC
POWERDOWN
FUNCTION?
ICL3237
5
3
1
250/1000
YES
NO
YES
NO
NOTE:
1. Data rate is selectable via the MBAUD pin.
Data Sheet
October 21, 2005
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2001-2002, 2004-2005. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
2
Pinout
ICL3237 (SSOP)
TOP VIEW
C2+
GND
C2-
V-
T1
OUT
T2
OUT
T3
OUT
R1
IN
R2
IN
R3
IN
T5
OUT
EN
SHDN
C1+
V
CC
C1-
T1
IN
T2
IN
R1
OUT
T4
IN
R3
OUT
T5
IN
R1
OUTB
MBAUD
V+
T3
IN
R2
OUT
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
T4
OUT
Ordering Information
PART NO.
PART
MARKING
TEMP.
RANGE
(C)
PACKAGE
PKG.
DWG. #
ICL3237CA
ICL3237CA
0 to 70
28 Ld SSOP M28.209
ICL3237CAZ
(See Note)
ICL3237CAZ
0 to 70
28 Ld SSOP
(Pb-free)
M28.209
ICL3237IA
ICL3237IA
-40 to 85 28 Ld SSOP M28.209
ICL3237IAZ
(See Note)
ICL3237IAZ
-40 to 85 28 Ld SSOP
(Pb-free)
M28.209
*Add "-T" suffix to part number for tape and reel packaging.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are RoHS compliant and
compatible with both SnPb and Pb-free soldering operations. Intersil
Pb-free products are MSL classified at Pb-free peak reflow
temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.
Pin Descriptions
PIN
FUNCTION
V
CC
System Power Supply Input (3.0V to 5.5V).
V+
Internally Generated Positive Transmitter Supply (+5.5V).
V-
Internally Generated Negative Transmitter Supply (-5.5V).
GND
Ground Connection.
C1+
External Capacitor (Voltage Doubler) is connected to this lead.
C1-
External Capacitor (Voltage Doubler) is connected to this lead.
C2+
External Capacitor (Voltage Inverter) is connected to this lead.
C2-
External Capacitor (Voltage Inverter) is connected to this lead.
T
IN
TTL/CMOS Compatible Transmitter Inputs.
T
OUT
RS-232 level (nominally
5.5V) transmitter outputs.
R
IN
RS-232 Compatible Receiver Inputs.
R
OUT
TTL/CMOS Level Receiver Outputs.
R
OUTB
TTL/CMOS Level, Noninverting, Always Enabled Receiver Output.
EN
Active Low Receiver Enable Control; doesn't disable R
OUTB
output.
SHDN
Active Low Input to Shutdown Transmitters and On-Board Power Supply, to place device in low power mode.
MBAUD
Input Low selects 250kbps data rate, and input high selects 1Mbps data rate.
ICL3237
3
Typical Operating Circuit
ICL3237
26
V
CC
T1
OUT
T2
OUT
T3
OUT
T1
IN
T2
IN
T3
IN
T
1
T
2
T
3
0.1
F
+
0.1
F
+
0.1
F
24
23
5
6
22
7
28
25
27
4
V+
V-
C1+
C1-
C2+
C2-
+
0.1
F
1
3
R1
OUT
R1
IN
8
5k
R2
OUT
R2
IN
9
20
5k
R3
OUT
R3
IN
11
18
5k
21
R1
OUTB
C
1
C
2
+ C
3
C
4
EN
SHDN
13
GND
14
+3.3V
+
0.1
F
16
2
V
CC
TTL/CMOS
LOGIC LEVELS
RS-232
LEVELS
RS-232
LEVELS
R
1
R
2
R
3
15
MBAUD
TO CONTROL LOGIC
+
C
3
(OPTIONAL CONNECTION, NOTE)
NOTE: THE NEGATIVE TERMINAL OF C
3
CAN BE CONNECTED TO EITHER V
CC
OR GND.
T4
OUT
T5
OUT
T4
IN
T5
IN
T
4
T
5
19
10
17
12
ICL3237
4
Absolute Maximum Ratings
Thermal Information
V
CC
to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6V
V+ to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7V
V- to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +0.3V to -7V
V+ to V- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14V
Input Voltages
T
IN
, EN, SHDN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6V
MBAUD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to V
CC
+0.3V
R
IN
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25V
Output Voltages
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.2V
R
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to V
CC
+0.3V
Short Circuit Duration
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . See Specification Table
Thermal Resistance (Typical, Note 2)
JA
(
o
C/W)
28 Ld SSOP Package . . . . . . . . . . . . . . . . . . . . . . .
100
Moisture Sensitivity (see Technical Brief TB363)
All Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Level 1
Maximum Junction Temperature (Plastic Package) . . . . . . . 150
o
C
Maximum Storage Temperature Range . . . . . . . . . -65
o
C to 150
o
C
Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . 300
o
C
(Lead Tips Only)
Operating Conditions
Temperature Range
ICL3237C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
o
C to 70
o
C
ICL3237I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40
o
C to 85
o
C
CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
2.
JA
is measured with the component mounted on a low effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
Electrical Specifications
Test Conditions: V
CC
= 3V, C
1
- C
4
= 0.22
F; V
CC
= 3.15V to 5.5V, C
1
- C
4
= 0.1
F, Unless Otherwise
Specified. Typicals are at T
A
= 25
o
C
PARAMETER
TEST CONDITIONS
TEMP
(
o
C)
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS
Supply Current,
Powerdown Disabled
All Outputs Unloaded, V
CC
= 3.15V, SHDN = V
CC
25
-
0.3
1.0
mA
Supply Current, Powerdown
SHDN = GND
25
-
1.0
10
A
LOGIC AND TRANSMITTER INPUTS AND RECEIVER OUTPUTS
Input Logic Threshold Low
T
IN
, EN, SHDN, MBAUD
Full
-
-
0.8
V
Input Logic Threshold High
T
IN
, EN, SHDN,
MBAUD
V
CC
= 3.3V
Full
2.0
-
-
V
V
CC
= 5.0V
Full
2.4
-
-
V
Transmitter Input Hysteresis
25
-
0.5
-
V
Input Leakage Current
T
IN
, EN, SHDN, MBAUD
Full
-
0.01
1.0
A
Output Leakage Current
EN = V
CC
(Receivers Disabled)
Full
-
0.05
10
A
Output Voltage Low
I
OUT
= 1.6mA
Full
-
-
0.4
V
Output Voltage High
I
OUT
= -1.0mA
Full
V
CC
-0.6 V
CC
-0.1
-
V
RECEIVER INPUTS
Input Voltage Range
Full
-25
-
25
V
Input Threshold Low
V
CC
= 3.3V
25
0.6
1.2
-
V
V
CC
= 5.0V
25
0.8
1.5
-
V
Input Threshold High
V
CC
= 3.3V to 5.0V
25
-
1.6
2.4
V
Input Hysteresis
25
-
0.3
-
V
Input Resistance
25
3
5
7
k
TRANSMITTER OUTPUTS
Output Voltage Swing
All Transmitter Outputs Loaded with 3k
to Ground
Full
5.0
5.4
-
V
ICL3237
5
Output Resistance
V
CC
= V+ = V- = 0V, Transmitter Output =
2V
Full
300
10M
-
Output Short-Circuit Current
Full
-
35
60
mA
Output Leakage Current
V
OUT
=
12V, V
CC
= 0V or 3V to 5.5V, SHDN = GND
Full
-
-
25
A
TIMING CHARACTERISTICS
Maximum Data Rate
R
L
= 3k
,
One
Transmitter Switching
C
L
= 1000pF
MBAUD = GND
Full
250
700
-
kbps
V
CC
= 3V to 4.5V,
C
L
= 250pF
MBAUD = V
CC
Full
1000
1700
-
kbps
V
CC
= 4.5V to 5.5V,
C
L
= 1000pF
MBAUD = V
CC
Full
1000
1100
-
kbps
Receiver Propagation Delay
Receiver Input to
Receiver Output,
C
L
= 150pF
t
PHL
25
-
0.15
-
s
t
PLH
25
-
0.15
-
s
Receiver Output Enable Time
Normal Operation
25
-
200
-
ns
Receiver Output Disable Time
Normal Operation
25
-
200
-
ns
Transmitter Skew
t
PHL
- t
PLH
(Note 3)
MBAUD = GND
25
-
100
ns
MBAUD = V
CC
, V
CC
= 3.0V
25
-
25
ns
Receiver Skew
t
PHL
- t
PLH
, C
L
= 150pF
25
-
50
-
ns
Transition Region Slew Rate
V
CC
= 3.3V,
R
L
= 3k
to 7k
,
Measured From 3V to
-3V or -3V to 3V
C
L
= 150pF to 1000pF MBAUD = GND
25
6
17
30
V/
s
MBAUD = V
CC
25
24
40
150
V/
s
C
L
= 150pF to 2500pF MBAUD = GND
25
4
12
30
V/
s
ESD PERFORMANCE
RS-232 Pins (T
OUT
, R
IN
)
Human Body Model
25
-
15
-
kV
IEC61000-4-2 Contact Discharge
25
-
8
-
kV
IEC61000-4-2 Air Gap Discharge
25
-
>
8
-
kV
All Other Pins
Human Body Model
25
-
2.5
-
kV
NOTE:
3. Skew is measured at the input switching points (1.4V).
Electrical Specifications
Test Conditions: V
CC
= 3V, C
1
- C
4
= 0.22
F; V
CC
= 3.15V to 5.5V, C
1
- C
4
= 0.1
F, Unless Otherwise
Specified. Typicals are at T
A
= 25
o
C (Continued)
PARAMETER
TEST CONDITIONS
TEMP
(
o
C)
MIN
TYP
MAX
UNITS
ICL3237
6
Detailed Description
The ICL3237 operates from a single +3V to +5.5V supply,
guarantees a 1Mbps minimum data rate, requires only four
small external 0.1
F capacitors, features low power
consumption, and meets all EIA/TIA-232 and V.28
specifications. The circuit is divided into three sections: The
charge pump, the transmitters, and the receivers.
Charge-Pump
Intersil's new ICL32XX family utilizes regulated on-chip dual
charge pumps as voltage doublers, and voltage inverters to
generate
5.5V transmitter supplies from a V
CC
supply as
low as 3.0V. This allows these devices to maintain RS-232
compliant output levels over the
10% tolerance range of
3.3V powered systems. The efficient on-chip power supplies
require only four small, external 0.1
F capacitors for the
voltage doubler and inverter functions at V
CC
= 3.3V. See
the "Capacitor Selection" section, and Table 3 for capacitor
recommendations for other operating conditions. The charge
pumps operate discontinuously (i.e., they turn off as soon as
the V+ and V- supplies are pumped up to the nominal
values), resulting in significant power savings.
Transmitters
The transmitters are proprietary, low dropout, inverting
drivers that translate TTL/CMOS inputs to EIA/TIA-232
output levels. Coupled with the on-chip
5.5V supplies,
these transmitters deliver true RS-232 levels over a wide
range of single supply system voltages.
All transmitter outputs disable and assume a high impedance
state when the device enters the powerdown mode (see Table
2). These outputs may be driven to
12V when disabled.
The ICL3237 guarantees a 1Mbps data rate (if MBAUD = 1)
for full load conditions (3k
and 250pF), V
CC
3.0V, with
one transmitter operating at full speed. Under more typical
conditions of V
CC
3.3V, C
1-4
= 0.1
F, R
L
= 3k
, and
C
L
= 250pF, one transmitter easily operates at 1.7Mbps.
Transmitter inputs float if left unconnected, and may cause
I
CC
increases. Connect unused inputs to GND for the best
performance.
Receivers
The ICL3237 device contains standard inverting receivers
that three-state only when the EN control line is driven high.
Additionally, it includes a noninverting (monitor) receiver
(denoted by the R
OUTB
label) that is always active,
regardless of the state of any control lines. All the receivers
convert RS-232 signals to CMOS output levels and accept
inputs up to
25V while presenting the required 3k
to 7k
input impedance (see Figure 1) even if the power is off
(V
CC
= 0V). The receivers' Schmitt trigger input stage uses
hysteresis to increase noise immunity and decrease errors
due to slow input signal transitions.
Monitor receivers remain active even during manual
powerdown 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.
Powerdown Functionality
This 3V device requires a nominal supply current of 0.3mA
during normal operation (not in powerdown mode). This is
considerably less than the 5mA to 11mA current required of
5V RS-232 devices. The already low current requirement
drops significantly when the device enters powerdown
mode. In powerdown, supply current drops to 1
A, because
the on-chip charge pump turns off (V+ collapses to V
CC
, V-
collapses to GND), and the transmitter outputs three-state.
This micro-power mode makes the ICL3237 ideal for battery
powered and portable applications.
Software Controlled (Manual) Powerdown
On the ICL3237, the powerdown control is via a simple
shutdown (SHDN) pin. Driving this pin high enables normal
operation, while driving it low forces the IC into it's
powerdown state. Connect SHDN to V
CC
if the powerdown
function isn't needed. Note that all the receiver outputs
remain enabled during shutdown (see Table 2). For the
lowest power consumption during powerdown, the receivers
should also be disabled by driving the EN input high (see
next section, and Figures 2 and 3). The time required to exit
powerdown, and resume transmission is only 100
s.
R
XOUT
GND
V
ROUT
V
CC
5k
R
XIN
-25V
V
RIN
+25V
GND
V
CC
FIGURE 1. INVERTING RECEIVER CONNECTIONS
TABLE 2. POWERDOWN AND ENABLE LOGIC TRUTH TABLE
SHDN INPUT EN INPUT TRANSMITTER OUTPUTS
RECEIVER OUTPUTS
R
OUTB
OUTPUT
MODE OF OPERATION
L
L
High-Z
Active
Active
Manual Powerdown
L
H
High-Z
High-Z
Active
Manual Powerdown w/Rcvr. Disabled
H
L
Active
Active
Active
Normal Operation
H
H
Active
High-Z
Active
Normal Operation w/Rcvr. Disabled
ICL3237
7
Receiver ENABLE Control
This device also features an EN input to control the receiver
outputs. Driving EN high disables all the inverting (standard)
receiver outputs placing them in a high impedance state.
This is useful to eliminate supply current, due to a receiver
output forward biasing the protection diode, when driving the
input of a powered down (V
CC
= GND) peripheral (see
Figure 2). The enable input has no effect on transmitter nor
monitor (R
OUTB
) outputs.
MegaBaud Selection
In normal operating mode (MBAUD = GND), the ICL3237
transmitters guarantee a 250kbps data rate with worst-case
loads of 3k
in parallel with 1000pF. This provides
compatibility with PC-to-PC communication software, such
as LaplinkTM.
For higher speed serial communications, the ICL3237
features MegaBaud operation. In MegaBaud operating
mode (MBAUD = V
CC
), the ICL3237 transmitters guarantee
a 1Mbps data rate with worst-case loads of 3k
in parallel
with 250pF for 3.0V < V
CC
< 4.5V. For 5V
10% operation,
the ICL3237 transmitters guarantee a 1Mbps data rate into
worst-case loads of 3k
in parallel with 1000pF.
Capacitor Selection
The charge pumps require 0.1
F capacitors for 3.3V
operation. For other supply voltages refer to Table 3 for
capacitor values. Do not use values smaller than those listed
in Table 3. Increasing the capacitor values (by a factor of 2)
reduces ripple on the transmitter outputs and slightly
reduces power consumption. C
2
, C
3
, and C
4
can be
increased without increasing C
1
's value, however, do not
increase C
1
without also increasing C
2
, C
3
, and C
4
to
maintain the proper ratios (C
1
to the other capacitors).
When using minimum required capacitor values, make sure
that capacitor values do not degrade excessively with
temperature. If in doubt, use capacitors with a larger nominal
value. The capacitor's equivalent series resistance (ESR)
usually rises at low temperatures and it influences the
amount of ripple on V+ and V-.
Power Supply Decoupling
In most circumstances a 0.1
F bypass capacitor is
adequate. In applications that are particularly sensitive to
power supply noise, decouple V
CC
to ground with a
capacitor of the same value as the charge-pump capacitor C
1
.
Connect the bypass capacitor as close as possible to the IC.
Transmitter Outputs when Exiting
Powerdown
Figure 4 shows the response of two transmitter outputs
when exiting powerdown mode. As they activate, the two
transmitter outputs properly go to opposite RS-232 levels,
with no glitching, ringing, nor undesirable transients. Each
transmitter is loaded with 3k
in parallel with 2500pF. Note
that the transmitters enable only when the magnitude of the
supplies exceed approximately 3V.
High Data Rates
The ICL3237 maintains the RS-232
5V minimum
transmitter output voltages even at high data rates. Figure 5
FIGURE 2. POWER DRAIN THROUGH POWERED DOWN
PERIPHERAL
OLD
V
CC
POWERED
GND
SHDN = GND
V
CC
Rx
Tx
V
CC
CURRENT
V
OUT
=
V
CC
FLOW
RS-232 CHIP
DOWN
UART
FIGURE 3. DISABLED RECEIVERS PREVENT POWER DRAIN
ICL3237
TRANSITION
R
X
T
X
R1
OUTB
R1
OUT
T1
IN
V
CC
V
CC
TO
R1
IN
T1
OUT
V
OUT
=
HI-Z
POWERED
SHDN = GND, EN = V
CC
DETECTOR
DOWN
UART
WAKE-UP
LOGIC
TABLE 3. REQUIRED CAPACITOR VALUES
V
CC
(V)
C
1
(
F)
C
2
, C
3
, C
4
(
F)
3.0 to 3.6
0.22
0.22
3.15 to 3.6
0.1
0.1
4.5 to 5.5
0.047
0.33
3.0 to 5.5
0.22
1.0
ICL3237
Laplink is a registered trademark of Traveling Software.
8
details a transmitter loopback test circuit, and Figure 6
illustrates the standard speed loopback test result for a
single transmitter driving 1000pF and an RS-232 load at
250kbps. Figure 7 shows the megabaud loopback results for
a single transmitter driving 250pF and an RS-232 load at
1Mbps. The static transmitters were also loaded with an
RS-232 receiver.
Interconnection with 3V and 5V Logic
The ICL3237 directly interfaces with most 5V logic families,
including ACT and HCT CMOS. See Table 4 for more
information on possible combinations of interconnections.
FIGURE 5. TRANSMITTER LOOPBACK TEST CIRCUIT
TIME (20
s/DIV.)
T1
T2
2V/DIV.
5V/DIV.
V
CC
= +3.3V
SHDN
FIGURE 4. TRANSMITTER OUTPUTS WHEN EXITING
POWERDOWN
C1 - C4 = 0.1
F
ICL3237
V
CC
C
1
C
2
C
4
C
3
+
+
+
+
C
L
V+
V-
5K
T
IN
R
OUT
C1+
C1-
C2+
C2-
R
IN
T
OUT
+
V
CC
0.1
F
V
CC
EN
SHDN
MBAUD
GND or V
CC
FIGURE 6. LOOPBACK TEST AT 250kbps (C
L
= 1000pF)
FIGURE 7. LOOPBACK TEST AT 1Mbps (C
L
= 250pF)
TABLE 4. LOGIC FAMILY COMPATIBILITY WITH VARIOUS
SUPPLY VOLTAGES
SYSTEM
POWER-SUPPLY
VOLTAGE
(V)
V
CC
SUPPLY
VOLTAGE
(V)
COMPATIBILITY
3.3
3.3
Compatible with all CMOS
families.
5
5
Compatible with all TTL and
CMOS logic families.
5
3.3
Compatible with ACT and HCT
CMOS, and with TTL.
Incompatible with AC, HC, or
CD4000 CMOS.
T1
IN
T1
OUT
R1
OUT
2
s/DIV.
5V/DIV.
V
CC
= +3.3V
C1 - C4 = 0.1
F
MBAUD = GND
T1
IN
T1
OUT
R1
OUT
0.5
s/DIV.
5V/DIV.
V
CC
= +3.3V
C1 - C4 = 0.1
F
MBAUD = V
CC
ICL3237
9
Typical Performance Curves
V
CC
= 3.3V, T
A
= 25
o
C
FIGURE 8. LOW SPEED TRANSMITTER OUTPUT VOLTAGE
vs LOAD CAPACITANCE
FIGURE 9. HIGH SPEED TRANSMITTER OUTPUT VOLTAGE
vs LOAD CAPACITANCE
FIGURE 10. LOW SPEED SLEW RATE vs LOAD CAPACITANCE
FIGURE 11. HIGH SPEED SLEW RATE vs LOAD
CAPACITANCE
FIGURE 12. LOW SPEED SUPPLY CURRENT vs LOAD
CAPACITANCE WHEN TRANSMITTING DATA
FIGURE 13. HIGH SPEED SUPPLY CURRENT vs LOAD
CAPACITANCE WHEN TRANSMITTING DATA
-6
-4
-2
0
2
4
6
1000
2000
3000
4000
5000
0
LOAD CAPACITANCE (pF)
TRAN
SMI
TTER O
U
TPUT VO
LTAG
E
(V)
1 TRANSMITTER AT 250kbps
V
OUT
+
V
OUT
-
OTHER TRANSMITTERS AT 30kbps
MBAUD = GND
-6
-4
-2
0
2
4
6
1000
2000
3000
4000
5000
0
LOAD CAPACITANCE (pF)
TRAN
SMI
TTER O
U
TPUT VO
LTAG
E
(V)
1 TRANSMITTER AT 1Mbps
V
OUT
+
V
OUT
-
OTHER TRANSMITTERS AT 30kbps
MBAUD = V
CC
LOAD CAPACITANCE (pF)
SLE
W
RATE
(V/
s)
0
1000
2000
3000
4000
5000
5
10
15
20
25
+SLEW
-SLEW
MBAUD = GND
-SLEW
LOAD CAPACITANCE (pF)
SLE
W
RATE
(V/
s)
0
1000
2000
3000
4000
5000
10
30
50
-SLEW
+SLEW
70
90
MBAUD = V
CC
0
20
25
30
35
40
55
45
50
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
SUP
P
LY CUR
RE
NT
(mA)
20kbps
250kbps
120kbps
MBAUD = GND
20
30
40
50
80
60
70
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
SUPP
L
Y
CURRENT
(m
A)
120kbps
1Mbps
250kbps
90
MBAUD = V
CC
ICL3237
10
Die Characteristics
SUBSTRATE POTENTIAL (POWERED UP)
GND
TRANSISTOR COUNT
619
PROCESS
Si Gate CMOS
FIGURE 14. SUPPLY CURRENT vs SUPPLY VOLTAGE
Typical Performance Curves
V
CC
= 3.3V, T
A
= 25
o
C (Continued)
SUPP
L
Y
CURRENT
(m
A)
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
0
0.5
1.0
1.5
2.0
SUPPLY VOLTAGE (V)
2.5
3.0
3.5
NO LOAD
ALL OUTPUTS STATIC
ICL3237
11
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation's quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
ICL3237
Shrink Small Outline Plastic Packages (SSOP)
NOTES:
1. Symbols are defined in the "MO Series Symbol List" in Section 2.2
of Publication Number 95.
2. Dimensioning and tolerancing per ANSI Y14.5M-1982.
3. Dimension "D" does not include mold flash, protrusions or gate
burrs. Mold flash, protrusion and gate burrs shall not exceed
0.20mm (0.0078 inch) per side.
4. Dimension "E" does not include interlead flash or protrusions.
Interlead flash and protrusions shall not exceed 0.20mm (0.0078
inch) per side.
5. The chamfer on the body is optional. If it is not present, a visual
index feature must be located within the crosshatched area.
6. "L" is the length of terminal for soldering to a substrate.
7. "N" is the number of terminal positions.
8. Terminal numbers are shown for reference only.
9. Dimension "B" does not include dambar protrusion. Allowable
dambar protrusion shall be 0.13mm (0.005 inch) total in excess of
"B" dimension at maximum material condition.
10. Controlling dimension: MILLIMETER. Converted inch dimensions
are not necessarily exact.
INDEX
AREA
E
D
N
1
2
3
-B-
0.25(0.010)
C A
M
B S
e
-A-
L
B
M
-C-
A1
A
SEATING PLANE
0.10(0.004)
C
H
0.25(0.010)
B
M
M
0.25
0.010
GAUGE
PLANE
A2
M28.209
(JEDEC MO-150-AH ISSUE B)
28 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE
SYMBOL
INCHES
MILLIMETERS
NOTES
MIN
MAX
MIN
MAX
A
-
0.078
-
2.00
-
A1
0.002
-
0.05
-
-
A2
0.065
0.072
1.65
1.85
-
B
0.009
0.014
0.22
0.38
9
C
0.004
0.009
0.09
0.25
-
D
0.390
0.413
9.90
10.50
3
E
0.197
0.220
5.00
5.60
4
e
0.026 BSC
0.65 BSC
-
H
0.292
0.322
7.40
8.20
-
L
0.022
0.037
0.55
0.95
6
N
28
28
7
0
8
0
8
-
Rev. 2 6/05
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