LTC1698
U W
TYPICAL PERFOR A CE CHARACTERISTICS
SYNC Positive Threshold
vs Temperature
SYNC Positive Threshold
vs VDD
IVDD vs SYNC Frequency
2.20
1.96
2.25
2.00
50
45
40
35
30
25
20
15
10
5
T
A
= 25°C
V
DD
= 8V
V
A
= 8V
DD
T
= 25°C
C
= C = 4700pF
CG
FG
C
= C = 3300pF
CG
FG
C
= C = 2200pF
CG
FG
1.72
1.75
1.50
1.25
1.48
1.24
1.00
C
= C = 1000pF
CG
FG
1.00
0
5
6
7
8
9
V
10 11 12 13 14
(V)
DD
50 100 150 200 250 300 350 400 450 500
(kHz)
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
1698 G20
f
SYNC
1698 G21
1698 G19
Undervoltage Lockout Threshold
vs Temperature
Opto Driver Short-Circuit Current
vs VDD
IVDD vs VDD
5
4
3
2
1
0
0
–10
–20
20
18
16
14
12
10
8
T
= 25°C
OPTODRV
T
f
= 25°C
SYNC
A
A
C
= C = 4700pF
CG
V
= 1.233V
FG
= 100kHz
C
= C = 3300pF
CG
FG
–30
–40
–50
6
C
= C = 2200pF
CG
FG
4
C
= C = 1000pF
CG
FG
2
0
50
TEMPERATURE (°C)
–50 –25
0
25
75 100 125 150
9
6
7
11 12
5
6
7
8
10 11 12 13 14
(V)
5
8
9
V
10
13 14
V
(V)
DD
DD
1698 G24
1698 G17
1698 G18
Driver Rise, Fall and Propagation
Delay vs Driver Load
SYNC Input to Driver Output Delay
vs Temperature
Driver Disable Time-Out vs SYNC
Frequency
90
80
70
60
50
40
30
20
10
0
90
80
70
60
50
40
30
20
10
0
2.2
30
25
20
15
10
5
V
A
= 8V
V
C
f
= 8V
FG
V
A
= 8V
DD
= 25°C
DD
CG
DD
T
= C = 1000pF
T
= 25°C
= 100kHz
2.0
1.8
1.6
1.4
1.2
1.0
SYNC
CG, FG t
PLH
t
× f
SYNC
DISS
CG, FG t
PLH
t
f
t
r
CG, FG t
CG, FG t
PHL
PHL
t
DISS
0
0
8000 10000
2000
4000
6000
–50 –25
0
25 50 75 100 125 150
50 100 150 200 250 300 350 400 450 500
(kHz)
DRIVER LOAD (pF)
TEMPERATURE (°C)
f
SYNC
1698 G25
1698 G26
1698 G27
1698f
6
Linear [ Linear ]
