VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
VSC7709
Features
• High Bandwidth: 1100MHz
• Low Input Noise Equivalent Power: 0.5mW
• Single 3.3V Supply
• 1.25Gb/s Data Rate
• 75mm Optically Active Area (PIN diode)
• Integrated AGC
• Package: TO-46, TO-56, Bare Die
1.25Gb/s Photodetector/Transimpedance
Amplifier for Optical Communication
Applications
• Gigabit Ethernet Optical Receivers
• Fibre Channel Optical Receivers
• ATM Optical Receivers
• System Interconnect
• SONET/SDH
General Description
The VSC7709 integrated PIN Photodetector/Transimpedance Amplifier provides a highly integrated solu-
tion for converting 1300 nm light from a fiber optic communications channel into a differential output voltage.
The benefits of Vitesse Semiconductor’s Gallium Arsenide H-GaAs process are fully utilized to provide a very
high bandwidth and low noise amplifier. The PIN detector is 75
µ
m in diameter. The detector bias is supplied
internally eliminating the need for a separate bias connection. The sensitivity, duty cycle distortion and jitter
meet or exceed all Fibre Channel and Gigabit Ethernet application requirements. The VSC7709 is available in
flat-windowed or lensed packages. The transimpedance amplifier is also available in bare die form.
The use of a photodetector and transimpedance amplifier hybrid, reduces the input capacitance, resulting in
higher sensitivity and bandwidth and improved speed of response. These parts can easily be used in developing
Fibre Channel and Gigabit Ethernet electro-optic receivers for the 900nm-1600nm spectral range which exhibit
very high performance and ease of use.
Block Diagram
+3.3V
D0
D1
G52362-0, Rev 2.1
04/02/01
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
Page 1
VITESSE
SEMICONDUCTOR CORPORATION
1.25Gb/s Photodetector/Transimpedance
Amplifier for Optical Communication
Advance Product Information
VSC7709
Electrical Characteristics
Table 1: Electro-Optic Specifications
Symbol
λ
V
DD
I
S
PSRR
BW
f
C
R
D
T
Z
R
O
V
N
NEP
O
S
∆V
V
D
PDJ
DCD
T
R
/T
F
Wavelength
Power Supply Voltage
Power Supply Current
Power Supply Rejection Ratio
Optical Modulation Bandwidth
Low Frequency Cutoff
Differential Responsivity
Differential Transimpedance
Single-Ended Output Impedance
Output Noise Voltage
Input Noise Equivalent Optical Power
Sensitivity
Bias Offset Voltage
Differential Output Voltage
Pattern Dependent Jitter
Duty Cycle Distortion
Rise and Fall Times
0.25
60
5
400
0.5
-26
200
Parameter
Min
1270
3.0
Typ
Max
1355
3.6
Units
nm
V
mA
dB
MHz
MHz
mV/µW
Ω
Ω
Conditions
30
TBD
1000
2
2.5
2000
25
1.2
f = 0.3MHz to 40MHz. Hybrid
differential with external filter.
See
Measurements and
Applications
section
See
Measurements and
Applications
section
R
L
= 100Ω
(1)
R
L
= 100Ω
(2)
mV rms BW = 800MHz, P = 0mW
µW
rms BW = 800MHz, P = 0mW
dBm
mV
V
ps
%
ps
BER 10
-12
, B = 1250Mb/s
(3)
P = -3dBm
P = -3dBm, R = 100Ω
P = -3dBm, ±10% voltage
window
P = -3dBm
20% to 80%, P = -3dBm
NOTES: (1) Applicable to packaged parts with assembled 1300nm photodetector with responsivity = 0.8A/W. (2) Applicable to bare dice.
(3) By characterization. See Measurements and Application section.
Absolute Maximum Ratings
(1)
Power Supply Voltage (V
DD
)........................................................................................................................... +6V
Maximum Junction Temperature Range...................................................................................... -55°C to +125°C
Storage Temperature Range......................................................................................................... -55°C to +125°C
Incident Optical Power (P
INC
) .................................................................................................................... +3dBm
NOTE: (1) CAUTION: Stresses listed under “Absolute Maximum Ratings” may be applied to devices one at a time without caus-
ing permanent damage. Functionality at or above the values listed is not implied. Exposure to these values for extended
periods may affect device reliability.
Recommended Operating Conditions
Positive Voltage Rail (V
DD
).................................................................................................................. 3.0 to 3.6V
Negative Voltage Rail (GND)............................................................................................................................ 0V
Operating Temperature Range (T
A
) ...........................................................................0°C Ambient to +85°C Case
Page 2
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
G52362-0, Rev 2.1
04/02/01
VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
VSC7709
Package Descriptions
1.25Gb/s Photodetector/Transimpedance
Amplifier for Optical Communication
Figure 1: Pin Diagram
TO Package
BottomView
VSS
DOUTP
DOUTN
GND
Table 2: Pin Identification for TO-46 (ball lens) and Bare Die
Symbol
D
+
OUT
D
–
OUT
VDD
GND
Description
Data output normal (with reference to incident light)
Data output complement (inverting, with reference to incident light)
Power supply
Ground (package case)
G52362-0, Rev 2.1
04/02/01
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
Page 3
VITESSE
SEMICONDUCTOR CORPORATION
1.25Gb/s Photodetector/Transimpedance
Amplifier for Optical Communication
Advance Product Information
VSC7709
Figure 2: Pad Assignments
961
µm
(37.8mil)
861
µm
(33.9mil)
Pad 3
CLOP
(A)
Pad 4
CLON
(A)
Pad 2
VGND
(A)
Pad 5
VGND
(A)
(A)
(A)
(A)
Pad 10
ANODE
MINUS
Bond Pad
Pad 9
ANODE
MINUS
Pad 8
CATHODE
<Probe Pads>
PLUS
1898
µm
(74.7mil)
1798
µm
(70.8mil)
(B)
(B)
Pad 1
VGND
Pad 6
VDD
Die Size:
Actual Die Size:
Die Thickness:
Pad Size (A):
Pad Passivation Opening (A):
861µm x 1798µm (33.9mil x 70.8mil)
961µm x 1898µm (37.8mil x 74.7mil)
254µm (10mil)
110µm x 110µm (4.3mil x 4.3mil)
86µm x 86µm (3.3mil x 3.3mil)
Pad Size (B):
220µm x 110µm (8.6mil x 4.3mil)
Pad Passivation Opening (B): 196µm x 86µm (7.7mil x 3.3mil)
Page 4
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
G52362-0, Rev 2.1
04/02/01
VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
VSC7709
Table 3: Pad Coordinates
Signal
Name
VGND
VGND
CLOP
CLON
VGND
VDD
CATHODE/PLUS
CATHODE/PLUS
ANODE/MINUS
ANODE/MINUS
1.25Gb/s Photodetector/Transimpedance
Amplifier for Optical Communication
Pad
Number
1
2
3
4
5
6
7
8
9
10
Coordinates (µm)
Description
X
110.00
55.00
55.00
806.00
806.00
751.00
482.50
576.50
301.50
181.50
Y
55.00
1582.40
1742.70
1742.70
1582.40
55.00
530.50
999.50
999.50
999.50
Ground
Ground
Data Output, True (with reference to incident light)
Data Output, Complement (inverting, with reference to
incident light)
Ground
Power Supply
Photodetector Cathode Connection
Photodetector Cathode Connection
Photodetector Anode Connection
Photodetector Anode Connection
G52362-0, Rev 2.1
04/02/01
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
Page 5
