Which is healthier, an energetic crystal oscillator or a passive crystal oscillator?

Within the crystal industry, we call crystals as passive crystals, crystal oscillators are called energetic crystal oscillators, passive crystals are frequently called quartz resonators, energetic crystal oscillators are called quartz oscillators, these two products utilized in electronic products corresponding to telecommunication equipment and satellites. Hardware products as reference signals and satellites. More stable time or frequency control. In recent times, crystal oscillator terminal technology has rapidly developed in clock modules, satellite communications, image processing, base station navigation, and particularly the clock module industry.

1. What’s an energetic crystal oscillator

The energetic crystal oscillator (oscillator) has 4 pins and is a whole oscillator. Along with the quartz crystal, there are transistors and resistive-capacitive elements. Due to this fact, it’s large in size and only needs an influence supply to acquire a greater waveform. The energetic crystal oscillator package has 4 pins that are VCC (voltage), GND (ground), OUT (clock signal output) and NC (empty pin). A well-liked point of the energetic crystal oscillator is the direct connection of the quartz wafer and the clock oscillator IC. The best effect may be achieved by controlling the voltage of the crystal oscillator itself, which may be matched to an external capacitor without causing a frequency shift.

Many engineers will encounter such problems within the product design process: First, the matching of the crystal oscillator within the circuit just isn’t perfect, which affects the use effect; Secondly, the temperature drift of the crystal oscillator is simply too large and even affects the product performance.

Nowadays, modernization of electronic products is especially common. Cost have to be a very important factor taken under consideration by the manufacturer. Using a crystal oscillator also takes cost under consideration. Due to this fact, when engineers design circuits, the value of crystal oscillators (energetic crystal oscillators) is 5-10 times higher than strange passive crystals, which results in more. The circuit uses passive crystal oscillators; just some high-end products corresponding to industrial control products and high-speed communication products prefer energetic crystal oscillators, which is why the above-mentioned common problems occur. The rationale is that the performance of a passive crystal oscillator depends not only on the index of the crystal oscillator itself, but additionally on the matching of the oscillator circuit design.

Energetic crystal oscillators wouldn’t have to fret about this problem because many passive crystal oscillators can’t be matched on account of external capacitors. The energetic crystal oscillator has a voltage control function and might robotically adjust the external capacitance through the inner IC board. The second point is the excessive temperature drift of the crystal oscillator, commonly referred to as temperature drift. This phenomenon could be very deadly. If the product is in normal working condition, the frequency drift attributable to temperature change suddenly becomes too large, the product will seriously stop working and be damaged. The passive crystal itself is a crystal plate and has no temperature compensation function. There may be a temperature compensated crystal within the energetic crystal.

The energetic crystal oscillator doesn’t need the inner oscillator of the processor, the signal is stable, the standard is healthier, and the connection method is comparatively easy (mainly good at power filtering, capacitor and inductor are frequently used for this) form a filter network, and the output end is filtered by a low resistance resistor. signal is sufficient), no complicated configuration circuit is required.

2. What’s a passive crystal oscillator

Passive crystal oscillator generally refers to a quartz resonator, quartz resonator (English: quartz crystal unit or quartz resonator, often denoted as Xtal, Extenal Crystal Oscillator, external crystal oscillator, since the crystal unit is commonly used as an external circuit), known as quartz crystal or quartz oscillator is an electronic component that uses the piezoelectric effect of a quartz crystal (also referred to as a crystal) to generate high-precision oscillation frequencies and is a passive component. The component is especially composed of quartz plate, base, shell, silver glue, silver and other ingredients. As a consequence of the state of the pins, they may be divided into two types: in-line (with pins) and surface-mount (without wires). Currently, the primary commonly used packaging types are HC-49U, HC-49/S, GLASS, UM-1, UM-4, UM-5 and SMD.

The passive crystal oscillator is a non-polar component with 2 pins. To generate an oscillating signal, it needs the assistance of a clock circuit and can’t oscillate itself. Passive crystal oscillators have poor signal quality and frequently require precise matching of peripheral circuitry (capacitors, inductances, resistances to match the signal, etc.). When replacing crystals with different frequencies, the peripheral configuration circuitry must even be adjusted accordingly. It is mostly advisable to make use of high-precision quartz crystals and, if possible, not to make use of low-precision ceramic crystals.

3. Difference between energetic crystal oscillator and passive crystal oscillator

Signal quality 3.1

Energetic crystal oscillator doesn’t require internal DSP oscillator, the signal quality is sweet, relatively stable, and the connection method is comparatively easy (mainly for good power filtering, often a PI type filter network composed of a capacitor and an inductor and a small resistor on the output (the resistance value can filter the signal) and no complex configuration circuit is required. Passive crystal oscillators must use the built-in DSP oscillator. Passive crystal oscillators haven’t any voltage problems, and the signal level is variable, that’s, it is ready in keeping with the oscillator circuit.

The identical crystal may be used for various voltages and may be used in numerous DSPs with different clock signal voltage requirements. Due to this fact, for general applications, if conditions allow, it’s endorsed to make use of crystal. This is very useful for manufacturers with multiple product lines and huge volumes. The standard approach to connecting an energetic crystal oscillator: one pin is suspended, two pins are grounded, three pins are connected to the output, and 4 pins are connected to the voltage. In comparison with passive crystals, the drawback of energetic crystals is that their signal level is fixed and an appropriate output level have to be chosen, which is less flexible. It’s endorsed to make use of precision quartz crystals and to avoid using low precision ceramics at any time when possible.

3.2 Price

Energetic crystal oscillators are costlier, however the energetic crystal oscillator itself can vibrate. Whether it’s a passive crystal oscillator or an energetic crystal oscillator, it has its benefits and drawbacks. If the fee of the product is taken under consideration, it’s endorsed to decide on a passive crystal oscillator circuit; If product performance is taken into account, it’s endorsed to decide on energetic crystal oscillator circuit, which saves time and convenience. It may well guarantee the product performance.

accuracy 3.3

The very best accuracy of the passive crystal oscillator is 5 ppm, while the accuracy of the energetic crystal oscillator can reach 0.1 ppm. The upper the accuracy, the higher the frequency stability. The energetic crystal oscillator is healthier than the passive crystal oscillator by way of stability, nevertheless it also has its small disadvantages. The signal level of an energetic crystal oscillator is fixed, so you will need to select an appropriate output level that’s less flexible.

3.4 Time requirements

Personally, I feel that for time-sensitive applications, an energetic crystal is healthier because you may select a more precise crystal or perhaps a high-end temperature-compensating crystal. Some DSPs haven’t any internal oscillator circuit and will only use energetic crystal oscillators, corresponding to TI’s 6000 series. Compared with passive crystals, energetic crystals often have a bigger volume, but nowadays many energetic crystals are surface-mounted, and the amount is reminiscent of the crystals, and a few are even smaller than many crystals.

3.5 Shape

Energetic crystal oscillators typically have 4 contacts, one power supply, one ground, one signal output and one NC (empty contact). The one marked with a dot is pin 1, and the counterclockwise (down pin) is 2, 3 and 4 respectively. A passive crystal oscillator has 2 pins and wishes the assistance of an external clock circuit (connected to the oscillation circuit contained in the primary IC) to generate an oscillating signal and can’t oscillate itself.

3.6 Voltage and cargo

An energetic crystal oscillator has a no-load voltage and a passive crystal oscillator has a no-load voltage. (Summarized by Easyboom)