VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
3.125Gb/s Integrated Transimpedance
and Limiting Amplifier with Signal Detect
VSC7969
Electrical Characteristics
Table 1: AC Specifications
Symbol
Parameter
Min
Typ
Max Units
Conditions
Peak-to-peak AC current
amplitude
∆IPH
Input Photocurrent Swing
2.2
mA
µA
-23dBm average optical power
with a detector responsitivity of
0.8A/W.
IPHS-AVG
Average Photocurrent Sensitivity
Peak Input Photocurrent Sensitivity
4
8
-23dBm average optical power
with a detector responsitivity of
0.8A/W.
IPHS-PEAK
µA
Single-Ended Output Voltage
Amplitude
Single-ended peak-to-peak
measurement, IIN >20µA.
∆VOUT-SE
∆VOUT-DIFF
tR, tF
200
250
500
300
600
mV
mV
Differential peak-to-peak
measurement, IIN >20µA.
Differential Output Voltage Amplitude 400
Rise and Fall Time
At 2.2mAp-p input photocurrent
swing. 20% to 80%.
60
27k
1
100
40k
ps
Ω
(1)
ZT
Transimpedance Gain
20k
Differential measurement
Modulation frequency between FL
and BW
(1)
∆ZT
Ripple in Passband Transimpedance
dB
Referenced to 10MHz,
CPD = 0.6pF
BW
FL
Upper -3dB Bandwidth
2.2
2.5
3.0
GHz
Referenced to 10MHz, CPD =
0.6pF with no external
components
Lower -3dB Cutoff Frequency
100
kHz
ZO
Output Impedance
50
TBD
500
0.6
2
Ω
Single-ended
PSRR
INOISE
CPD
Power Supply Rejection Ratio
Input-Referred rms Noise Current
Photodetector Capacitance
Signal Detect Hysterisis
nA
pF
dB
30kHz to 2.5GHz
0.4
1
0.8
4
Bias voltage on detector at 2.0V
Electrical measurement on SD pin
SDH
Average photocurrent with SD
open.
SDA-OPEN
SDD-OPEN
SDA-SHORT
SDD-SHORT
Signal Detect Assertion Level
Signal Detect Deasseration Level
Signal Detect Asseration Level
Signal Detect Deasseration Level
3
5
9
µA
µA
µA
µA
Average photocurrent with SD
open.
1.0
6
2.2
10
4.4
3.0
18
6.0
Average photocurrent with SD
shorted to ground.
Average photocurrent with SD
shorted to ground.
2.0
VCCS
- 0.3
SDHIGH
SDLOW
Signal Detect HIGH Logic Level
Signal Detect LOW Logic Level
V
V
0.5
0.8
© 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 2
G52355-0, Rev 2.0
02/09/01