Typical operating characteristics—vcsel driver – Rainbow Electronics MAX3798 User Manual
Page 11
MAX3798
1.0625Gbps to 10.32Gbps, Integrated, Low-
Power SFP+ Limiting Amplifier and VCSEL Driver
______________________________________________________________________________________
11
Typical Operating Characteristics—VCSEL Driver
(V
CC
= 3.3V, T
A
= +25°C, unless otherwise specified. Figure 1 shows the typical setup used for measurements. Registers are set to
default values unless otherwise noted, and the 3-wire interface is static during measurements. For testing, the MODE_SEL bit was
used and the MSEL pin was left open.)
TOTAL SUPPLY CURRENT
vs. TEMPERATURE
MAX3798 toc17
TEMPERATURE (
°C)
SUPPLY CURRENT (mA)
80
65
35
50
-10
5
20
-25
50
60
70
80
90
100
110
120
130
140
40
-40
95
I
BIAS
= 12mA
I
BIAS
= 9mA
I
BIAS
= 2mA
I
MOD
= 2mA; RECEIVER OUTPUT = 400mV
P-P
;
TOTAL SUPPLY MEASURED USING THE SETUP
IN FIGURE 1.
TOTAL SUPPLY CURRENT
vs. TEMPERATURE
MAX3798 toc18
TEMPERATURE (
°C)
SUPPLY CURRENT (mA)
80
65
35
50
-10
5
20
-25
50
60
70
80
90
100
110
120
130
140
150
160
40
-40
95
I
MOD
= 12mA
I
MOD
= 9mA
I
MOD
= 2mA
I
BIAS
= 2mA; RECEIVER OUTPUT = 400mV
P-P
;
TOTAL SUPPLY MEASURED USING THE SETUP
IN FIGURE 1.
OPTICAL EYE DIAGRAM
MAX3798 toc19
14ps/div
10.3Gbps, SET_IMOD = 60, 2
7
- 1 PRBS,
850nm VCSEL, MASK WITH 44%
OPTICAL EYE DIAGRAM
MAX3798 toc20
17ps/div
8.5Gbps, SET_IMOD = 60, 2
7
- 1 PRBS,
850nm VCSEL, MASK WITH 54%
OPTICAL EYE DIAGRAM
MAX3798 toc21
34ps/div
4.25Gbps, SET_IMOD = 60, 2
7
- 1 PRBS,
850nm VCSEL, MASK WITH 46%
OPTICAL EYE DIAGRAM
MAX3798 toc22
68ps/div
2.125Gbps, SET_IMOD = 60, 2
7
- 1 PRBS,
850nm VCSEL, MASK WITH 50%
DETERMINISTIC JITTER
vs. MODULATION CURRENT
MAX3798 toc23
MODULATION CURRENT (mA
P-P
)
DETERMINISTIC JITTER (ps)
10
8
6
4
5.0
5.5
6.0
6.5
7.0
7.5
8.0
4.5
2
12
PATTERN = PRBS, DATA RATE = 10.32Gbps
TRANSITION TIME
vs. MODULATION CURRENT
MAX3798 toc24
MODULATION CURRENT (mA
P-P
)
TRANSITION TIME (ps)
10
8
6
4
8
13
18
23
28
33
38
3
2
12
FALL TIME
RISE TIME
PATTERN = 11110000,
DATA RATE = 8.5Gbps
TRANSITION TIME
vs. DEEMPHASIS SETTING
MAX3798 toc25
SET_TXDE[3:0]
TRANSITION TIME (ps)
10
9
1
2
3
5
6
7
4
8
27
29
31
33
35
37
39
41
25
0
11
FALL TIME
RISE TIME
PATTERN = 11110000,
DATA RATE = 8.5Gbps,
I
MOD
= 10mA
P-P