19-4796; Rev 1; 6/00
KIT
ATION
EVALU
BLE
AVAILA
1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise
Transimpedance Preamplifiers for LANs
General Description
The MAX3266 is a transimpedance preamplifier for
1.25Gbps local area network (LAN) fiber optic
receivers. The circuit features 200nA input-referred
noise, 920MHz bandwidth, and 1mA input overload.
The MAX3267 provides a pin-for-pin compatible solu-
tion for communications up to 2.5Gbps. It features
500nA input-referred noise, 1.9GHz bandwidth, and
1mA input overload.
Both devices operate from a +3.0V to +5.5V single sup-
ply and require no compensation capacitor. They also
include a space-saving filter connection that provides
positive bias for the photodiode through a 1.5kΩ resistor
to V
CC
. These features allow easy assembly into a TO-46
or TO-56 header with a photodiode.
The 1.25Gbps MAX3266 has a typical optical dynamic
range of -24dBm to 0dBm in a shortwave (850nm)
configuration or -27dBm to -3dBm in a longwave
(1300nm) configuration. The 2.5Gbps MAX3267 has a
typical optical dynamic range of -21dBm to 0dBm in a
shortwave configuration or -24dBm to -3dBm in a long-
wave configuration.
Features
o
200nA Input-Referred Noise (MAX3266)
500nA Input-Referred Noise (MAX3267)
o
920MHz Bandwidth (MAX3266)
1900MHz Bandwidth (MAX3267)
o
1mA Input Overload
o
+3.0V to +5.5V Single-Supply Voltage
MAX3266/MAX3267
Ordering Information
PART
MAX3266CSA
MAX3266C/D
MAX3267CSA
MAX3267C/D
MAX3267ESA
MAX3267E/D
TEMP. RANGE
0°C to +70°C
—
0°C to +70°C
—
-40°C to +85°C
—
PIN-PACKAGE
8 SO
Dice*
8 SO
Dice*
8 SO
Dice*
*Dice
are designed to operate over a -40°C to +140°C junction tem-
perature (Tj) range, but are tested and guaranteed at T
A
= +25°C.
Pin Configuration
TOP VIEW
V
CC
1
8
7
GND
OUT+
OUT-
GND
Applications
Gigabit Ethernet
1Gbps to 2.5Gbps Optical Receivers
Fibre Channel
N.C.
IN
2
3
MAX3266
MAX3267
6
5
FILTER
4
SO
Typical Application Circuit
V
CC
0.01µF
1.5k
C
FILTER
400pF
FILTER
PHOTODIODE
IN
OUT+
100Ω
OUT-
V
CC
0.1µF
MAX3266
MAX3267
GND
0.1µF
LIMITING
AMPLIFIER
________________________________________________________________
Maxim Integrated Products
1
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise
Transimpedance Preamplifiers for LANs
MAX3266/MAX3267
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
CC
- GND) .................................-0.5V to +6.0V
IN Current..............................................................-4mA to +4mA
FILTER Current......................................................-8mA to +8mA
Voltage at OUT+, OUT- ...................(V
CC
- 1.5V) to (V
CC
+ 0.5V)
Continuous Power Dissipation (T
A
= +70°C)
8-Pin SO (derate 6.7mW/°C above +70°C)..................533mW
Storage Temperature Range .............................-55°C to +150°C
Operating Junction Temperature (die) ..............-55°C to +150°C
Processing Temperature (die) .........................................+400°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS—MAX3266C/MAX3267C
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +70°C, 100Ω load between OUT+ and OUT-. Typical values are at T
A
= +25°C, V
CC
= 3.3V,
source capacitance = 0.85pF, unless otherwise noted.) (Note 1)
PARAMETER
Input Bias Voltage
Supply Current
Transimpedance
Output Impedance
Maximum Differential Output
Voltage
Filter Resistor
AC Input Overload
DC Input Overload
Die, packaged in TO-56
header (Note 2)
Input-Referred RMS Noise
SO package
(Note 2)
Input-Referred Noise Density
Small-Signal Bandwidth
Low-Frequency Cutoff
Transimpedance Linear Range
Deterministic Jitter
Power-Supply Rejection Ratio
(PSRR)
(Note 2)
MAX3266
MAX3267
-3dB, input
≤
20µA DC
Peak-to-peak,
0.95 < linearity < 1.05
(Note 3)
MAX3266
MAX3267
MAX3266
MAX3267
30
40
19
12
50
76
50
MAX3266
MAX3266
MAX3267
MAX3266
MAX3267
750
1530
Differential, measured
with 30µAp-p signal
(40µAp-p for MAX3267)
Single ended (per side)
Input = 1mAp-p
MAX3266
MAX3267
2260
1540
48
185
1220
1.0
0.65
192
200
485
6.6
11.0
920
1900
44
1100
2420
655
pA/(Hz)
1/2
MHz
kHz
µAp-p
ps
ps
dB
256
nA
CONDITIONS
MIN
0.69
TYP
0.83
26
2800
1900
50
250
1500
MAX
0.91
50
3400
2330
52
415
1860
Ω
mVp-p
Ω
mAp-p
mA
UNITS
V
mA
Ω
Output referred, f < 2MHz,
PSRR = -20log (∆V
OUT
/∆V
CC
)
2
_______________________________________________________________________________________
1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise
Transimpedance Preamplifiers for LANs
ELECTRICAL CHARACTERISTICS—MAX3267E
(V
CC
= +3.0V to +5.5V, T
A
= -40°C to +85°C, 100Ω load between OUT+ and OUT-. Typical values are at T
A
= +25°C, V
CC
= 3.3V,
source capacitance = 0.85pF, unless otherwise noted.) (Note 1)
PARAMETER
Input Bias Voltage
Supply Current
Transimpedance
Output Impedance
Maximum Differential Output
Voltage
Filter Resistor
AC Input Overload
DC Input Overload
Input-Referred RMS Noise
Input-Referred Noise Density
Small-Signal Bandwidth
Low-Frequency Cutoff
Transimpedance Linear Range
Deterministic Jitter
Power-Supply Rejection Ratio
(PSRR)
-3dB, input
≤
20µA DC
Peak-to-peak, 0.95 < linearity < 1.05
(Note 3)
Output referred, f < 2MHz,
PSRR = -20log (∆V
OUT
/∆V
CC
)
40
14
50
50
SO package (Note 2)
(Note 2)
1515
Differential, measured with 40µAp-p signal
Single ended (per side)
Input = 1mAp-p
1470
47.7
155
1210
1.0
0.65
485
11.0
1900
24
2550
668
CONDITIONS
MIN
0.67
TYP
0.83
26
1900
50
250
1500
MAX
0.97
53.2
2355
52.1
430
1865
UNITS
V
mA
Ω
Ω
mVp-p
Ω
mAp-p
mA
nA
pA/(Hz)
1/2
MHz
kHz
µAp-p
ps
dB
MAX3266/MAX3267
Note 1:
Source Capacitance represents the total capacitance at the IN pin during characterization of noise and bandwidth parame-
ters. Figure 1 shows the typical source capacitance vs. reverse voltage for the photodiode used during characterization of
TO-56 header packages. Noise and bandwidth will be affected by the source capacitance. See the
Typical Operating
Characteristics
for more information.
Note 2:
Input-Referred Noise is calculated as RMS Output Noise / (Gain at f = 10MHz). Noise Density is (Input-Referred Noise) /
√bandwidth.
No external filters are used for the noise measurements.
Note 3:
Deterministic Jitter is measured with the K28.5 pattern applied to the input [00111110101100000101].
_______________________________________________________________________________________
3
1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise
Transimpedance Preamplifiers for LANs
MAX3266/MAX3267
Typical Operating Characteristics
(V
CC
= +3.3V, T
A
= +25°C, MAX3266/MAX3267 EV kit, source capacitance = 0.85pF, unless otherwise noted.)
MAX3266
INPUT-REFERRED NOISE vs. TEMPERATURE
MAX3266/67-01
MAX3267
INPUT-REFERRED NOISE vs. TEMPERATURE
MAX3266/67-02
FREQUENCY RESPONSE
MAX3266
70
TRANSIMPEDANCE (dB)
MAX3266/67-03
250
240
INPUT-REFERRED NOISE (nA)
230
220
210
200
190
180
170
0
INPUT-REFERRED NOISE (nA)
C
IN
IS SOURCE CAPACITANCE
PRESENTED TO DIE, INCLUDING
PACKAGE PARASITIC, PIN DIODE,
AND PARASITIC INTERCONNECT
CAPACITANCE.
650
600
550
500
450
400
350
C
IN
IS SOURCE CAPACITANCE
PRESENTED TO DIE, INCLUDING
PACKAGE PARASITIC, PIN DIODE,
AND PARASITIC INTERCONNECT
CAPACITANCE.
75
65
MAX3267
60
C
IN
= 1.0pF
C
IN
= 1.5pF
25
50
C
IN
= 0.5pF
C
IN =
1.5pF C
IN =
1.0pF
-50
-25
0
25
50
C
IN =
0.5pF
55
50
75
100
1M
10M
100M
FREQUENCY (Hz)
1G
10G
JUNCTION TEMPERATURE (°C)
75
100
JUNCTION TEMPERATURE (°C)
DETERMINISTIC JITTER
vs. INPUT AMPLITUDE
MAX3266/67-04
INPUT-REFERRED RMS NOISE CURRENT
vs. DC INPUT CURRENT
MAX3266/67-05
SMALL-SIGNAL TRANSIMPEDANCE
vs. TEMPERATURE
69
68
TRANSIMPEDANCE (dB)
67
66
65
64
63
62
MAX3267
MAX3266
MAX3266/67-06
100
90
PEAK-TO-PEAK JITTER (ps)
80
70
60
50
40
30
20
10
0
10
MAX3266
100
PEAK-TO-PEAK AMPLITUDE (µA)
MAX3267
1000
900
INPUT-REFERRED NOISE (nA)
800
700
600
500
400
300
200
100
0
MAX3266
1
10
100
MAX3267
70
61
1000
60
-50
-25
0
25
50
75
100
AMBIENT TEMPERATURE (°C)
1000
DIFFERENTIAL DC INPUT CURRENT (µA)
MAX3266
BANDWIDTH vs. TEMPERATURE
MAX3266/67-07
MAX3267
BANDWIDTH vs. TEMPERATURE
MAX3266/67-08
OUTPUT AMPLITUDE vs. TEMPERATURE
MAX3266/67-09
1090
1040
BANDWIDTH (MHz)
990
940
BANDWIDTH (MHz)
AMPLITUDE (mV)
100
C
IN
IS SOURCE CAPACITANCE
PRESENTED TO DIE, INCLUDING
PACKAGE PARASITIC, PIN DIODE,
AND PARASITIC INTERCONNECT
CAPACITANCE.
2400
350
300
250
200
150
100
50
0
-50
-25
0
25
50
75
C
IN
IS SOURCE CAPACITANCE
2300 PRESENTED TO DIE, INCLUDING
PACKAGE PARASITIC, PIN DIODE,
2200 AND PARASITIC INTERCONNECT
CAPACITANCE.
2100
C
IN =
0.5pF
2000
1900
1800
1700
C
IN =
1.0pF
C
IN =
1.5pF
-25
0
25
50
75
JUNCTION TEMPERATURE (°C)
C
IN
= 0.5pF
890
840
790
740
0
25
50
75
100
JUNCTION TEMPERATURE (°C)
C
IN
= 1.0pF
C
IN
= 1.5pF
1600
1500
-50
100
AMBIENT TEMPERATURE (°C)
4
_______________________________________________________________________________________
1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise
Transimpedance Preamplifiers for LANs
MAX3266/MAX3267
Typical Operating Characteristics (continued)
(V
CC
= +3.3V, T
A
= +25°C, MAX3266/MAX3267 EV kit, source capacitance = 0.85pF, unless otherwise noted.)
EYE DIAGRAM (INPUT = 10µAp-p)
MAX3266/67-10
EYE DIAGRAM (INPUT = 1mAp-p)
MAX3266/67-11
EYE DIAGRAM (INPUT = 20µAp-p)
INPUT: 2
7
-1 PRBS
MAX3266/67-12
4mV/div
30mV/div
5mV/div
INPUT: 2
7
-1 PRBS
160ps/div
INPUT: 2
7
-1 PRBS
160ps/div
80ps/div
EYE DIAGRAM (INPUT = 1mAp-p)
INPUT: 2
7
-1 PRBS
MAX3266/67-13
DC TRANSFER FUNCTION
MAX3266/67-14
150
100
OUTPUT VOLTAGE (mVp-p)
50
MAX3266
0
-50
-100
-150
MAX3267
30mV/div
80ps/div
-200 -150 -100 -50
0
50
100 150 200
INPUT CURRENT (µA)
Pin Description
PIN
1
2
3
4
5
6
7
8
NAME
V
CC
N.C.
IN
FILTER
GND
OUT-
OUT+
GND
Supply Voltage
No Connection. Not internally connected.
Amplifier Input
Provides bias voltage for the photodiode through a 1.5kΩ resistor to V
CC
. When grounded, this pin disables
the DC Cancellation Amplifier to allow a DC path from IN to OUT+ and OUT- for testing.
Ground
Inverting Output. Current flowing into IN causes V
OUT-
to decrease.
Noninverting Output. Current flowing into IN causes V
OUT+
to increase.
Ground
FUNCTION
_______________________________________________________________________________________
5