Euvis

10 Gbps Transimpedance Amplifier, TA205C

10 Gbps Transimpedance Amplifier
TA205CPRODUCT DESCRIPTION
TA205C is a high gain transimpedance amplifier optimized for 10Gb/s fiber optic
communication systems such as 10 Gigabit Ethernet, SONET OC-192 and SDH STM-64.
Compared to TA205B, TA205C operates across a wider temperature range. The
transimpedance amplifier consists mainly of a transimpedance stage, a differential gainstage, and a differential 50 Ω output driver. An internal DC-control circuit is included tomaintain proper data crossover points. Due to high gain of the amplifier, a differential
output of 100mVp-p or larger is available with input current larger than 10uAp-p,eliminating the need of a separate post-amplifier in most applications. The amplifier isavailable in die form and can be integrated with PIN or APD photodetector to function as
an optical receiver in 10 Gbps systems.

KEY FEATURES• 10 kΩ (80 dBΩ) differential transimpedance gain
• 9 GHz Bandwidth• Typical noise current density: 10 pA/rt Hz• Internal circuitry for maintaining data crossover points• <30 kHz low cutoff frequency• Input bias: +2.6 V• Current consumption: 48 mA• Power supply: +5.0 V• Die size: 1.4 mm x 1.1 mm

BLOCK DIAGRAM

InDriverVrefVsvo

OUTP
OUTN

servo

1
TA205C_DS_A4

Euvis

10 Gbps Transimpedance Amplifier, TA205C

ELECTRICAL SPECIFICATIONSPhotodiode and bond wire reference model Cpd=0.2 pF and Lpd=0.7 nH

Parameter

SymbolMin

TypicalMax

Unit

Ambient Temperature

To

-40

2585oDifferential Transimpedance

Zt

7,000

10,00012,000Ω

Input Noise Current Density1Inoise

Upper -3dB BandwidthBW

8910GHz

Low Frequency -3dB Cutoff4

BWLF

1030100kHz

Maximum Output Swing2Vout

250300350mVpp

Group Delay Variation1

∆GD

30ps

Input Overload Current3IOL

2mAOutput Impedance

ZOUT

Minimum Output Return Loss1

RL

Current Consumption

IPS

104550pA/rtHz

55

104248CΩdB

55

mA

150 MHz to 10 GHz
single-ended
3for BER=1x10-12; 231-1 PRBS @ 10Gb/s
4560pF external capacitor to pads Vsvo & Vref
22TA205C_DS_A4

Euvis

10 Gbps Transimpedance Amplifier, TA205C

PAD DESCRIPTIONName

Function

I/O

SignalVCCIPower supply (input), +5.0 V

PS

DC

VCC

Power supply, +5.0 V

PS

DC

GND

GroundRF input, connected to anode of photodiodeNon-inverted Output
Inverted Output
Reference voltage output
Reference voltage input
Photodiode bias voltage
Filter resistor output, connected to cathodeof photodiode

GND

DC

I
O
O
O
I
PS
O

RFIN
OUTP
OUTN
VSVO
VREF
VPD
FIL

RF
RF
DC
DC
DC
DC

BOND PAD ARRANGEMENTS

40 10040 12040 100

GND

OUTP

GND

OUTN

40410

40 100

410

GND

40
VSVO
VCCI
VREF

VPD2602701090±3030 120 30 120 30

VCC

270

GND

GND
GND

IN

GND

FIL

56040 100 40
1390±30420

40 100100 40 100 40410• Die Size: 1390±30 µm x 1090±30 µm• Die thickness: 7mil

Unit: µm

3
TA205C_DS_A4

Euvis

10 Gbps Transimpedance Amplifier, TA205C

TYPICAL PERFORMANCE

Transimpedance (dB-ohm)

80
70
60
50
4030
20
1000.1

1.0

10.0

100.0

Frequency (GHz)

Typical transimpedance gain with reference PD and bond wire

Typical 10Gb/s single-ended output of PIN-TA205C (Pin=-14dBm)

4TA205C_DS_A4

Euvis

10 Gbps Transimpedance Amplifier, TA205C

APPLICATIONTo set the reference voltage (Vref) automatically and ensure proper low cutoff frequency,
an external capacitor of 560pF or larger is recommended. A reference voltage isestablished through the servo circuitry in a feedback loop to maintain proper output DC
offset voltage and data crossover points. Due to high internal gain of the amplifier,robust ground/power supplies, bond wire control, and electrical isolation between input
and output ports of the die are all of paramount importance to prevent signal degradation
or even oscillation. Please consult Euvis technical support for related issues.
Power Supply (Vcci/Vcc)

PD bias (Vpd)

500Ω

InDriver

Vref
Vsvo
560pF

OUTP
OUTN

Servo

BONDING REFERENCE
Bond wire inductance of 700pH is recommended for photodiode to TIA input connection;
300pH or less each of inductance is recommended for other bond wires.
300pH

GND

300pH

OUTP GND OUTN

GND

GND

VCC

VSVO
VCCI
560pF

to power supply

VREF
VPD
GND

GND

IN

GND

to PD bias

FIL

0.7nH
Anode
CathodePD

5
TA205C_DS_A4Euvis

10 Gbps Transimpedance Amplifier, TA205C

Ordering Information:
E-mail: sales@euvis.com
Tel: (805) 583-9888
Fax: (805) 583-9889

The information contained in this document is based on preliminary product test results.
Characteristic data and other specifications are subject to change without notice.
Customers are advised to confirm information in this advanced datasheet prior to using
this information or placing the order.
Euvis Inc. does not assume any liability arising from the application or use of any productor circuit described herein, neither does it convey any license under its patents or any
other rights.

6
TA205C_DS_A4