1
FN8037.4
ISL4241E, ISL4243E
QFN Packaged, 15kV ESD Protected,
+2.7V to +5.5V, 10Nanoamp, 250kbps,
RS-232 Transmitters/Receivers
The Intersil ISL424XE devices are 2.7V 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. Additionally,
they provide
15kV ESD protection (IEC61000-4-2 Air Gap
and Human Body Model) on transmitter outputs and receiver
inputs (RS-232 pins). Targeted applications are 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 and automatic powerdown functions, reduce the
standby supply current to a 10nA trickle. Tiny 5mm x 5mm
Quad Flat No-Lead (QFN) packaging and the use of small,
low value capacitors ensure board space savings as well.
Data rates greater than 250kbps are guaranteed at worst
case load conditions.
The ISL424XE are 3 driver, 5 receiver devices that, coupled
with the 5x5 QFN package, provide the industry's smallest,
lowest power complete serial port suitable for PDAs, and
laptop or notebook computers. The 5x5 QFN requires 60%
less board area than a 28 lead TSSOP, and is nearly 20%
thinner. The devices also include a noninverting always-
active receiver for "wake-up" capability.
The ISL4243E features an automatic powerdown function
that powers down the on-chip power-supply and driver
circuits. This occurs when an attached peripheral device is
shut off or the RS-232 cable is removed, conserving system
power automatically without changes to the hardware or
operating system. It powers up again when a valid RS-232
voltage is applied to any receiver input.
Table 1 summarizes the features of the ISL424XE, while
Application Note AN9863 summarizes the features of each
device comprising the 3V RS-232 family.
Features
Pb-free Available as an Option
Parameters Fully Specified for 10% Tolerance Supplies
and Full Industrial Temp Range
Available in Small QFN (5mm x 5mm) Package which is
60% Smaller than a 28 Lead TSSOP
ESD Protection for RS-232 I/O Pins to
15kV (IEC61000)
Meets EIA/TIA-232 and V.28/V.24 Specifications at 3V
RS-232 Compatible with V
CC
= 2.7V
On-Chip Voltage Converters Require Only Four External
0.1
F Capacitors
Manual and Automatic Powerdown Features
Receiver Hysteresis For Improved Noise Immunity
Guaranteed Minimum Data Rate . . . . . . . . . . . . . 250kbps
Wide Power Supply Range. . . . . . . Single +2.7V to +5.5V
Low Supply Current in Powerdown State . . . . . . . . . .10nA
Applications
Any Space Constrained System Requiring RS-232 Ports
- Battery Powered, Hand-Held, and Portable Equipment
- Laptop Computers, Notebooks
- PDAs and Palmtops, Data Cables
- Cellular/Mobile Phones, Digital Cameras, GPS
Receivers
Related Literature
Technical Brief TB363 "Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
"Technical Brief TB379 "Thermal Characterization of
Packages for ICs"
Technical Brief TB389 "PCB Land Pattern Design and
Surface Mount Guidelines for QFN Packages"
TABLE 1. SUMMARY OF FEATURES
PART
NUMBER
NO. OF
Tx.
NO. OF
Rx.
QFN PKG.
AVAILABLE?
NO. OF
MONITOR Rx.
(R
OUTB
)
DATA
RATE
(kbps)
Rx. ENABLE
FUNCTION?
READY
OUTPUT?
MANUAL
POWER-
DOWN?
AUTOMATIC
POWERDOWN
FUNCTION?
ISL4241E
3
5
YES
2
250
YES
NO
YES
NO
ISL4243E
3
5
YES
1
250
NO
NO
YES
YES
Data Sheet
May 2004
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2004. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
2
Ordering Information
PART NO.
TEMP. RANGE
(C)
PACKAGE
PKG. DWG. #
ISL4241EIR
-40 to 85
32 Ld QFN
L32.5x5
ISL4241EIRZ
(See Note)
-40 to 85
32 Ld QFN
(Pb-free)
L32.5x5
ISL4241EIR-T
-40 to 85
Tape & Reel
L32.5x5
ISL4241EIRZ-T
(See Note)
-40 to 85
Tape & Reel
(Pb-free)
L32.5x5
ISL4243EIR
-40 to 85
32 Ld QFN
L32.5x5
ISL4243EIRZ
(See Note)
-40 to 85
32 Ld QFN
(Pb-free)
L32.5x5
ISL4243EIR-T
-40 to 85
Tape & Reel
L32.5x5
ISL4243EIRZ-T
(See Note)
-40 to 85
Tape & Reel
(Pb-free)
L32.5x5
NOTE: Intersil Pb-free products employ special Pb-free material
sets; molding compounds/die attach materials and 100% matte tin
plate termination finish, which is 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-020B.
Pinouts
ISL4241E (QFN)
TOP VIEW
ISL4243E (QFN)
TOP VIEW
R1
IN
R2
IN
R3
IN
R4
IN
R5
IN
T1
OUT
T2
OUT
C1-
EN
SHDN
R1
OUTB
R2
OUTB
R1
OUT
R2
OUT
T3
OUT
T3
IN
T2
IN
T1
IN
R5
OU
T
R3
OU
T
R4
OU
T
V-
C2-
C2+
C1+
V+
GND
V
CC
NC
7
11
12
13
14
15
9
10
6
1
2
3
4
5
8
16
18
19
24
23
22
21
20
17
27
28
29
30
31
25
26
32
NC
NC
NC
R1
IN
R2
IN
R3
IN
R4
IN
R5
IN
T1
OUT
T2
OUT
C1-
FORCEON
FORCEOFF
INVALID
R2
OUTB
R1
OUT
R2
OUT
T3
OUT
T3
IN
T2
IN
T1
IN
R5
OUT
R3
OUT
R4
OUT
V-
C2-
C2+
C1+
V+
GND
V
CC
NC
7
11
12
13
14
15
9
10
6
1
2
3
4
5
8
16
18
19
24
23
22
21
20
17
27
28
29
30
31
25
26
32
NC
NC
NC
ISL4241E, ISL4243E
3
Pin Descriptions
PIN
FUNCTION
V
CC
System power supply input (2.7V 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
15kV ESD Protected
,
RS-232 level (nominally
5.5V) transmitter outputs.
R
IN
15kV ESD Protected
,
RS-232 compatible receiver inputs.
R
OUT
TTL/CMOS level receiver outputs.
R
OUTB
TTL/CMOS level, noninverting, always enabled receiver outputs.
INVALID
Active low output that indicates if no valid RS-232 levels are present on any receiver input.
FORCEOFF Active low to shut down transmitters and on-chip power supply. This overrides any automatic circuitry and FORCEON (see Table 2).
FORCEON
Active high input to override automatic powerdown circuitry thereby keeping transmitters active. (FORCEOFF must be high).
EN
Active low receiver enable control.
SHDN
Active low input to shut down transmitters and on-board power supply, to place device in low power mode.
NC
No Connection
ISL4241E, ISL4243E
4
Typical Operating Circuits
ISL4241E
ISL4243E
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
12
11
6
7
10
8
28
23
27
31
V+
V-
C1+
C1-
C2+
C2-
+
0.1
F
29
30
R1
OUT
R1
IN
1
5k
R2
OUT
R2
IN
2
17
5k
R3
OUT
R3
IN
3
15
5k
R4
OUT
R4
IN
4
14
5k
R5
OUT
R5
IN
R
5
5
13
5k
18
R2
OUTB
C
1
C
2
+ C
3
C
4
EN
SHDN
22
GND
21
+3.3V
+
0.1
F
19
24
V
CC
TTL/CMOS
LOGIC
RS-232
LEVELS
RS-232
LEVELS
R1
OUTB
20
R
1
R
2
R
3
R
4
LEVELS
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
12
11
6
7
10
8
28
23
27
31
V+
V-
C1+
C1-
C2+
C2-
+
0.1
F
29
30
R1
OUT
R1
IN
1
5k
R2
OUT
R2
IN
2
17
5k
R3
OUT
R3
IN
3
15
5k
R4
OUT
R4
IN
4
14
5k
R5
OUT
R5
IN
R
5
5
13
5k
18
R2
OUTB
C
1
C
2
+
C
3
C
4
FORCEON
FORCEOFF
22
GND
21
+3.3V
+
0.1
F
19
24
V
CC
TTL/CMOS
LOGIC
RS-232
LEVELS
RS-232
LEVELS
R
1
R
2
R
3
R
4
20
INVALID
TO POWER
CONTROL
LEVELS
LOGIC
ISL4241E, ISL4243E
5
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
, FORCEOFF, FORCEON, EN, SHDN . . . . . . . . . -0.3V to 6V
R
IN
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25V
Output Voltages
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.2V
R
OUT
, INVALID. . . . . . . . . . . . . . . . . . . . . . . . -0.3V to V
CC
+0.3V
Short Circuit Duration
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . See Specification Table
Thermal Resistance (Typical, Note 1)
JA
(C/W)
32 Ld QFN Package. . . . . . . . . . . . . . . . . . . . . . . . .
32
Maximum Junction Temperature (Plastic Package) . . . . . . . 150C
Maximum Storage Temperature Range . . . . . . . . . . . -65C to 150C
Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . 300C
Operating Conditions
Temperature Range
ISL424XEIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40C to 85C
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:
1.
JA
is measured in free air with the component mounted on a high effective thermal conductivity test board with "direct attach" features. See
Tech Brief TB379, and Tech Brief TB389.
Electrical Specifications
Test Conditions: V
CC
= 3V to 5.5V, C
1
- C
4
= 0.1
F; Unless Otherwise Specified.
Typicals are at T
A
= 25C
PARAMETER
TEST CONDITIONS
TEMP
(C)
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS
Operating Voltage Range
Full
2.7
-
5.5
V
Supply Current, Automatic
Powerdown
All R
IN
Open, FORCEON = GND, FORCEOFF = V
CC
(ISL4243E Only)
25
-
3
300
nA
Full
-
50
300
nA
Supply Current, Powerdown
All R
IN
Open, FORCEOFF = SHDN = GND
25
-
3
300
nA
Full
-
50
300
nA
Supply Current,
Automatic Powerdown Disabled
All Outputs Unloaded,
FORCEON = FORCEOFF = SHDN = V
CC
, V
CC
= 3.0V
25
-
0.3
1.0
mA
Full
-
0.3
1.5
mA
LOGIC AND TRANSMITTER INPUTS AND RECEIVER OUTPUTS
Input Logic Threshold Low
T
IN
, FORCEON, FORCEOFF, EN, SHDN
Full
-
-
0.8
V
Input Logic Threshold High
T
IN
, FORCEON, FORCEOFF, EN, SHDN, V
CC
= 3.6V
Full
2.0
-
-
V
Input Leakage Current
T
IN
, FORCEON, FORCEOFF, EN, SHDN
Full
-
0.01
1.0
A
Output Leakage Current
FORCEOFF = GND (ISL4243E) or EN = V
CC
(ISL4241E)
Full
-
0.05
10
A
Transmitter Input Hysteresis
25
-
0.5
-
V
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
AUTOMATIC POWERDOWN (ISL4243E Only, FORCEON = GND, FORCEOFF = V
CC
)
Receiver Input Thresholds to
Enable Transmitters
ISL4243E Powers Up (See Figure 7)
Full
-2.7
-
2.7
V
Receiver Input Thresholds to
Disable Transmitters
ISL4243E Powers Down (See Figure 7)
Full
-0.3
-
0.3
V
INVALID Output Voltage Low
I
OUT
= 1.6mA
Full
-
-
0.4
V
INVALID Output Voltage High
I
OUT
= -1.0mA
Full
V
CC
-0.6
-
-
V
Receiver Threshold to Transmitters
Enabled Delay (t
WU
)
Full
-
20
100
s
ISL4241E, ISL4243E
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