DESCRIPTION

Omniyig offers both Pin Limiters and Schottky Turn-on Pin Limiters from .1 to 8 GHz. These limiters are designed for octave band performance, although their multi-octave performance is excellent. The PL2DI and SL2DI are 1 to 2 GHz units with SMA connectors, but work very well from .5 to 4 GHz.

Omniyig limiters are optimized for low insertion loss and VSWR at <= 0 dBm. At and above the turn-on point (+5 to +10 dBm) these limiters act as variable shunt R.F. impedances and are therefore reflective.

All of these units are available with SMA connectors or as cylindrical modules for stripline and ministrip applications. They are fabricated from semiconductor chips using high temperature dieattach and thermocompression bonding techniques. The modules are hermetically sealed.

1)PIN diode Microwave Limiter

DESCRIPTION

Omniyig‘s PIN diode limiters are designed for octave-band performance, although their multi-octave performance is excellent. The OLP2644A is an 8.0 to 16.0 GHz unit with SMA connectors. This limiter performs very well from 6.0 to 18.0 GHz. The OLP2716 is designed to operate from 1.0 to 2.0 GHz, but performs very well from 0.5 to 4.0 GHz.

Omniyig‘s limiters are optimized for low insertion loss and VSWR at < 0 dBm. At and above the turn-on point (+5 to +10 dBm), these limiters act as variables shunt R.F. impedances and they are reflective.

All of these limiters are available with SMA connectors, or cylindrical, or rectangular modules for stripline and ministrip applications, without d.c. returns. Units may be supplied with or without other connector configurations as specials.

Omniyig fabricates these units utilizing semiconductor chips high temperature die attach and thermocompression bonding technique. All units are in hermetic modules.
 
FEATURES

Lowest insertion loss

Low VSWR.

Medium power (100 Watts
Peak, 2 Watts CW)

Fast recovery time.

Internal DC Return
(Most Models)

APPLICATIONS

The Omniyig limiters are generally used as protective devices. They protect sensitive devices such as tunnel diode amplifiers, mixers, detectors, and receivers from medium powers (100 watts peak, 2 watts C.W.) which might damage them.

These limiters have other applications such as contouring frequency response and keeping input amplitudes to amplifiers at lower level. This will keep them out of undesirable overdrive output characteristics.

Limiters of this type, without d.c. returns, have been used as switches at lower level signals to modulate signals. With the proper logic circuits, external d.c. returns are applied during high power conditions allowing normal limiter operation.

 
2)Schottky Turn-On MICROWAVE LIMITERS
DESCRIPTION

Omniyig‘s Schottky turn-on limiters are designed for octave-band performance, although their multi-octave performance is excellent. The OLP2644A is an 8.0 to 16.0 GHz unit with SMA connectors. This limiter performs quite well from 2.0 to 18.0 GHz and extremely well from 4.0 to 18.0 GHz. In the 2.0 to 4.0 GHz frequency range, this unit‘s insertion loss may increase slightly due to Ku-band d.c. blocks and the leakage power will rise slightly due to X-Ku-band diode spacing. The OLP2716A is a 1.0 to 2.0 GHz unit with SMA connectors. This limiter performs quite well from 0.5 to 6.0 GHz. There are models which are optimized for any octave from 0.1 to 18.0 GHz. All limiters are available with SMA connectors, or cylindrical module, or rectangular module for stripline or microstrip applications. Limiters are normally supplied with internal d.c. block, but can be supplied with one or both d.c. blocks eliminated. Limiters may be supplied with other connector options as specials.

The Omniyig Schottky turn-on limiters are optimized for low insertion loss and VSWR at <= 0 dBm. At and above the turn-on point (+5 to +10 dBm), these limiters operate as variable shunt R.F. impedances and are therefore reflective.

These limiters are fabricated from semiconductor chips utilizing high temperature die attach and thermocompression bonding techniques. The limiters are hermetically sealed.

APPLICATIONS

Omniyig limiters are designed to be used in a number of applications. The first and most common is to protect from burn-out during high CW power (up to 10 watts) and medium high peak power (up to 1 KW). These types of limiters have been put in front of tunnel diode amplifiers, detectors, mixers, and other sensitive microwave components or receivers.

Another application for this type of limiter is to shape frequency response of the output of microwave sources such as leveling a Gunn oscillator or transistor oscillator. This is accomplished simply by screwing on to the output. Because of the reflective nature of these limiters, they may be integrated with a ferrite to give a good source match. This integration can be implemented at Omniyig as a special, such that size can be minimized and performance optimized.

These limiters have been used on the input of traveling-wave tube amplifiers to keep the TWTA from going into overdrive when large signals are applied to the amplifier input. This same application applies in TWTA chains using one of these limiters between the amplifiers in teh chain so that the input amplifier cannot overdrive the output amplifier.
 

FEATURES

Lowest insertion loss

High CW Power Handling

Low Leakage

Medium High Peak Power
Handling

Compact Size

Octave or Broadband
Optimization Available

Hermetic Package

Reduced Spike Leakage Over
Conventional Pin Limiters

SPECIALS & PERFORMANCE NOTES

The recovery time associated with this Series of limiter is in the range of 200 to 500 nanoseconds. The recovery time may be reducedto 50 to 100 nanoseconds by adding a discharge path speed-up resistor. By choosing the proper resistance value, this only raises the leakage power a few tenths of a dB. The speed-up resistor can also be tailored to raise the turn-on point (1 dB compression). The normal turn-on is approximately +5 to +10 dBm. This can be raised to +20 dBm or any point in between. The maximum leakage also increases.

The limiters may be used as switch/limiter by eliminating one of the d.c. blocks and applying bias on the center conductor. This will reverse bias the Schottky diode while forward biasing the PIN diodes. Since this bias level is usually one volt across the PIN diodes, there is no danger of harming the Schottky.

These limiters operate as reflective devices. In some uses, a good match is required for proper operation. Omniyig limiters can be integrated with an isolator on one or both ports.

The second PIN diode may be eliminated to improve insertion loss. This changes the leakage curves to be similar to the conventional PIN limiters. The leakage power is 3 dB or 4 dB lower than conventional PIN limiters. The power handling is lowered. These designs can be modified and diodes selected to handle 3 dB higher power.