Features • LVDS/CMOS Outputs • LVDS/CMOS/Crystal Clock Source with PLL Multiplication • Integrated Flexible Spread Spectrum Clock Generation • CDS or S/H Processing for CCD or CIS sensors • Independent Gain/Offset Correction for Each Channel • Automatic per-Channel Gain and Offset Calibration • Programmable Input Clamp Voltage • Flexible CCD/CIS Sensor Timing Generator Description The LM98725 is a fully integrated, high performance 16-Bit, 81 MSPS signal processing solution for digital color copiers, scanners, and other image processing applications. High-speed signal throughput is achieved with an innovative architecture utilizing Correlated Double Sampling (CDS), typically employed with CCD arrays, or Sample and Hold (S/H) inputs (for higher speed CCD or CMOS image sensors). The signal paths utilize 8 bit Programmable Gain Amplifiers (PGA), a +/-9-Bit offset correction DAC and independently controlled Digital Black Level correction loops for each input. The PGA and offset DAC are programmed independently allowing unique values of gain and offset for each of the three analog inputs. The signals are then routed to a 81MHz high performance analog-to-digital converter (ADC). The fully differential processing channel shows exceptional noise immunity, having a very low noise floor of -74dB. The 16-bit ADC has excellent dynamic performance making the LM98725 transparent in the image reproduction chain. A very flexible integrated Spread Spectrum Clock Generation (SSCG) modulator is included to assist with EM compliance and reduce system costs. Key Specification Maximum Input Level 1.2 or 2.4 Volt Modes (both with + or - polarity option) ADC Resolution 16-Bit ADC Sampling Rate 81 MSPS INL +17/- 28 LSB (typ) Channel Sampling Rate 30/30/27 MSPS PGA Gain Steps 256 Steps PGA Gain Range 0.62 to 8.3x Analog DAC Resolution +/-9 Bits Analog DAC Range +/-307mV or +/-614mV Digital DAC Resolution +/-6 Bits Digital DAC Range -2048 LSB to + 2016 LSB SNR -74dB (@0dB PGA Gain) Power Dissipation 755mW (LVDS) Operating Temp 0 to 70°C Supply Voltage 3.3V Nominal (3.0V to 3.6V range) Applications • Multi-Function Peripherals • High-speed Currency/Check Scanners • Flatbed or Handheld Color Scanners • High-speed Document Scanners

Also Recommended LM98519▲ For A 6-channel AFE, With CMOS Outputs LM98620▲ For A 6-channel AFE, With LVDS Outputs LM98714▲ For A Lower-Speed Part With Fewer Features Typical Application MY BRIEFCASE                                       Click any "Briefcase" icon to add an item

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Datasheet

Title		Size	Date	Other Language
	LM98725 3 Channel, 16-Bit, 81 MSPS Analog Front End with LVDS/CMOS Output, Integrated CCD/CIS Sensor Timing Generator and Spread Spectrum Clock Generation	464 Kbytes	24-Sep-09

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Title		Size	Date	Other Language
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