LTC2872
Typical perForMance characTerisTics
V
CC
Supply Current vs Supply
Voltage in Shutdown Mode
30
25
SUPPLY CURRENT (mA)
INPUT CURRENET (µA)
20
15
H/F LOW
10
5
0
H/F HIGH
4.6
4.4
85°C
25°C
SUPPLY CURRENT (mA)
4.2
4.0
3.8
3.6
3.4
3.2
3
3.5
4.5
4
INPUT VOLTAGE (V)
5
5.5
2872 G01
V
CC
Supply Current vs Supply
Voltage in Fast Enable Mode
200
V
CC
Supply Current
vs RS485 Data Rate
ALL RS485 DRIVERS AND
180 RECEIVERS SWITCHING.
Y TIED TO A; Z TIED TO B,
160
H/F = 0V, C
L
= 100pF
140 ON Y AND Z TO GND
120
100
80
60
40
20
TERMINATION DISABLED
DRIVER AND RECEIVER
TERMINATION ENABLED
V
CC
= 5V
V
CC
= 3.3V
–40°C
3.0
3
3.5
4
4.5
SUPPLY VOLTAGE (V)
5
5.5
2872 G02
0
0.1
10
1
DATA RATE (Mbps)
100
2872 G03
V
CC
Supply Current
vs RS232 Data Rate
50
45
INPUT CURRENT (mA)
40
35
30
25
20
15
10
0
2.5nF
0.05nF
0.5nF
0.05nF
50 100 150 200 250 300 350 400 450 500
DATA RATE (kbps)
2872 G04
V
CC
Supply Current
vs Supply Voltage for RS485
at Maximum Data Rate
V
CC
= 5V
V
CC
= 3.3V
SUPPLY CURRENT (mA)
240
BOTH RS485 DRIVERS AND
RECEIVERS SWITCHING.
220
Y TIED TO A, Z TIED TO B
H/F = 0V
200
DRIVER AND RECEIVER
TERMINATION ENABLED
180 20Mbps, C = 100pF ON
L
Y AND Z TO GND
160
140
120
100
80
3
3.5
4
4.5
SUPPLY VOLTAGE (V)
5
85°C
25°C
–40°C
5.5
2872 G05
RS485 Driver Differential Output
Voltage vs Temperature
4.5
4.0
3.5
VOLTAGE (V)
3.0
2.5
2.0
1.5
1.0
0.5
0
–50
–25
0
25
50
TEMPERATURE (°C)
V
CC
= 5V
V
CC
= 3.3V
75
100
2872 G06
ALL RS232 DRIVERS
AND RECEIVERS
SWITCHING
2.5nF
R
L
= 100Ω
R
L
= 54Ω
R
L
= 100Ω
R
L
= 54Ω
0.5nF
RS485 Driver Propagation Delay
vs Temperature
50
V
CC
= 3.3V, V
L
= 1.7V
V
CC
= 5V, V
L
= 1.7V
V
CC
= 3.3V, V
L
= 3.3V
V
CC
= 5V, V
L
= 5V
150
SHORT-CIRCUIT CURRENT (mA)
100
50
0
–50
RS485 Driver Short-Circuit Current
vs Short-Circuit Voltage
V
CC
= 5V
V
CC
= 3.3V
3.0
2.5
2.0
SKEW (ns)
RS485 Driver and Receiver Skew
vs Temperature
40
OUTPUT LOW
DELAY (ns)
30
DRIVER
1.5
1.0
20
10
OUTPUT HIGH
–100
–150
–10
0.5
0
–50
RECEIVER
0
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2872 G07
–5
10
0
5
SHORT-CIRCUIT VOLTAGE (V)
15
2872 G08
–25
50
0
25
TEMPERATURE (°C)
75
100
2872 G09
2872f
6
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
