SiTime oscillator enhance performance in industrial camera-YQM Electronis

Industrial cameras are a crucial element of machine vision systems. Typical applications include automatic imaging-based inspection, process control, robot guidance, surveillance, microscopy, motion analysis, mapping, document digitizing, as well as medical imaging. Data collected by cameras are usually processed by a computer, with or without artificial intelligence.

Camera systems are based on a CMOS imager, a processing SoC or FPGA, and interfaces to transfer images to the "outside world." Depending on the application, imagers of different resolutions and frame rates are chosen. CMOS image sensors exist in different sizes. In general, the larger the sensor size, the better the dynamic range and signal-to-noise (SNR) ratio.

An SoC or FPGA processes the data collected by the image sensor. Typical processing includes creating usable still images or a video stream from the raw sensor data and compressing them for transmission. More advanced processing such as pattern recognition can be performed either in-camera, or in a central computer.

Various interfaces to connect cameras to other elements of a machine vision system exist. The most common are Ethernet, USB, GMSL (Analog Devices), V3-Link and FPD-Link (Texas Instruments). Wi-Fi or proprietary wireless interfaces can also be used.

Typical CMOS imagers require a fixed frequency clock between 6 MHz and 72 MHz. As a general rule, the higher the sensor data rate, the higher the clock frequency. The data rate mainly depends on three characteristics:

Resolution, related to sensor size (ranging from 5 x 4 mm to 54 x 40 mm) and pixel pitch
Frames per second
Bits per pixel

As digital devices, SoCs and FPGAs can be easily clocked with a single-ended oscillator in the 10 to 40 MHz range such as the SiT1603. An optional 32.768 kHz oscillator can be added if real-time-clock timekeeping is needed. A low-power oscillator such as the SiT1811, consuming only 6 μA, enables accurate time keeping in standby mode.

Interface clocking depends on the chipset; in general:

Ethernet with a single-ended 25 MHz
USB with a single-ended 48 MHz or a differential 100 MHz
GMSL with a single-ended clock with frequency such as 25 MHz
V3-Link and FPD-Link with a single-ended frequency in the range of 25 MHz to 100 MHz

Type	Prodcuct	Frequency	Key Features	Key Values
MHz oscillator	SIT8008	1 to 110 MHz	• -40°C to +85°C • ±20 ppm stability • 5 std package sizes	• High reliability • Flexible frequency options • Excellent stability over temperature
	SIT8021	1 to 26 MHz	• -40°C to +85°C • ±50 ppm stability • 1.5 x 0.8 CSP package	• High reliability • Extended temperature range • Small footprint • Wide programmable freq range
Differential oscillator	SIT9366	1 to 220 MHz	• Low jitter 0.23 ps RMS1 • LVPECL, LVDS, HCSL • 2.5 to 3.3 V • -40°C to 105°C • 3.2 x 2.5 mm package	• High reliability • Low power • Various standard package options
32.768 kHz oscillator	SIT1811	32.768 kHz	• ±20, ±50 ppm stability • 1.14 to 3.3 V supply • typ. 490 nA current consumption (no load) • Up to -40°C to +105°C • 1.2 x 1.1 mm QFN	• Meets demanding jitter requirements • Small PCB footprint, easier layout • Easy design due to flexibility • MEMS reliability
32.768 kHz TCXO	SIT1552	32.768 kHz	• ±5, ±10, ±20 ppm stability • 1 µA current consumption • Up to -40°C to +85°C • 1.5 x 0.8 CSP package	• Low power • Small footprint • Excellent stability enables better time keeping over longer periods of standby time, thus saving even more power

Resolution, related to sensor size (ranging from 5 x 4 mm to 54 x 40 mm) and pixel pitch
Frames per second
Bits per pixel

Interface clocking depends on the chipset; in general:

Ethernet with a single-ended 25 MHz
USB with a single-ended 48 MHz or a differential 100 MHz
GMSL with a single-ended clock with frequency such as 25 MHz
V3-Link and FPD-Link with a single-ended frequency in the range of 25 MHz to 100 MHz

Type	Prodcuct	Frequency	Key Features	Key Values
MHz oscillator	SIT8008	1 to 110 MHz	• -40°C to +85°C • ±20 ppm stability • 5 std package sizes	• High reliability • Flexible frequency options • Excellent stability over temperature
	SIT8021	1 to 26 MHz	• -40°C to +85°C • ±50 ppm stability • 1.5 x 0.8 CSP package	• High reliability • Extended temperature range • Small footprint • Wide programmable freq range
Differential oscillator	SIT9366	1 to 220 MHz	• Low jitter 0.23 ps RMS1 • LVPECL, LVDS, HCSL • 2.5 to 3.3 V • -40°C to 105°C • 3.2 x 2.5 mm package	• High reliability • Low power • Various standard package options
32.768 kHz oscillator	SIT1811	32.768 kHz	• ±20, ±50 ppm stability • 1.14 to 3.3 V supply • typ. 490 nA current consumption (no load) • Up to -40°C to +105°C • 1.2 x 1.1 mm QFN	• Meets demanding jitter requirements • Small PCB footprint, easier layout • Easy design due to flexibility • MEMS reliability
32.768 kHz TCXO	SIT1552	32.768 kHz	• ±5, ±10, ±20 ppm stability • 1 µA current consumption • Up to -40°C to +85°C • 1.5 x 0.8 CSP package	• Low power • Small footprint • Excellent stability enables better time keeping over longer periods of standby time, thus saving even more power

SiTime oscillator enhance performance in industrial camera

SiTime oscillator enhance performance in industrial camera

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