MAX3658AETA+T Maxim Integrated Products, MAX3658AETA+T Datasheet - Page 9

• Manufacturer Part Number: MAX3658AETA+T
• Description: IC AMP TRANSIMPEDANCE 8-TDFN
• Manufacturer: Maxim Integrated Products
• Type: Transimpedance Amplifierr

Specifications of MAX3658AETA+T

• Applications: Optical Networks
• Mounting Type: Surface Mount
• Package / Case: 8-TDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 4. Optical Power Relations
where ρ is the photodiode responsivity in A/W and i
the RMS noise current in amps. For example, with pho-
todiode responsivity of 0.9A/W, an extinction ratio of 10
and 45nA input-referred noise, the sensitivity of the
MAX3658 is:
Actual results may vary depending on supply noise,
output filter, limiting amplifier sensitivity, and other fac-
tors (refer to application note HFAN-03.0.0: Accurately
Estimating Optical Receiver Sensitivity ).
Maxim obtains -33dBm typ sensitivity combined with
the MAX3748.
Overload is the largest input that the MAX3658 accepts
while meeting the pulse-width distortion specification.
Optical overload can be estimated in terms of average
power with the following equation:
For example, if photodiode responsivity is 1.0A/W, the
input overload is 0dBm.
SENSITIVITY
OVERLOAD
P
AVG
P1
P0
=
=
10
−
34
log
=
_______________________________________________________________________________________
dBm
10
⎛
⎜
⎝
12 7
2
log
.
×
⎛
⎜
⎝
Input Optical Overload
×
0 9
2
TIME
2
.
45
mA
×
A W
nA
/
ρ
×
×
×
11
9
1000
622Mbps, Low-Noise, High-Gain
×
⎞
⎟
⎠
1000
dBm
Transimpedance Preamplifier
⎞
⎟
⎠
dBm
n
is
The MAX3658 has high gain, which limits the output for
large input signals. The MAX3658 operates in a linear
range for inputs not exceeding:
For example, with photodiode responsivity of 0.9A/W
and an extinction ratio of 10, the linear range is:
The MAX3658 has a differential output structure with
75Ω termination (150Ω differential). Figure 5 is a simpli-
fied diagram of the output interface. Common test
equipment is designed with a 50Ω single-ended termi-
nation (100Ω differential). Figures 6a and 6b show alter-
nate interface schemes for the MAX3658.
Figure 5. Equivalent Output Interface
LINEAR RANGE
LINEARRANGE
R
75Ω
OUT
=
V
=
=
CC
10
10
Equivalent Output Interface
−
log
Interface Schematics
25
log
⎛
⎜
⎜
⎝
dBm
R
75Ω
2
⎛
⎜
⎝
OUT
4
2
μ
×
4
A
×
Optical Linear Range
μ
V
ρ
CC
×
A
0 9
×
.
(
×
r
(
e
r
e
×
11
+
OUT+
−
1
9
1
)
)
×
×
V
1000
CC
1000
⎞
⎟
⎠
⎞
⎟
⎟
⎠
OUT-
dBm
dBm
9