Operating Temperature Range ........................... -40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10s) ................................. +300°C
Soldering Temperature (reflow) ....................................... +260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Thermal Characteristics
(Note 1)
Junction-to-Ambient Thermal Resistance (θ
JA
) ..............71°C/W
Junction-to-Case Thermal Resistance (θ
JC
) ...................23°C/W
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-tutorial.
DC Electrical Characteristics
(V
DDA
– V
GNDA
= 1.71V to 5.5V, V
DDB
– V
GNDB
= 4.5V to 5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
V
DDA
– V
GNDA
= 3.3V, V
DDB
– V
GNDB
= 5V, V
GNDA
= V
GNDB
, and T
A
= +25°C.) (Notes 2, 3)
PARAMETER
POWER
Supply Voltage
V
DDA
V
DDB
I
DDA
I
DDB
Undervoltage-Lockout Threshold
Undervoltage-Lockout
Threshold Hysteresis
LDO
LDO Supply Voltage
LDO Supply Current
LDO Output Voltage
LDO Current Limit
Load Regulation
Line Regulation
VLDO = 5.68V, ILOAD = 20mA to
40mA
VLDO = 5.68V to 14V, ILOAD = 20mA
VLDO
ILDO
VDDB
Relative to GNDB, LDO is on (Note 4)
DE = high,
RE
= TXD = low, no load,
VLDO = 5.5V
4.5
4.68
6.5
5
300
0.19
0.12
1.7
1.8
14
12.9
5.5
V
mA
V
mA
mV/mA
mV/V
V
UVLOA
V
UVLOB
V
UVHYSTA
V
UVHYSTB
VDDA = 5V, DE = high,
RE
= TXD =
low, RXD unconnected, no load
DE = high,
RE
= TXD = low, RXD
unconnected, no load, VDDB = 5V
VDDA rising
VDDB rising
1.50
2.55
1.71
4.5
4
6.3
1.58
2.7
50
200
5.5
5.5
6.6
mA
12.5
1.65
2.85
V
mV
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Current
www.maximintegrated.com
Maxim Integrated
│
2
MAX14945
2.75kV
RMS
Isolated 500kbps Half-Duplex RS-485/
RS-422 Transceiver with ±30kV ESD Protection
DC Electrical Characteristics (continued)
(V
DDA
– V
GNDA
= 1.71V to 5.5V, V
DDB
– V
GNDB
= 4.5V to 5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
V
DDA
– V
GNDA
= 3.3V, V
DDB
– V
GNDB
= 5V, V
GNDA
= V
GNDB
, and T
A
= +25°C.) (Notes 2, 3)
PARAMETER
Dropout Voltage
LOGIC INTERFACE (TXD, RXD, DE,
RE, SBA)
Input High Voltage
VIH
Load Capacitance
SYMBOL
CONDITIONS
VLDO = 4.68V, IDDB = -120mA
Nominal value
2.25V
≤ V
DDA
≤
5.5V
1.71V
≤ V
DDA
≤
1.89V
2.25V
≤ V
DDA
≤
5.5V
1.71V
≤ V
DDA
≤
1.89V
220
2
-10
1.5
3
RXD to GNDA, IOUT = -4mA
RXD to GNDA, IOUT = 4mA
Output Voltage Low
Short-Circuit Output Pullup
Current
Short-Circuit Output Pulldown
Current
Three-State Output Current
DRIVER
RL
= 54Ω, TXD = high or low,
Figure 1a
Differential Driver Output
|VOD|
RL
= 100Ω, TXD = high or low,
Figure 1a
-7V
≤
VCM
≤
+12V, Figure 1b
Change in Magnitude of
Differential Driver Output Voltage
Driver Common Mode Output
Voltage
ΔV
OD
VOC
RL
= 54Ω (Note 5)
RL
= 54Ω
V
DDB
/2
2
3
1.5
5
0.2
3
V
V
V
VOL
ISH_PU
ISH_PD
IOZ
SBA
to GNDA, IOUT = 4mA
0V ≤ V
RXD
≤ V
DDA,
RE
= low
0V ≤ V
RXD
≤ V
DDA,
RE
= low
0V ≤ V
SBA
≤ V
DDA, side B is pow-
ered and working
0V ≤ V
RXD
≤ V
DDA,
RE
= high
-1
-42
+40
+60
+1
mA
µA
VDDA
-0.4
0.40
0.45
V
-4.5
4.5
5
-1.5
10
8
1
0.7 x
VDDA
0.78 x
VDDA
0.8
V
0.6
mV
pF
µA
µA
kΩ
V
MIN
TYP
100
MAX
180
10
UNITS
mV
µF
RE,
TXD, DE to
GNDA
V
Input Low Voltage
VIL
VHYS
CIN
IPU
IPD
RSBA
VOH
RE,
TXD, DE to
GNDA
Input Hysteresis
Input Capacitance
Input Pullup Current
Input Pulldown Current
SBA
Pullup Resistance
Output Voltage High
RE,
TXD, DE to GNDA
RE,
TXD, DE, f = 1MHz
TXD
DE,
RE
mA
www.maximintegrated.com
Maxim Integrated
│
3
MAX14945
2.75kV
RMS
Isolated 500kbps Half-Duplex RS-485/
RS-422 Transceiver with ±30kV ESD Protection
DC Electrical Characteristics (continued)
(V
DDA
– V
GNDA
= 1.71V to 5.5V, V
DDB
– V
GNDB
= 4.5V to 5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
V
DDA
– V
GNDA
= 3.3V, V
DDB
– V
GNDB
= 5V, V
GNDA
= V
GNDB
, and T
A
= +25°C.) (Notes 2, 3)
PARAMETER
Change in Magnitude of
Common-Mode Voltage
Driver Short-Circuit Output
Current
SYMBOL
ΔV
OC
CONDITIONS
RL
= 54Ω (Note 5)
GNDB ≤ V
OUT
≤ +12V, output low (Note 6)
-7V ≤ V
OUT
≤ V
DDB, output high (Note 6)
(VDDB
– 1V) ≤ V
OUT
≤ +12V,
output low (Note 6)
-7V ≤ V
OUT
≤ +1V, output high (Note 6)
VIN = +12V
VIN = -7V
-100
-200
-125
15
96
+160
15
Human Body Model
IEC 61000-4-2 Air Gap Discharge
IEC 61000-4-2 Contact Discharge
Human Body Model
±30
±15
±10
±4
kV
kV
-50
+40
-250
+20
mA
-20
MIN
TYP
MAX
0.2
+250
-40
UNITS
V
IOSD
mA
Driver Short-Circuit Foldback
Output Current
RECEIVER
Input Current (A and B)
Receiver Differential Threshold
Voltage
Receiver Input Hysteresis
Receiver Input Resistance
PROTECTION
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
ESD Protection
(A and B Pins to GNDB)
ESD Protection (All Other Pins)
IOSDF
IA, IB
VTH
ΔV
TH
RIN
T
SHDN
T
HYST
DE = low, VDDB
= GNDB or 5.5V
-7V ≤ V
CM
≤ +12V
VCM = 0V
+125
µA
mV
mV
kΩ
°C
°C
-7V ≤ V
CM
≤ +12V, DE = low
Temperature Rising
www.maximintegrated.com
Maxim Integrated
│
4
MAX14945
2.75kV
RMS
Isolated 500kbps Half-Duplex RS-485/
RS-422 Transceiver with ±30kV ESD Protection
Switching Electrical Characteristics
(V
DDA
– V
GNDA
= 1.71V to 5.5V, V
DDB
– V
GNDB
= 4.5V to 5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
V
DDA
– V
GNDA
= 3.3V, V
DDB
– V
GNDB
= 5V, V
GNDA
= V
GNDB
, and T
A
= +25°C.) (Note 7)
PARAMETER
DYNAMIC
Common Mode Transient
Immunity
Glitch Rejection
DRIVER
Driver Propagation Delay
Differential Driver Output Skew
|tDPLH - tDPHL|
Driver Differential Output Rise
or Fall Time
Maximum Data Rate
Driver Enable to Output High
Driver Enable to Output Low
Driver Disable Time from Low
Driver Disable Time from High
RECEIVER
Receiver Propagation Delay
Receiver Output Skew
|tRPLH - tRPHL|
Maximum Data Rate
Receiver Enable to Output High
Receiver Enable to Output Low
Receiver Disable Time From Low
Receiver Disable Time From High
tRPLH, tRPHL CL = 15pF, Figure 6 and 7 (Note 9)
tRSKEW
DRMAX
tRZH
tRZL
tRLZ
tRHZ
CL = 15pF, Figure 6 and 7
(Note 9)
500
RL
= 1kΩ, C
L = 15pF, S2 closed,
Figure 8
RL
= 1kΩ, C
L = 15pF, S1 closed,
Figure 8
RL
= 1kΩ, C
L = 15pF, S1 closed,
Figure 8
RL
= 1kΩ, C
L = 15pF, S2 closed,
Figure 8
20
30
20
20
240
34
ns
ns
kbps
ns
ns
ns
ns
tDPLH, tDPHL
tDSKEW
tLH, tHL
DRMAX
tDZH
tDZL
tDLZ
tDHZ
RL
= 500Ω, C
L = 50pF, Figure 4
RL
= 500Ω, C
L = 50pF, Figure 5
RL
= 500Ω, C
L = 50pF, Figure 5
RL
= 500Ω, C
L = 50pF, Figure 4
RL
= 54Ω, C
L = 50pF, Figure 2 and
Figure 3
RL
= 54Ω, C
L = 50pF, Figure 2 and
Figure 3
R
L
= 54Ω, C
L = 50pF, Figure 2 and
Figure 3
500
2540
2540
140
140
1040
144
900
ns
ns
ns
kbps
ns
ns
ns
ns
CMTI
(Note 8)
TXD, DE, RXD
10
35
17
29
kV/μs
ns
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Note 2:
All devices are 100% production tested at T
A
= +25°C. Specifications over temperature are guaranteed by design.
Note 3:
All currents into the device are positive. All currents out of the device are negative. All voltages are referenced to their
respective ground (GNDA or GNDB), unless otherwise noted.
Note 4:
V
LDO
max indicates voltage capability of the circuit. Power dissipation requirements may limit V
LDO
max to a lower value.
Note 5:
ΔV
OD
and ΔV
OC
are the changes in V
OD
and V
OC
, respectively, when the TXD input changes state.
Note 6:
The short circuit output current applies to the peak current just prior to foldback current limiting.
Note 7:
Not production tested. Guaranteed by design.
Note 8:
CMTI is the maximum sustainable common-mode voltage slew rate while maintaining the correct output states. CMTI
applies to both rising and falling common-mode voltage edges. Tested with the transient generator connected between
GNDA and GNDB.
Note 9:
Capacitive load includes test probe and fixture capacitance.
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Embedded System
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