LINER LT1330CJW

LT1330
5V RS232 Transceiver with
3V Logic Interface and One
Receiver Active in Shutdown
U
DESCRIPTIO
FEATURES
■
■
■
■
■
■
■
■
■
■
■
■
■
■
The LT®1330 is a three driver, five receiver RS232 transceiver with low supply current. Designed to interface with
new 3V logic, the LT1330 operates with both a 5V power
supply and a 3V logic power supply. The chip may be shut
down to micropower operation with one receiver remaining active to monitor RS232 inputs such as ring detect
from a modem.
3V Logic Interface
ESD Protection over ±10kV
Uses Small Capacitors: 0.1µF, 0.2µF, 1.0µF
One Low Power Receiver Remains Active While in
Shutdown
Pin Compatible with LT1137A and LT1237
120kBaud Operation for RL = 3k, CL = 2500pF
250kBaud Operation for RL = 3k, CL = 1000pF
CMOS Comparable Low Power: 30mW
Easy PC Layout—Flowthrough Architecture
Rugged Bipolar Design
Outputs Assume a High Impedance State When Off
or Powered Down
Absolutely No Latchup
60µA Supply Current in Shutdown
Available in SO and SSOP Packages
The LT1330 is fully compliant with all EIA RS232 specifications. Additionally, the RS232 line input and output pins
are resilient to multiple ±10kV ESD strikes. This eliminates
the need for costly TransZorbs® on line pins for the RS232
part.
The LT1330 operates to 120kbaud even driving high
capacitive loads. During shutdown, driver and receiver
outputs are at a high impedance state allowing devices to
be paralleled.
UO
APPLICATI
■
■
S
, LTC and LT are registered trademarks of Linear Technology Corporation.
TransZorb is a registered trademark of General Instruments, GSI
Notebook Computers
Palmtop Computers
UO
TYPICAL APPLICATI
Output Waveforms
V+
1.0µF
5V VCC
2 × 0.1µF
DRIVER 1 OUT
RX1 IN
DRIVER 2 OUT
TO
LINE
RX2 IN
RX3 IN
RX4 IN
DRIVER 3 OUT
RX5 IN (LOW-Q)
ON/OFF
3V VL
1
2
28
LT1330
V–
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
2 × 0.1µF
RECEIVER
OUTPUT
VL = 3V
CL = 50pF
0.1µF
DRIVER 1 IN
DRIVER
OUTPUT
RL = 3k
CL = 2500pF
RX1 OUT
DRIVER 2 IN
RX2 OUT
TO LOGIC
R
RX3 OUT
RX4 OUT
DRIVER 3 IN
RX5 OUT (LOW-Q)
GND
DRIVER
DISABLE
INPUT
RING DETECT IN
µCONTROLLER OR
µPROCESSOR
1330 TA02
SHUTDOWN
CONTROL OUT
1330 TA01
1
LT1330
U
U
RATI GS
W
W W
W
AXI U
U
ABSOLUTE
PACKAGE/ORDER I FOR ATIO
(Note 1)
Supply Voltage (VCC) ................................................ 6V
Supply Voltage (VL) .................................................. 6V
V + ........................................................................ 13.2V
V – ...................................................................... –13.2V
Input Voltage
Driver ........................................................... V – to V +
Receiver ................................................ – 30V to 30V
Output Voltage
Driver .................................................... – 30V to 30V
Receiver ...................................... – 0.3V to VL + 0.3V
Short-Circuit Duration
V + ................................................................... 30 sec
V – ................................................................... 30 sec
Driver Output .............................................. Indefinite
Receiver Output .......................................... Indefinite
Operating Temperature Range
LT1330I ............................................. – 40°C to 85°C
LT1330C ................................................. 0°C to 70°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART
NUMBER
TOP VIEW
V+ 1
28 V –
5V VCC 2
27 C2 –
C1+
3
26 C2+
C1–
4
25 DR1 IN
DR1 OUT 5
24 RX1 OUT
RX1 IN 6
23 DR2 IN
DR2 OUT 7
22 RX2 OUT
RX2 IN 8
21 RX3 OUT
RX3 IN 9
20 RX4 OUT
RX4 IN 10
19 DR3 IN
RX5 OUT
18 (LOW-Q)
17 GND
16 DRIVER
DISABLE
15 NC
DR3 OUT 11
RX5 IN 12
(LOW-Q)
ON/OFF 13
3V VL 14
G PACKAGE
28-LEAD PLASTIC SSOP
JW PACKAGE
28-LEAD (WIDE) CERDIP
NW PACKAGE
28-LEAD (WIDE) PDIP
SW PACKAGE
28-LEAD (WIDE) PLASTIC SO
LT1330CG
LT1330CJW
LT1330CNW
LT1330CSW
LT1330IJW
TJMAX = 150°C, θJA = 96°C/ W (G)
TJMAX = 150°C, θJA = 62°C/ W (JW)
TJMAX = 150°C, θJA = 56°C/ W (NW)
TJMAX = 150°C, θJA = 85°C/ W (SW)
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
PARAMETER
Power Supply Generator
V + Output
V – Output
Supply Current (VCC)
(Note 2)
CONDITIONS
MIN
7.9
–7
6
6
0.1
0.06
3.00
0.2
TA = 25°C (Note 3)
●
Supply Current (VL)
Supply Current When OFF (VCC)
Supply Rise Time
Shutdown to Turn-On
ON/OFF Pin Thresholds
ON/OFF Pin Current
DRIVER DISABLE Pin Thresholds
DRIVER DISABLE Pin Current
Oscillator Frequency
2
(Note 4)
Shutdown (Note 5)
Driver Disable
C1 = C2 = 0.2µF,
C + = 1.0µF, C – = 0.1µF
Input Low Level (Device Shutdown)
Input High Level (Device Enabled)
0V ≤ VON/OFF ≤ 5V
Input Low Level (Drivers Enabled)
Input High Level (Drivers Disabled)
0V ≤ VDRIVER DISABLE ≤ 5V
Driver Outputs Loaded RL = 3k
●
●
●
0.8
●
–15
0.8
●
●
●
TYP
1.4
1.4
1.4
1.4
–10
130
MAX
UNITS
12
14
1
0.15
V
V
mA
mA
mA
mA
mA
ms
2.4
80
2.4
500
V
V
µA
V
V
µA
kHz
LT1330
ELECTRICAL CHARACTERISTICS
PARAMETER
CONDITIONS
Any Driver
Output Voltage Swing
Load = 3k to GND
Logic Input Voltage Level
Logic Input Current
Output Short-Circuit Current
Output Leakage Current
Data Rate (Note 8)
Slew Rate
Propagation Delay
Any Receiver
Input Voltage Thresholds
Hysteresis
Input Resistance
Output Leakage Current
Receivers 1, 2, 3, 4
Output Voltage
Output Short-Circuit Current
Propagation Delay
Receiver 5 (LOW Q-Current RX)
Output Voltage
Output Short-Circuit Current
Propagation Delay
(Note 2)
Positive
Negative
Input Low Level (VOUT = High)
Input High Level (VOUT = Low)
0.8V ≤ VIN ≤ 2V
VOUT = 0V
Shutdown VOUT = ±30V (Note 5)
RL = 3k, CL = 2500pF
RL = 3k, CL = 1000pF
RL = 3k, CL = 51pF
RL = 3k, CL = 2500pF
Output Transition tHL High to Low (Note 6)
Output Transition tLH Low to High
●
●
●
●
TYP
5.0
7.5
– 6.3
1.4
1.4
5
17
10
2.0
●
±9
●
4
0.8
●
VIN = ±10V
Shutdown (Note 5) 0 ≤ VOUT ≤ VCC
MAX
0.1
3
●
Output Low, IOUT = – 1.6mA
Output High, IOUT = 160µA (VL = 3V)
Sinking Current, VOUT = VCC
Sourcing Current, VOUT = 0V
Output Transition tHL High to Low (Note 7)
Output Transition tLH Low to High
●
●
Output Low, IOUT = – 500µA
Output High, IOUT = 160µA (VL = 3V)
Sinking Current, VOUT = VCC
Sourcing Current, VOUT = 0V
Output Transition tHL High to Low (Note 7)
Output Transition tLH Low to High
●
●
2.7
– 10
10
2.7
–2
2
UNITS
15
15
0.6
0.5
1.3
1.3
V
V
V
V
µA
mA
µA
kBaud
kBaud
V/µs
V/µs
µs
µs
1.3
1.7
0.4
5
1
2.4
1.0
7
10
V
V
V
kΩ
µA
– 5.0
0.8
20
100
120
250
Input Low Threshold (VOUT = High)
Input High Threshold (VOUT = Low)
The ● denotes specifications which apply over the operating temperature
range (0°C ≤ TA ≤ 70°C for commercial grade, and – 40°C ≤ TA ≤ 85°C for
industrial grade).
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: Testing done at VCC = 5V and VON/OFF = 3V.
Note 3: Supply current is measured as the average over several charge
pump burst cycles. C + = 1.0µF, C – = 0.1µF, C1 = C2 = 0.2µF. All outputs
are open, with all driver inputs tied high.
Note 4: VL supply current is measured with all receiver outputs low.
Note 5: Measurements in shutdown are performed with VON/OFF ≤ 0.1V.
Supply current measurements using driver disable are performed with
VDRIVER DISABLE ≥ 3V.
MIN
0.2
2.9
– 20
20
250
350
0.2
2.9
–4
4
1
1
30
0.4
600
600
0.4
3
3
V
V
mA
mA
ns
ns
V
V
mA
mA
µs
µs
Note 6: For driver delay measurements, RL = 3k and CL = 51pF. Trigger
points are set between the driver’s input logic threshold and the output
transition to the zero crossing (t HL = 1.4V to 0V and tLH = 1.4V to 0V).
Note 7: For receiver delay measurements, CL = 51pF. Trigger points are
set between the receiver’s input logic threshold and the output transition
to standard TTL/CMOS logic threshold (t HL = 1.3V to 2.4V and tLH = 1.7V
to 0.8V).
Note 8: Data rate operation guaranteed by slew rate, short-circuit current
and propagation delay tests.
3
LT1330
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Receiver Input Thresholds
Driver Output Voltage
10
VCC = 5V
OUTPUT HIGH
2.75
VCC = 4.5V
6
4
2
0
–2
–4
OUTPUT LOW
VCC = 4.5V
–6
VCC = 5V
–8
–10
–55 –25
50
25
0
75
TEMPERATURE (°C)
100
80
2.50
2.25
2.00
INPUT HIGH
1.75
1.50
INPUT LOW
1.25
1.00
0.50
–55 –25
50
25
0
75
TEMPERATURE (°C)
1330 G01
40
30
20
100
0
125
0
3.0
125
4
2.5
50
THRESHOLD VOLTAGE (V)
5
75
3
2
1
25
50
25
75
0
TEMPERATURE (°C)
100
0
–55 –25
125
50
25
0
75
TEMPERATURE (°C)
35
SUPPLY CURRENT (mA)
ON THRESHOLD
1.5
1.0
OFF THRESHOLD
0.5
1.0
0
–55 –25
125
50
25
75
0
TEMPERATURE (°C)
100
30
1330 G06
Driver Leakage in Shutdown
100
3DRIVERS LOADED
RL = 3k
25
20
1DRIVER LOADED
RL = 3k
15
10
125
NO LOAD
10
1
VOUT = 30V
VOUT = –30V
5
50
25
75
0
TEMPERATURE (°C)
100
125
1330 G07
4
100
40
2.5
0
–55 –25
1.5
VCC Supply Current
ON/OFF Thresholds
3.0
150
2.0
1330 G05
1330 G04
2.0
125
0.5
LEAKAGE CURRENT ( µA)
0
–55 –25
75
50
100
DATA RATE (kBAUD)
DRIVER DISABLE Threshold
150
100
25
1330 G03
VCC Supply Current in
Driver Disable
SUPPLY CURRENT (mA)
SUPPLY CURRENT (µA)
50
1330 G02
VCC Supply Current in Shutdown
THRESHOLD VOLTAGE (V)
60
10
0.75
125
3DRIVERS ACTIVE
RL = 3k
CL = 2500pF
70
SUPPLY CURRENT (mA)
RL = 3k
THRESHOLD VOLTAGE (V)
DRIVER OUTPUT VOLTAGE (V)
8
Supply Current vs Data Rate
3.00
0
–55 –25
50
25
0
75
TEMPERATURE (°C)
100
125
1330 G08
0.1
–55 –25
50
25
0
75
TEMPERATURE (°C)
100
125
1330 G09
LT1330
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Driver Short-Circuit Current
Receiver Short-Circuit Current
40
25
ISC
SHORT-CIRCUIT CURRENT (mA)
SHORT-CIRCUIT CURRENT (mA)
30
+
20
15
ISC–
10
5
35
RX1 TO RX4
ISC +
30
25
RX1 TO RX4
ISC –
20
15
RX5 ISC +
10
RX5 ISC –
5
0
–55 –25
50
25
75
0
TEMPERATURE (°C)
100
125
0
–55 –25
50
0
75
25
TEMPERATURE (°C)
100
125
1330 G11
1330 G10
Driver Output Waveforms
Receiver Output Waveforms
RX5 OUTPUT
CL = 50pF
DRIVER OUTPUT
RL = 3k
CL = 2500pF
RX1 TO RX4
OUTPUT
CL = 50pF
DRIVER OUTPUT
RL = 3k
INPUT
INPUT
VL = 3V
1330 G12
1330 G13
U
U
U
PI FU CTIO S
VCC: 5V Input Supply Pin. This pin should be decoupled
with a 0.1µF ceramic capacitor close to the package pin.
Insufficient supply bypassing can result in low output
drive levels and erratic charge pump operation.
VL: 3V Logic Supply Pin for all RS232 Receivers. Like VCC,
the VL input should be decoupled with a 0.1µF ceramic
capacitor. This pin may also be connected to 5V.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Operating Mode Control.
A logic low puts the device in the low power shutdown
mode. All three drivers and four receivers (RX1, RX2, RX3,
and RX4) assume a high impedance output state in shutdown. Only receiver RX5 remains active while the transceiver is in shutdown. The transceiver consumes only
60µA of supply current while in shutdown. A logic high
fully enables the transceiver.
DRIVER DISABLE: This pin provides an alternate control
for the charge pump and RS232 drivers. A logic high on
this pin shuts down the charge pump and places all driver
outputs in a high impedance state. All five receivers remain
active under these conditions. Floating the driver disable
pin or driving it to a logic low level fully enables the
transceiver. A logic low on the ON/OFF pin supersedes the
state of the DRIVER DISABLE pin. Supply current drops to
3mA when in driver disable mode.
V +: Positive Supply Output. V + ≈ 2VCC – 1.5V. This pin
requires an external charge storage capacitor, C ≥ 1.0µF,
tied to ground or 5V. Larger value capacitors may be used
5
LT1330
U
U
U
PI FU CTIO S
to reduce supply ripple. The ratio of the capacitors on V +
and V – should be greater than 5 to 1.
V –: Negative Supply Output. V – ≈ –(2VCC – 2.5V). This pin
requires an external charge storage capacitor, C ≥ 0.1µF.
See the Applications Information section for guidance in
choosing filter capacitors for V + and V –.
C1+, C1–, C2+, C2 –: Commutating Capacitor Inputs require two external capacitors, C ≥ 0.2µF: one from C1+ to
C1–, and another from C2 + to C2 –. The capacitor’s effective series resistance should be less than 2Ω. For C ≥ 1µF,
low ESR tantalum capacitors work well, although ceramic
capacitors may be used with a minimal reduction in charge
pump compliance.
DRIVER IN: RS232 Driver Input Pins. These inputs are
TTL/CMOS compatible. Unused inputs should be connected to VCC.
DRIVER OUT: Driver Outputs at RS232 Voltage Levels.
Driver output swing meets RS232 levels for loads up to 3k.
Slew rates are controlled for lightly loaded lines. Output
current capability is sufficient for load conditions up to
2500pF. Outputs are in a high impedance state when in
shutdown mode, VCC = 0V, or when the DRIVER DISABLE
pin is active. Outputs are fully short-circuit protected from
V – + 30V to V + – 30V. Applying higher voltages will not
damage the device if the overdrive is moderately current
limited. Short circuits on one output can load the power
supply generator and may disrupt the signal levels of the
other outputs. The driver outputs are protected against
ESD to ±10kV for human body model discharges.
RX IN: Receiver Inputs. These pins accept RS232 level
signals (±30V) into a protected 5k terminating resistor.
The receiver inputs are protected against ESD to ±10kV for
human body model discharges. Each receiver provides
0.4V of hysteresis for noise immunity. Open receiver
inputs assume a logic low state.
RX OUT: Receiver Outputs with TTL/CMOS Voltage Levels. Outputs are in a high impedance state when in shutdown mode to allow data line sharing. Outputs, including
LOW-Q RX OUT, are fully short-circuit protected to ground
or VCC with the power on, off, or in shutdown mode.
LOW Q-CURRENT RX IN: Low Power Receiver Input. This
special receiver remains active when the part is in shutdown mode, consuming typically 60µA. This receiver has
the same 5k input impedance and ±10kV ESD protection
characteristics as the other receivers.
LOW Q-CURRENT RX OUT: Low Power Receiver Output.
This pin produces the same TTL/CMOS output voltage
levels as receivers RX1, RX2, RX3, and RX4 with slightly
decreased speed and short-circuit current. Data rates to
120kbaud are supported by this receiver.
U
ESD PROTECTIO
The RS232 line inputs of the LT1330 have on-chip protection from ESD transients up to ±10kV. The protection
structures act to divert the static discharge safely to
system ground. In order for the ESD protection to function
effectively, the power supply and ground pins of the
LT1330 must be connected to ground through low impedances. The power supply decoupling capacitors and charge
pump storage capacitors provide this low impedance in
normal application of the circuit. The only constraint is that
low ESR capacitors must be used for bypassing and
charge storage. ESD testing must be done with pins VCC,
VL, V +, V –, and GND shorted to ground or connected with
low ESR capacitors.
6
ESD Test Circuit
1
V+
5V VCC 2
1µF
0.1µF
0.2µF
DRIVER 1 OUT
RX1 IN
DRIVER 2 OUT
RS232
LINE PINS
PROTECTED
TO ±10kV
RX2 IN
RX3 IN
RX4 IN
DRIVER 3 OUT
RX5 IN (LOW-Q)
ON/OFF
3V VL
28
LT1330
V–
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
0.1µF
0.2µF
DRIVER 1 IN
RX1 OUT
DRIVER 2 IN
RX2 OUT
RX3 OUT
RX4 OUT
DRIVER 3 IN
RX5 OUT (LOW-Q)
GND
DRIVER DISABLE
1330 TC01
0.1µF
LT1330
W
U
U
UO
APPLICATI
S I FOR ATIO
Storage Capacitor Selection
The V + and V – storage capacitors must be chosen carefully to insure low ripple and stable operation. The LT1330
charge pump operates in a power efficient Burst ModeTM
operation. When storage capacitor voltage drops below a
preset threshold, the oscillator is gated on until V+ and V –
are boosted up to levels exceeding a second threshold.
The oscillator then turns off, and current is supplied from
the V+ and V – storage capacitors.
The V – potential is monitored to control charge pump
operation. It is therefore important to insure lower V +
ripple than V – ripple, or erratic operation of the charge
pump will result. Proper operation is insured in most
applications by choosing the V+ filter capacitor to be at
least 5 times the V – filter capacitor value. If V + is more
heavily loaded than V –, a larger ratio may be needed.
The V – filter capacitor should be selected to obtain low
ripple when the drivers are loaded, forcing the charge
pump into continuous mode. A minimum value 0.1µF is
suggested.
U
PACKAGE DESCRIPTIO
Do not attempt to reduce V – ripple when the charge pump
is in discontinuous Burst Mode operation. The ripple in
this mode is determined by internal comparator thresholds. Larger storage capacitor values increase the burst
period, and do not reduce ripple amplitude.
Power Saving Operational Modes
The LT1330 has both shutdown and driver disable operating modes. These operating modes can optimize power
consumption based upon applications needs.
The On/Off shutdown control turns off all circuitry except
for Low-Q RX5. When RX5 detects a signal, this information can be used to wake up the system for full operation.
If more than one line must be monitored, the driver disable
mode provides a power efficient operating option. The
driver disable mode turns off the charge pump and RS232
drivers, but keeps all five receivers active. Power consumption in driver disable mode is 3mA from VCC.
Burst Mode is a trademark of Linear Technology Corporation
Dimensions in inches (millimeters) unless otherwise noted.
G Package
28-Lead Plastic SSOP (0.209)
(LTC DWG # 05-08-1640)
0.397 – 0.407*
(10.07 – 10.33)
0.205 – 0.212**
(5.20 – 5.38)
0.068 – 0.078
(1.73 – 1.99)
28 27 26 25 24 23 22 21 20 19 18 17 16 15
0° – 8°
0.0256
(0.65)
BSC 0.010 – 0.015
(0.25 – 0.38)
0.005 – 0.009 0.022 – 0.037
(0.13 – 0.22) (0.55 – 0.95)
0.301 – 0.311
(7.65 – 7.90)
0.002 – 0.008
(0.05 – 0.21)
*DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
1 2 3 4 5 6 7 8 9 10 11 12 13 14
G28 SSOP 0694
JW Package
28-Lead CERDIP (Wide 0.600, Hermetic)
(LTC DWG # 05-08-1120)
0.015 – 0.075
(0.381 – 1.904)
0° – 15°
(
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
0.025
(0.635)
RAD TYP
0.008 – 0.018
(0.203 – 0.457)
+0.025
0.685 –0.060
+0.635
17.40
–1.524
1.490
(37.85)
MAX
0.225
(5.715)
MAX
0.600 TYP
(15.240 TYP)
0.510 – 0.620
(12.95 – 15.75)
MAX
)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP
OR TIN PLATE LEADS
0.125
(3.175)
MIN
0.045 – 0.068
(1.143 – 1.727)
0.005
(0.127)
MIN
0.100 ± 0.010
(2.540 ± 0.254)
0.014 – 0.026
(0.360 – 0.660)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
J28 1197
7
LT1330
U
TYPICAL APPLICATION
Typical Mouse Driving Application
1.0µF
MOUSE
V+
1
5V VCC
2
2 × 0.1µF
(1)
OPTICS
(5)
26
25 DRIVER 1 IN
24 RX1 OUT
DCD
RX1 IN
6
23 DRIVER 2 IN
DSR
DRIVER 2 OUT
7
22 RX2 OUT
RX
RX2 IN
8
21 RX3 OUT
RTS
RX3 IN
9
20 RX4 OUT
DRIVER 3 OUT 11
DTR
RX5 IN (LOW-Q) 12
LOGIC “0”
LOGIC “0”
MOUSE DATA
19 DRIVER 3 IN
RX4 IN 10
CTS
LOGIC “1”
18 RX5 OUT (LOW-Q)
17 GND
16 DRIVER DISABLE
ON/OFF 13
15
3V VL 14
DB9
U
PACKAGE DESCRIPTIO
0.1µF
2 × 0.1µF
5
RI
(9)
3
4
TX
V–
27
DRIVER 1 OUT
V+
LOGIC
V–
28
LT1330
1330 TA03
Dimensions in inches (millimeters) unless otherwise noted.
NW Package
28-Lead PDIP (Wide 0.600)
(LTC DWG # 05-08-1520)
0.150 ± 0.005
(3.810 ± 0.127)
0.600 – 0.625
(15.240 – 15.875)
0.070
(1.778)
TYP
0.045 – 0.065
(1.143 – 1.651)
1.455*
(36.957)
MAX
28
27
26
25
24
23
22
21
20
19
18
17
16
1
2
3
4
5
6
7
8
9
10
11
12
13
0.015
(0.381)
MIN
0.009 – 0.015
(0.229 – 0.381)
0.505 – 0.560*
(12.827 – 14.224)
+0.035
0.625 –0.015
+0.889
15.87
–0.381
(
15
0.125
(3.175)
MIN
)
0.018 ± 0.003
(0.457 ± 0.076)
0.035 – 0.080
(0.889 – 2.032)
0.100 ± 0.010
(2.540 ± 0.254)
14
N28 1197
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
SW Package
28-Lead Plastic Small Outline (Wide 0.300)
(LTC DWG # 05-08-1620)
0.291 – 0.299**
(7.391 – 7.595)
0.010 – 0.029 × 45° 0.093 – 0.104
(2.362 – 2.642)
(0.254 – 0.737)
0.037 – 0.045
(0.940 – 1.143)
0.697 – 0.712*
(17.70 – 18.08)
28 27 26 25 24 23 22 21 20 19 18 17 16 15
0° – 8° TYP
0.009 – 0.013
(0.229 – 0.330)
0.050
(1.270)
TYP 0.014 – 0.019
(0.356 – 0.482)
TYP
NOTE 1
0.016 – 0.050
(0.406 – 1.270)
NOTE:
1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS.
THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS
0.394 – 0.419
(10.007 – 10.643)
NOTE 1
0.004 – 0.012
(0.102 – 0.305)
1
2
3
4
5
6
7
8
9 10 11 12 13 14
S28 (WIDE) 0996
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
RELATED PARTS
PART NUMBER
LT1137A
LT1237
LT1780/LT1781
8
DESCRIPTION
5V RS232 Transceiver
RS232 Transceiver
2 Driver/2 Receiver RS232 Transceivers
Linear Technology Corporation
COMMENTS
IEC-1000-4-2 ESD Compliant
1 Receiver Active in Shutdown
IEC-1000-4-2 ESD Compliant
1330fa LT/TP 1098 2K REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1992