EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
T
JMAX
= 125°C,
θ
JA
= 43°C/W,
θ
JC
= 3°C/W
T
JMAX
= 125°C,
θ
JA
= 200°C/W,
θ
JC
= 40°C/W
DD PACKAGE
8-LEAD (3mm
3mm) PLASTIC DFN
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
T
JMAX
= 125°C,
θ
JA
= 43°C/W,
θ
JC
= 3°C/W
ORDER
PART NUMBER
LTC2856CDD-1
LTC2856IDD-1
LTC2856CDD-2
LTC2856IDD-2
TOP VIEW
V
CC
RO
DI
GND
1
2
3
4
DD PART
MARKING*
LCMG
LCMG
LCMJ
LCMJ
ORDER
PART NUMBER
LTC2856CMS8-1
LTC2856IMS8-1
LTC2856CMS8-2
LTC2856IMS8-2
TOP VIEW
RO
1
2
3
4
5
11
MS8 PART
MARKING*
LTCMF
LTCMF
LTCMH
LTCMH
10 V
CC
9 A
8 B
7 Z
6 Y
ORDER
PART NUMBER
LTC2857CDD-1
LTC2857IDD-1
LTC2857CDD-2
LTC2857IDD-2
TOP VIEW
RO
RE
DE
DI
GND
1
2
3
4
5
DD PART
MARKING*
LCMD
LCMD
LCMM
LCMM
8
7
6
5
A
B
Z
Y
RE
DE
DI
GND
10
9
8
7
6
V
CC
A
B
Z
Y
MS8 PACKAGE
8-LEAD PLASTIC MSOP
T
JMAX
= 125°C,
θ
JA
= 200°C/W,
θ
JC
= 40°C/W
DD PACKAGE
10-LEAD (3mm
×
3mm) PLASTIC DFN
MS PACKAGE
10-LEAD PLASTIC MSOP
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
T
JMAX
= 125°C,
θ
JA
= 43°C/W,
θ
JC
= 3°C/W
T
JMAX
= 125°C,
θ
JA
= 120°C/W,
θ
JC
= 45°C/W
ORDER
PART NUMBER
LTC2857CMS8-1
LTC2857IMS8-1
LTC2857CMS8-2
LTC2857IMS8-2
MS8 PART
MARKING*
LTCMC
LTCMC
LTCMK
LTCMK
ORDER
PART NUMBER
LTC2858CDD-1
LTC2858IDD-1
LTC2858CDD-2
LTC2858IDD-2
DD PART
MARKING*
LCGR
LCGR
LCMR
LCMR
ORDER
PART NUMBER
LTC2858CMS-1
LTC2858IMS-1
LTC2858CMS-2
LTC2858IMS-2
MS PART
MARKING*
LTCGQ
LTCGQ
LTCMQ
LTCMQ
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
285678fb
2
LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
ELECTRICAL CHARACTERISTICS
SYMBOL
Driver
|V
OD
|
Differential Driver Output Voltage
R = ∞, I
O
= 0mA, V
CC
= 4.5V (Figure 1)
R = 27Ω (RS485), V
CC
= 4.5V (Figure 1)
R = 50Ω (RS422), V
CC
= 4.5V (Figure 1)
Δ|V
OD
|
V
OC
Δ|V
OC
|
I
OZD
I
OSD
Receiver
I
IN
Receiver Input Current (A, B)
DE = 0V, V
CC
= 0V or 5V, V
IN
= 12V
(Figure 3)
DE = 0V, V
CC
= 0V or 5V, V
IN
= –7V
(Figure 3)
RE = 5V or 0V, DE = 0V, V
IN
= –7V, –3V,
3V, 7V, 12V (Figure 3)
–7V ≤ V
CM
≤ 12V
V
CM
= 0V
I
O
= –4mA, V
ID
= 200mV, V
CC
= 4.5V
I
O
= 4mA, V
ID
= –200mV, V
CC
= 4.5V
RE = 5V, 0V ≤ V
O
≤ V
CC
, LTC2856-1,
LTC2856-2, LTC2858-1, LTC2858-2
DE, DI, RE, V
CC
= 5.5V
DE, DI, RE, V
CC
= 4.5V
DE, DI, RE
DE = 0V, RE = V
CC
, LTC2856-1,
LTC2856-2, LTC2858-1, LTC2858-2
No Load, DE = 0V, RE = 0V, LTC2856-1,
LTC2856-2, LTC2858-1, LTC2858-2
No Load, DE = V
CC
, LTC2856-1
RE = V
CC
LTC2858-1
LTC2856-2
LTC2858-2
No Load, DE = V
CC
, LTC2856-1
RE = 0V
LTC2857-1
LTC2858-1
LTC2856-2
LTC2857-2
LTC2858-2
●
●
●
●
●
●
●
●
●
●
●
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V unless otherwise noted. (Note 2)
PARAMETER
CONDITIONS
MIN
TYP
MAX
V
CC
1.5
2
V
CC
V
CC
0.2
3
0.2
±10
±120
±250
125
–100
96
125
±0.2
25
2.4
0.4
±1
UNITS
V
V
V
V
V
V
µA
mA
µA
µA
kΩ
V
mV
V
V
µA
Change in Magnitude of Driver Differential
Output Voltage for Complementary Output
States
Driver Common Mode Output Voltage
Change in Magnitude of Driver Common Mode
Output Voltage for Complementary Output
States
Driver Three-State (High Impedance) Output
Current on Y and Z
Maximum Driver Short-Circuit Current
R = 27Ω or R = 50Ω (Figure 1)
R = 27Ω or R = 50Ω (Figure 1)
R = 27Ω or R = 50Ω (Figure 1)
DE = 0V, V
O
= –7V, 12V, LTC2858-1,
LTC2858-2
–7V ≤ (Y or Z) ≤ 12V (Figure 2)
●
●
●
●
R
IN
V
TH
ΔV
TH
V
OH
V
OL
I
OZR
Logic
V
IH
V
IL
I
INL
Supplies
I
CCS
I
CCR
I
CCT
Receiver Input Resistance
Receiver Differential Input Threshold Voltage
Receiver Input Hysteresis
Receiver Output High Voltage
Receiver Output Low Voltage
Receiver Three-State (High Impedance) Output
Current on RO
Logic Input High Voltage
Logic Input Low Voltage
Logic Input Current
Supply Current in Shutdown Mode
Supply Current in Receive Mode
Supply Current in Transmit Mode
●
●
●
2
0.8
0
0
540
630
670
660
700
±10
5
900
1000
1100
1100
1200
V
V
µA
µA
µA
µA
µA
µA
µA
●
●
●
●
●
I
CCTR
Supply Current with Both Driver and Receiver
Enabled
●
285678fb
3
LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
SWITCHING CHARACTERISTICS
SYMBOL
f
MAX
t
PLHD
, t
PHLD
Δt
PD
t
SKEWD
t
RD
, t
FD
t
ZLD
, t
ZHD
,
t
LZD
, t
HZD
t
ZHSD
, t
ZLSD
t
SHDN
PARAMETER
Maximum Data Rate
Driver Input to Output
Driver Output Y to Output Z
Driver Rise or Fall Time
Driver Enable or Disable Time
Driver Enable from Shutdown
Time to Shutdown
Driver in LTC2856-1, LTC2857-1, LTC2858-1
(Note 3)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
L
= 500Ω, C
L
= 50pF, RE = 0V,
LTC2856-1, LTC2858-1 (Figure 5)
R
L
= 500Ω, C
L
= 50pF, RE = V
CC
,
LTC2856-1, LTC2858-1 (Figure 5)
(DE =
↓,
RE = V
CC
) or (DE = 0V, RE =
↑),
LTC2856-1, LTC2858-1 (Figure 5)
(Note 3)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
R
L
= 500Ω, C
L
= 50pF, RE = 0V,
LTC2856-2, LTC2858-2 (Figure 5)
R
L
= 500Ω, C
L
= 50pF, RE = 0V,
LTC2856-2, LTC2858-2 (Figure 5)
R
L
= 500Ω, C
L
50pF, RE = V
CC
,
LTC2856-2, LTC2858-2 (Figure 5)
(DE = 0V, RE↑) or (DE =
↓,
RE = V
CC
),
LTC2856-2, LTC2858-2 (Figure 5)
C
L
= 15pF, V
CM
= 1.5V, |V
AB
| = 1.5V,
t
R
and t
F
< 4ns (Figure 6)
C
L
= 15pF (Figure 6)
C
L
= 15pF (Figure 6)
R
L
= 1k, C
L
= 15pF, DE = V
CC
,
LTC2856-1, LTC2856-2, LTC2858-1,
LTC2858-2 (Figure 7)
R
L
= 1k, C
L
= 15pF, DE = 0V,
LTC2856-1, LTC2856-2, LTC2858-1,
LTC2858-2 (Figure 7)
●
●
●
●
●
●
●
●
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V unless otherwise noted. (Note 2)
CONDITIONS
MIN
20
10
1
1
4
50
6
±6
12.5
70
8
100
TYP
MAX
UNITS
Mbps
ns
ns
ns
ns
ns
µs
ns
Driver Input to Output Difference |t
PLHD
– t
PHLD
| R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
Driver in LTC2856-2, LTC2857-2, LTC2858-2
f
MAXS
Δt
PDS
t
SKEWDS
t
RDS
, t
FDS
t
ZHDS
, t
ZLDS
t
LZDS
, t
HZDS
Maximum Data Rate
●
●
●
●
●
●
●
●
●
250
0.95
50
200
0.90
1.5
500
±500
1.5
300
70
8
500
kbps
µs
ns
ns
µs
ns
ns
µs
ns
t
PLHDS
, t
PHLDS
Driver Input to Output
Driver Output A to Output B
Driver Rise or Fall Time
Driver Enable Time
Driver Disable Time
Driver Input to Output Difference |t
PLHD
– t
PHLD
| R
DIFF
= 54Ω, C
L
= 100pF (Figure 4)
t
ZHSDS
, t
ZLSDS
Driver Enable from Shutdown
t
SHDNS
Receiver
t
PLHR
, t
PHLR
t
SKEWR
t
RR
, t
FR
t
ZLR
, t
ZHR
,
t
LZR
, t
HZR
t
ZHSR
, t
ZLSR
Receiver Input to Output
Differential Receiver Skew, |t
PLHR
– t
PHLR
|
Receiver Output Rise or Fall Time
Receiver Enable/Disable
Receiver Enable from Shutdown
Time to Shutdown
●
●
●
●
50
1
3
70
6
12.5
50
8
ns
ns
ns
ns
µs
●
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.
Note 3:
Maximum data rate is guaranteed by other measured parameters
and is not tested directly.
Note 4:
This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may result in device degradation or failure.
285678fb
4
LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
TEST CIRCUITS
Y
GND
OR
V
CC
DI
Y
DRIVER
V
OD
+
R
R
–
Z
V
OC
+
–
GND
OR
V
CC
DI
I
OSD
DRIVER
Z
+
–
285678 F02
–7V TO +12V
285678 F01
Figure 1. Driver DC Characteristics
I
IN
Figure 2. Driver Output Short-Circuit Current
A OR B
RECEIVER
V
IN
+
–
B OR A
285678 F03
V
R
IN
=
IN
I
IN
Figure 3. Receiver Input Current and Input Resistance
Y
DI
C
L
DRIVER
R
DIFF
C
L
Z
285678 F04a
DI
V
CC
0V
t
PLHD,
t
PLHDS
t
PHLD,
t
PHLDS
t
SKEWD,
t
SKEWDS
Y, Z
V
O
1/2 V
O
Y-Z
90%
10%
0
t
RD,
t
RDS
0
90%
10%
t
FD,
t
FDS
285678 F04b
Figure 4. Driver Timing Measurement
Y
V
CC
OR
GND
DI
C
L
DRIVER
DE
R
L
GND
OR
V
CC
DE
V
CC
0V
V
CC
V
OL
V
O
1/2 V
CC
t
ZLD,
t
ZLDS,
t
ZLSD,
t
ZLSDS
1/2 V
CC
t
LZD,
t
LZDS
0.5V
0.5V
t
HZD,
t
HZDS,
t
SHDN,
t
SHDNS
285678 F05b
Y OR Z
R
L
Z
C
L
V
CC
OR
GND
285678 F05a
Z OR Y
V
OH
0V
t
ZHD,
t
ZHDS,
t
ZHSD,
t
ZHSDS
1/2 V
CC
Figure 5. Driver Enable and Disable Timing Measurement
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