LTC2846 Linear Technology, LTC2846 Datasheet - Page 10

• Manufacturer Part Number: LTC2846
• Description: 3.3V Software-Selectable Multiprotocol Transceiver with Termination
• Manufacturer: Linear Technology

www.DataSheet4U.com
DataSheet U .com
W
Mode Name M2 M1 M0 DCE/ D1,2 D3
Not Used
(Default V.11) 0
RS530A
RS530
X.21
V.35
RS449/V.36
V.28/RS232
No Cable
Not Used
(Default V.11) 0
RS530A
RS530
X.21
V.35
RS449/V.36
V.28/RS232
No Cable
SWITCHI G TI E WAVEFOR S
LTC2846
Table 1
Note 1: Driver inputs are TTL level compatible.
Note 2: Unused receiver inputs are terminated with 30k to ground. In addition, R2 and R3 are always
terminated by a 103 differential impedence (see Block Diagram on page 8).
Note 3: Receiver Outputs are CMOS level compatible and have a weak pull up to V
10
4
ODE SELECTIO
B – A
B – A
–V
D
V
R
–V
V
OD2
OD2
V
3V
0V
V
OH
OL
O
O
A
B
0
0
0
1
1
1
1
0
0
0
1
1
1
1
U
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
V
O
DTE
W
0
1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
TTL X
TTL X
TTL X
TTL X
TTL X
TTL X
TTL X
TTL TTL V.11 V.11 V.11 V.11 V.11 V.11 30k 30k V.11 V.11 V.11 V.11
TTL TTL V.11 V.11 V.11 V.11 V.11 V.11 30k 30k V.11 V.11 V.11 V.11
TTL TTL V.11 V.11 V.11 V.11 V.11 V.11 30k 30k V.11 V.11 V.11 V.11
TTL TTL V.11 V.11 V.11 V.11 V.11 V.11 30k 30k V.11 V.11 V.11 V.11
TTL TTL V.35 V.35 V.35 V.35 V.35 V.35 30k 30k V.35 V.35 V.35 V.35
TTL TTL V.11 V.11 V.11 V.11 V.11 V.11 30k 30k V.11 V.11 V.11 V.11
TTL TTL V.28
X
X
U
1.5V
0V
t
t
PLH
PLH
50%
X
X
V.11 V.11 V.11 V.11
V.11 V.11 V.11 V.11
V.11 V.11 V.11 V.11
V.11 V.11 V.11 V.11
V.35 V.35 V.35 V.35
V.11 V.11 V.11 V.11
V.28
t
A
Z
Z
r
Figure 14. V.11, V.35 Receiver Propagation Delays
D1
Figure 13. V.11, V.35 Driver Propagation Delays
1.65V
t
10%
90%
SKEW
B
Z
Z
Z
Z
V.28
V.28
1/2 V
A
Z
Z
W
D2
f = 1MHz : t
f = 1MHz : t
IN
O
when Z.
B
Z
Z
Z
Z
V.28
r
r
A
Z
Z
Z
Z
Z
Z
Z
Z
Z
D3
10ns : t
10ns : t
B
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Note 4: V
under full load for each mode.
Note 5: V
under full load for each mode.
f
f
V.11 V.11 V.11 V.11 V.11 V.11 CMOS
V.11 V.11 V.11 V.11 V.11 V.11 CMOS
V.11 V.11 V.11 V.11 V.11 V.11 CMOS
V.11 V.11 V.11 V.11 V.11 V.11 CMOS
V.35 V.35 V.35 V.35 V.35 V.35 CMOS
V.11 V.11 V.11 V.11 V.11 V.11 CMOS
V.28 30k V.28 30k V.28 30k CMOS
30k 30k 30k 30k
30k 30k V.28 30k V.28 30k
30k 30k 30k 30k
10ns
10ns
A
(Note 2)
R1
DD
EE
values shown are typical values for V
values shown are typical values for V
B
A
(Note 2)
OUTPUT
R2
INPUT
B
30k 30k
30k 30k
A
(Note 2)
R3
1.5V
0V
t
90%
t
PHL
PHL
B
CC
CC
= 5V, V
= 5V, V
(Note 3)
t
f
R1
Z
Z
Z
Z
Z
Z
Z
Z
Z
1.65V
50%
IN
IN
t
SKEW
= 3.3V and T
= 3.3V and T
R2,R3
(Note 3)
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
10%
Z
Z
A
A
= 25 C with LTC2846
= 25 C with LTC2846
(Note 4)
9.3V
9.3V
9.3V
9.3V
9.3V
8.7V
4.7V
9.3V
9.3V
9.3V
9.3V
9.3V
8.7V
4.7V
V
8V
8V
2846 F13
2846 F14
DD
sn2846 2846fs
(Note 5)
–6.5V
–8.5V
–6.5V
–8.5V
0.3V
0.3V
–6V
–6V
–6V
–6V
–6V
–6V
–6V
–6V
–6V
–6V
V
EE