F0100406B

3.3V 1.25Gbit/s Transimpedance Amplifier

General Description

A transimpedance amplifier is applied as a pre-amplifier which is an amplifier for a faint photo

current from a PIN photo diode (PD). The performance in terms of sensitivity, bandwidth, and so

on, obtained by this transimpedance amplifier strongly depend on the capacitance brought at the

input terminal; therefore, “typical”, “minimum”, or “maximum” parameter descriptions can not

always be achieved according to the employed PD and package, the assembling design, and

other technical experts. This is the major reason that there is no product lineup of packaged

transimpedance amplifiers.

Thus, for optimum performance of the transimpedance amplifier, it is essential for customers to

design the input capacitance carefully.

Hardness to electro-magnetic interference and fluctuation of a power supply voltage is also an

important point of the design, because very faint photo-current floes into the transimpedance

amplifier. Therefore, in the assembly design of the interconnection between a PD and a

transimpedance, noise should be taken into consideration.

Recommendation

SEI basically recommends The F08 series PD preamplifier modules for customers of the

transimpedance amplifiers. In these modules, a transimpedace amplifier, a PD, and a noise filter

circuit are mounted on a TO-18-can package hermetically sealed by a lens cap, having typically

a fiber pigtail. The F08series lineups are the best choice for customers to using the F01series

transimpedance amplifiers. SEI’s F08 series allows the customers to resolve troublesome design

issues and to shorten the development lead time.

Noise Performance

F0100406B based on GaAs MES FET’s shows excellent low-noise characteristics compared

with IC’s based on the silicon bipolar process. Many transmission systems often demand

superior signal-to –noise ratio, that is, high sensitivity; F0100406B is the best Choice for such

applications.

The differential circuit configuration in the output enable a complete differential operation to

reduce common mode noise: simple single ended output operation is also available.

Die-Chip Description

F0100406B is shipped like the die-chip described above. The die thickness is typically 280um

±

20um with the available pad size uncovered by a passivation film of 95um square.The material of

the pads is TiW/Pt/Au and the backside is metalized by Ti/Au.