LTC485
1
485fm
For more information www.linear.com/LTC485
TYPICAL APPLICATION
DESCRIPTION
Low Power RS485
Interface Transceiver
The LT C
®
485 is a low power differential bus/line trans-
ceiver designed for multipoint data transmission standard
RS485 applications with extended common mode range
(12V to –7V). It also meets the requirements of RS422.
The CMOS design offers significant power savings over
its bipolar counterpart without sacrificing ruggedness
against overload or ESD damage.
The driver and receiver feature three-state outputs, with
the driver outputs maintaining high impedance over the
entire common mode range. Excessive power dissipa-
tion caused by bus contention or faults is prevented by a
thermal shutdown circuit which forces the driver outputs
into a high impedance state.
The receiver has a fail-safe feature which guarantees a
high output state when the inputs are left open.
The LTC485 is fully specified over the commercial and
extended industrial temperature range.
Driver Outputs
FEATURES
APPLICATIONS
n Low Power: ICC = 300μA Typ
n Designed for RS485 Interface Applications
n Single 5V Supply
n –7V to 12V Bus Common Mode Range Permits
±7V Ground Difference Between Devices on the Bus
n Thermal Shutdown Protection
n Power-Up/Down Glitch-Free Driver Outputs
Permit Live Insertion or Removal of Transceiver
n Driver Maintains High Impedance in Three-State
or with the Power Off
n Combined Impedance of a Driver Output and
Receiver Allows Up to 32 Transceivers on the Bus
n 70mV Typical Input Hysteresis
n 30ns Typical Driver Propagation Delays
with 5ns Skew for Up to 2.5MB Operation
n Pin Compatible with ±60V Protected LTC2862
n Low Power RS485/RS422 Transceiver
n Level Translator
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
VCC1
GND1
R
RO1
RE1
DE1
DI1 D
VCC2
GND2
R
RO2
RE2
DE2
DI2 D
Rt
Rt
485 TA01a
485 TA01b
A
B
LTC485
2
485fm
For more information www.linear.com/LTC485
PIN CONFIGURATIONABSOLUTE MAXIMUM RATINGS
Supply Voltage .......................................................... 12V
Control Input Voltages .................... –0.5V to VCC + 0.5V
Driver Input Voltage ........................ –0.5V to VCC + 0.5V
Driver Output Voltage.............................................. ±14V
Receiver Input Voltage ............................................ ±14V
Receiver Output Voltages ............... –0.5V to VCC + 0.5V
Operating Temperature Range
LTC485I ........................................ –40°C ≤ TA ≤ 85°C
LTC485C ............................................0°C ≤ TA ≤ 70°C
LTC485M (OBSOLETE) ................–55°C ≤ TA ≤ 125°C
Lead Temperature (Soldering, 10 sec) ...................300°C
Storage Temperature Range .................. –65°C to 150°C
(Note 1)
N8 PACKAGE
8-LEAD PLASTIC DIP
1
2
3
4
8
7
6
5
TOP VIEW
VCC
B
A
GND
S8 PACKAGE
8-LEAD PLASTIC SOIC
R
D
RO
RE
DE
DI
J8 PACKAGE
8-LEAD CERAMIC DIP
TJMAX = 125°C, θJA = 100°C/W (N)
TJMAX = 150°C, θJA = 150°C/W (S)
TJMAX = 155°C, θJA = 100°C/W (J)
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC485CN8#PBF NA LTC485CN8 8-Lead Plastic DIP 0°C to 70°C
LTC485CS8#PBF LTC485CS8#TRPBF 485 8-Lead Plastic SOIC 0°C to 70°C
LTC485IN8#PBF NA LTC485IN8 8-Lead Plastic DIP –40°C to 85°C
LTC485IS8#PBF LTC485IS8#TRPBF 485I 8-Lead Plastic SOIC –40°C to 85°C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC485CN8 NA LTC485CN8 8-Lead Plastic DIP 0°C to 70°C
LTC485CS8 LTC485CS8#TR 485 8-Lead Plastic SOIC 0°C to 70°C
LTC485IN8 NA LTC485IN8 8-Lead Plastic DIP –40°C to 85°C
LTC485IS8 LTC485IS8#TR 485I 8-Lead Plastic SOIC –40°C to 85°C
OBSOLETE PACKAGE
LTC485MJ8 NA LTC485MJ8 8-Lead Ceramic DIP –55°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/. Some packages are available in 500 unit reels through
designated sales channels with #TRMPBF suffix.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VOD1 Differential Driver Output Voltage (Unloaded) IO = 0 l5 V
VOD2 Differential Driver Output Voltage (with Load) R = 50Ω (RS422)
R = 27Ω (RS485), Figure 1
l
l
2
1.5
5
V
V
ΔVOD Change in Magnitude of Driver Differential
Output Voltage for Complementary States
R = 27Ω or R = 50Ω, Figure 1 l0.2 V
VOC Driver Common Mode Output Voltage R = 27Ω or R = 50Ω, Figure 1 l 3 V
Δ|VOC| Change in Magnitude of Driver Common Mode
Output Voltage for Complementary States
R = 27Ω or R = 50Ω, Figure 1 l0.2 V
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 5V ±5%, unless otherwise noted. (Notes 2 and 3)
http://www.linear.com/product/LTC485#orderinfo
OBSOLETE PACKAGE
LTC485
3
485fm
For more information www.linear.com/LTC485
ELECTRICAL CHARACTERISTICS
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to device ground unless
otherwise specified.
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 5V ±5%, unless otherwise noted. (Notes 2 and 3)
SWITCHING CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 5V ±5%, unless otherwise noted. (Notes 2 and 3)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
ICC Supply Current No Load, Pins 2, 3, 4 = 0V or 5V Outputs Enabled
Outputs Disabled
l
l
500
300
900
500
μA
μA
IOSD1 Driver Short-Circuit Current, VOUT = HIGH VO = – 7V l 35 100 250 mA
IOSD2 Driver Short-Circuit Current, VOUT = LOW VO = 10V l 35 100 250 mA
IOSR Receiver Short-Circuit Current 0V ≤ VO ≤ VCC l 7 85 mA
tPLH Driver Input to Output RDIFF = 54Ω, CL1 = CL2 = 100pF,
(Figures 3 and 5)
l 10 30 50 ns
tPHL Driver Input to Output l 10 30 50 ns
tSKEW Driver Output to Output l 5 10 ns
tr, tf Driver Rise or Fall Time l3 15 25 ns
tZH Driver Enable to Output High CL = 100pF (Figures 4 and 6) S2 Closed l40 70 ns
tZL Driver Enable to Output Low CL = 100pF (Figures 4 and 6) S1 Closed l40 70 ns
tLZ Driver Disable Time from Low CL = 15pF (Figures 4 and 6) S1 Closed l 40 70 ns
tHZ Driver Disable Time from High CL = 15pF (Figures 4 and 6) S2 Closed l40 70 ns
tPLH Receiver Input to Output RDIFF = 54Ω, CL1 = CL2 = 100pF,
(Figures 3 and 7)
l30 90 200 ns
tPHL l30 90 200 ns
tSKD |tPLH – tPHL| Differential Receiver Skew l 13 ns
tZL Receiver Enable to Output Low CRL = 15pF (Figures 2 and 8) S1 Closed l 20 50 ns
tZH Receiver Enable to Output High CRL = 15pF (Figures 2 and 8) S2 Closed l20 50 ns
tLZ Receiver Disable from Low CRL = 15pF (Figures 2 and 8) S1 Closed l20 50 ns
tHZ Receiver Disable from High CRL = 15pF (Figures 2 and 8) S2 Closed l20 50 ns
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIH Input High Voltage DE, DI, RE l 2 V
VIL Input Low Voltage DE, DI, RE l 0.8 V
IIN1 Input Current DE, DI, RE l ±2 μA
IIN2 Input Current (A, B) DE = 0, VCC = 0V or 5.25V VIN = 12V
C-, I-Grade VIN = –7V
l
l
1
–0.8
mA
mA
M-Grade VIN = 12V
VIN = –7V
l
l
2
–1.6
mA
mA
VTH Differential Input Threshold Voltage for Receiver –7V ≤ VCM ≤ 12V l –0.2 0.2 V
ΔVTH Receiver Input Hysteresis VCM = 0V l 70 mV
VOH Receiver Output High Voltage IO = –4mA, VID = 200mV l 3.5 V
VOL Receiver Output Low Voltage IO = 4mA, VID = –200mV l0.4 V
IOZR Three-State (High Impedance) Output Current
at Receiver
VCC = Max, 0.4V ≤ VO ≤ 2.4V l ±1 μA
RIN Receiver Input Resistance –7V ≤ VCM ≤ 12V (C-, I-Grade)
(M-Grade)
l
l
12
6
kΩ
kΩ
Note 3: All typicals are given for VCC = 5V and TA = 25°C.
Note 4: The LTC485 is guaranteed by design to be functional over a supply
voltage range of 5V ±10%. Data sheet parameters are guaranteed over the
tested supply voltage range of 5V ±5%.
LTC485
4
485fm
For more information www.linear.com/LTC485
TYPICAL PERFORMANCE CHARACTERISTICS
Receiver Output Low Voltage
vs Temperature
Driver Differential Output Voltage
vs Output Current
Driver Differential Output Voltage
vs Temperature
Driver Output Low Voltage
vs Output Current
Driver Output High Voltage
vs Output Current
TTL Input Threshold
vs Temperature
Receiver Output Low Voltage
vs Output Current
Receiver Output High Voltage
vs Output Current
Receiver Output High Voltage
vs Temperature
OUTPUT VOLTAGE (V)
0
0
OUTPUT CURRENT (mA)
4
12
16
20
1.0
36
485 G01
8
0.5 2.0
24
28
32
1.5
TA = 25°C
OUTPUT VOLTAGE (V)
5
0
OUTPUT CURRENT (mA)
–2
–6
–8
–10
3
–18
485 G02
–4
4
–12
–14
–16
2
TA = 25°C
TEMPERATURE (°C)
–50
3.0
OUTPUT VOLTAGE (V)
3.2
3.6
3.8
4.0
75
4.8
485 G03
3.4
0 125
4.2
4.4
4.6
–25 25 50 100
I = 8mA
TEMPERATURE (°C)
–50
0
OUTPUT VOLTAGE (V)
0.1
0.3
0.4
0.5
75
0.9
485 G04
0.2
0 125
0.6
0.7
0.8
–25 25 50 100
I = 8mA
OUTPUT VOLTAGE (V)
0
0
OUTPUT CURRENT (mA)
8
24
32
40
2
72
485 G05
16
1 3
48
56
64
4
TA = 25°C
TEMPERATURE (°C)
–50
1.5
DIFFERENTIAL VOLTAGE (V)
1.6
1.8
1.9
2.0
75
2.4
485 G06
1.7
0 125
2.1
2.2
2.3
–25 25 50 100
RI = 54Ω
OUTPUT VOLTAGE (V)
0
0
OUTPUT CURRENT (mA)
10
30
40
50
2
90
20
1 3
60
70
80
4
TA = 25°C
OUTPUT VOLTAGE (V)
0
0
OUTPUT CURRENT (mA)
–12
–36
–48
–60
2
–108
485 G08
–24
1 3
–72
–84
–96
4
TA = 25°C
TEMPERATURE (°C)
–50
1.55
INPUT THRESHOLD VOLTAGE (V)
1.56
1.58
1.59
1.60
75
1.64
485 G09
1.57
0 125
1.61
1.62
1.63
–25 25 50 100
LTC485
5
485fm
For more information www.linear.com/LTC485
TYPICAL PERFORMANCE CHARACTERISTICS
Receiver |tPLH – tPHL|
vs Temperature Driver Skew vs Temperature Supply Current vs Temperature
TEMPERATURE (°C)
–50
3.0
TIME (ns)
3.5
4.5
5.0
5.5
75
7.5
485 G10
4.0
0 125
6.0
6.5
7.0
–25 25 50 100
TEMPERATURE (°C)
–50
0
TIME (ns)
0.6
1.8
2.4
3.0
75
5.4
485 G11
1.2
0 125
3.6
4.2
4.8
–25 25 50 100
TEMPERATURE (°C)
–50
100
SUPPLY CURRENT (µA)
160
280
340
400
75
640
485 G12
220
0 125
460
520
580
–25 25 50 100
DRIVER ENABLED
DRIVER DISABLED
PIN FUNCTIONS
RO (Pin 1): Receiver Output. If the receiver output is en-
abled (RE low), then if A > B by 200mV, RO will be high.
If A < B by 200mV, then RO will be low.
RE (Pin 2): Receiver Output Enable. A low enables the
receiver output, RO. A high input forces the receiver output
into a high impedance state.
DE (Pin 3): Driver Output Enable. A high on DE enables
the driver outputs, A and B, and the chip will function as
a line driver. A low input will force the driver outputs into
a high impedance state and the chip will function as a
line receiver.
DI (Pin 4): Driver Input. If the driver outputs are enabled
(DE high), then a low on DI forces the outputs A low and
B high. A high on DI with the driver outputs enabled will
force A high and B low.
GND (Pin 5): Ground Connection.
A (Pin 6): Driver Output/Receiver Input.
B (Pin 7): Driver Output/Receiver Input.
VCC (Pin 8): Positive Supply; 4.75 < VCC < 5.25.
LTC485
6
485fm
For more information www.linear.com/LTC485
SWITCHING TIME WAVEFORMS
TEST CIRCUITS
VOD
A
B
R
RVOC
485 F01
Figure 1. Driver DC Test Load Figure 2. Receiver Timing Test Load
Figure 3. Driver/Receiver Timing Test Circuit Figure 4. Driver Timing Test Load #2
RECEIVER
OUTPUT
CRL
15pF
1k
S1
S2
TEST POINT
VCC
1k
485 F02
3V
DE
A
B
DI RDIFF
CL1
CL2
RO
15pF
A
B
RE
485 F03
OUTPUT
UNDER TEST
CL
S1
S2
VCC
500Ω
485 F04
Figure 5. Driver Propagation Delays
DI
3V
1.5V
tPLH
tr
tSKEW
1/2 VO
VO
80%
10%
0V
B
A
VO
–VO
0V
90%
1.5V
tPLH
tSKEW
1/2 VO
f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
20%
tf
VDIFF = V(A) – V(B)
485 F05
LTC485
7
485fm
For more information www.linear.com/LTC485
SWITCHING TIME WAVEFORMS
Figure 6. Driver Enable and Disable Times
1.5V
tZL
2.3V
2.3V
tZH
1.5V
tLZ
0.5V
0.5V
tHZ
f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
3V
0V
DI
5V
VOL
VOH
0V
A, B
A, B
485 F06
Figure 7. Receiver Propagation Delays
1.5V
tPHL f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
R
–VOD2
A, B 0V
1.5V
tPLH
OUTPUT
INPUT
VOD2
VOL
VOH
485 F07
Figure 8. Receiver Enable and Disable Times
1.5V
tZL
1.5V
1.5V
tZH
1.5V
tLZ
0.5V
0.5V
tHZ
f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
3V
0V
RE
5V
0V
R
R
485 F08
FUNCTION TABLES
LTC485 Transmitting
INPUTS LINE
CONDITION
OUTPUTS
RE DE DI B A
X 1 1 No Fault 0 1
X 1 0 No Fault 1 0
X 0 X X Z Z
X 1 X Fault Z Z
LTC485 Receiving
INPUTS OUTPUTS
RE DE A – B R
0 0 ≥ 0.2V 1
0 0 ≤ –0.2V 0
0 0 Inputs Open 1
1 0 X Z
LTC485
8
485fm
For more information www.linear.com/LTC485
Basic Theory of Operation
Previous RS485 transceivers have been designed using
bipolar technology because the common mode range
of the device must extend beyond the supplies and the
device must be immune to ESD damage and latchup.
Unfortunately, the bipolar devices draw a large amount of
supply current, which is unacceptable for the numerous
applications that require low power consumption. The
LTC485 is the first CMOS RS485/RS422 transceiver which
features ultralow power consumption without sacrificing
ESD and latchup immunity.
The LTC485 uses a proprietary driver output stage, which
allows a common-mode range that extends beyond the
power supplies while virtually eliminating latchup and
providing excellent ESD protection. Figure 9 shows the
LTC485 output stage while Figure 10 shows a conventional
CMOS output stage.
When the conventional CMOS output stage of Figure 10
enters a high impedance state, both the P-channel (P1)
and the N-channel (N1) are turned off. If the output is
then driven above VCC or below ground, the P + /N-well
Figure 9. LTC485 Output Stage
diode (D1) or the N + /P-substrate diode (D2) respectively
will turn on and clamp the output to the supply. Thus,
the output stage is no longer in a high impedance state
and is not able to meet the RS485 common mode range
requirement. In addition, the large amount of current
flowing through either diode will induce the well known
CMOS latchup condition, which could destroy the device.
The LTC485 output stage of Figure 9 eliminates these
problems by adding two Schottky diodes, SD3 and SD4.
The Schottky diodes are fabricated by a proprietary modi-
fication to the standard N-well CMOS process. When the
output stage is operating normally, the Schottky diodes
are forward biased and have a small voltage drop across
them. When the output is in the high impedance state and
is driven above VCC or below ground, the parasitic diodes
D1 or D2 still turn on, but SD3 or SD4 will reverse bias
and prevent current from flowing into the N-well or the
substrate. Thus, the high impedance state is maintained
even with the output voltage beyond the supplies. With
no minority carrier current flowing into the N-well or
substrate, latchup is virtually eliminated under power-up
or power-down conditions.
APPLICATIONS INFORMATION
Figure 10. Conventional CMOS Output Stage
LOGIC
V
CC
SD3
P1
D1
OUTPUT
SD4
D2
N1
485 F09
LOGIC
V
CC
P1
D1
OUTPUT
D2
N1
485 F10
LTC485
9
485fm
For more information www.linear.com/LTC485
APPLICATIONS INFORMATION
The LTC485 output stage will maintain a high impedance
state until the breakdown of the N-channel or P-channel
is reached when going positive or negative respectively.
The output will be clamped to either VCC or ground by a
Zener voltage plus a Schottky diode drop, but this voltage
is way beyond the RS485 operating range. This clamp
protects the MOS gates from ESD voltages well over
2000V. Because the ESD injected current in the N-well or
substrate consists of majority carriers, latchup is prevented
by careful layout techniques.
Propagation Delay
Many digital encoding schemes are dependent upon the
difference in the propagation delay times of the driver and
the receiver. Using the test circuit of Figure 13, Figures 11
and 12 show the typical LTC485 receiver propagation delay.
The receiver delay times are:
|tPLH – tPHL| = 9ns Typ, VCC = 5V
The driver skew times are:
Skew = 5ns Typ, VCC = 5V
10ns Max, VCC = 5V, TA = –40°C to 85°C
Figure 11. Receiver tPHL
485 F11
DRIVER
OUTPUTS
RECEIVER
OUTPUTS
A
B
RO
Figure 12. Receiver tPLH
485 F12
DRIVER
OUTPUTS
RECEIVER
OUTPUTS
A
B
RO
Figure 13. Receiver Propagation Delay Test Circuit
DRRECEIVER
OUT
R
100Ω
100pF
100pF
TTL IN
tr, tf < 6ns
BR
485 F13
LTC485
10
485fm
For more information www.linear.com/LTC485
LTC485 Line Length vs Data Rate
The maximum line length allowable for the RS422/RS485
standard is 4000 feet.
APPLICATIONS INFORMATION
Figures 17 and 18 show that the LTC485 is able to com-
fortably drive 4000 feet of wire at 110kHz.
Figure 14. Line Length Test Circuit
Figure 16. System Differential Voltage at 19.2kHz
Figure 17. System Common Mode Voltage at 110kHz
485 F15
COMMON MODE
VOLTAGE (A + B)/2
RO
DI
485 F16
DIFFERENTIAL
VOLTAGE A – B
RO
DI
485 F17
COMMON MODE
VOLTAGE (A + B)/2
RO
DI
Figure 18. System Differential Voltage at 110kHz
Figure 19. Cable Length vs Maximum Data Rate
485 F18
DIFFERENTIAL
VOLTAGE (A – B)
RO
DI
MAXIMUM DATA RATE
10k
10
CABLE LENGTH (FT)
100
1k
10k
100k 1M 10M
485 F19
2.5M
Figure 15. System Common Mode Voltage at 19.2kHz
TTL
OUT
LTC485LTC485
NOISE
GENERATOR
100Ω
C
D
4000 FT 26AWG
TWISTED PAIR
A
B
TTL
IN
485 F14
When specifying line length vs maximum data rate the
curve in Figure 19 should be used.
Using the test circuit in Figure 14, Figures 15 and 16 show
that with ~20VP-P common mode noise injected on the
line, the LTC485 is able to reconstruct the data stream at
the end of 4000 feet of twisted pair wire.
LTC485
11
485fm
For more information www.linear.com/LTC485
OBSOLETE PACKAGE
TYPICAL APPLICATION
Typical RS485 Network
R
t
485 TA02
R
t
PACKAGE DESCRIPTION
J8 0801
.014 – .026
(0.360 – 0.660)
.200
(5.080)
MAX
.015 – .060
(0.381 – 1.524)
.125
3.175
MIN
.100
(2.54)
BSC
.300 BSC
(7.62 BSC)
.008 – .018
(0.203 – 0.457) 0° – 15°
.005
(0.127)
MIN
.405
(10.287)
MAX
.220 – .310
(5.588 – 7.874)
1 2 34
8 7 6 5
.025
(0.635)
RAD TYP
.045 – .068
(1.143 – 1.650)
FULL LEAD
OPTION
.023 – .045
(0.584 – 1.143)
HALF LEAD
OPTION
CORNER LEADS OPTION
(4 PLCS)
.045 – .065
(1.143 – 1.651)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE
OR TIN PLATE LEADS
J8 Package
8-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
Please refer to http://www.linear.com/product/LTC485#packaging for the most recent package drawings.
LTC485
12
485fm
For more information www.linear.com/LTC485
PACKAGE DESCRIPTION
.016 – .050
(0.406 – 1.270)
.010 – .020
(0.254 – 0.508)× 45°
0°– 8° TYP
.008 – .010
(0.203 – 0.254)
SO8 REV G 0212
.053 – .069
(1.346 – 1.752)
.014 – .019
(0.355 – 0.483)
TYP
.004 – .010
(0.101 – 0.254)
.050
(1.270)
BSC
1234
.150 – .157
(3.810 – 3.988)
NOTE 3
8765
.189 – .197
(4.801 – 5.004)
NOTE 3
.228 – .244
(5.791 – 6.197)
.245
MIN .160 ±.005
RECOMMENDED SOLDER PAD LAYOUT
.045 ±.005
.050 BSC
.030 ±.005
TYP
INCHES
(MILLIMETERS)
NOTE:
1. DIMENSIONS IN
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
4. PIN 1 CAN BE BEVEL EDGE OR A DIMPLE
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610 Rev G)
N8 REV I 0711
.065
(1.651)
TYP
.045 – .065
(1.143 – 1.651)
.130 ±.005
(3.302 ±0.127)
.020
(0.508)
MIN
.018 ±.003
(0.457 ±0.076)
.120
(3.048)
MIN
.008 – .015
(0.203 – 0.381)
.300 – .325
(7.620 – 8.255)
.325 +.035
–.015
+0.889
–0.381
8.255
( )
1 2 34
87 65
.255 ±.015*
(6.477 ±0.381)
.400*
(10.160)
MAX
NOTE:
1. DIMENSIONS ARE INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
.100
(2.54)
BSC
N Package
8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510 Rev I)
Please refer to http://www.linear.com/product/LTC485#packaging for the most recent package drawings.
LTC485
13
485fm
For more information www.linear.com/LTC485
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
REVISION HISTORY
REV DATE DESCRIPTION PAGE NUMBER
I 4/11 Removed lead free version of LTC485MJ8 from Order Information section. 2
J 01/14 Modified to account for high temperature leakage in M-grade. 1, 3
K 02/14 Remove tape and reel option for DIP package in Order Information section. 2
L 07/16 Added storage temperature 2
M 02/17 Obsoleted J8 package 1-14
(Revision history begins at Rev I)
LTC485
14
485fm
For more information www.linear.com/LTC485
LINEAR TECHNOLOGY CORPORATION 1994
LT 0217 REV M • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LTC485
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