Low Noise,12-Bit, 25Msps ADC

The LTC1745 is a 25Msps, sampling 12-bit A/D converter designed for digitizing high frequency, wide dynamic range signals. Pin selectable input ranges of ±1V and ±1.6V along with a resistor programmable mode allow the LTC1745’s input range to be optimized for a wide variety of applications.

The LTC1745 is perfect for demanding communications applications with AC performance that includes 72.5dB SNR and 91dB spurious free dynamic range. Ultralow jitter of 0.3psRMS allows undersampling with excellent noise performance. DC specs include ±1LSB INL maximum and ±0.75LSB DNL over temperature.

The digital interface is compatible with 5V, 3V and 2V logic systems. The ENC and ENC inputs may be driven differentially from PECL, GTL and other low swing logic families or from single-ended TTL or CMOS. The low noise, high gain ENC and ENC inputs may also be driven by a sinusoidal signal without degrading performance. A separate digital output power supply can be operated from 0.5V to 5V, making it easy to connect directly to low voltage DSPs or FIFOs.

The TSSOP package with a flow-through pinout simplifies the board layout.

Applications

* Telecommunications

* Medical Imaging

* Receivers

* Cellular Base Stations

* Spectrum Analysis

* Imaging Systems

* Sample Rate: 25Msps

* 72.5dB SNR and 96dB SFDR (3.2V Range)

* 71dB SNR and 96dB SFDR (2V Range)

* No Missing Codes

* Single 5V Supply

* Low Power Dissipation: 380mW

* Selectable Input Ranges: ±1V or ±1.6V

* 240MHz Full Power Bandwidth S/H

* Pin Compatible Family

* 25 Msps: LTC1746 (14-Bit), LTC1745 (12-Bit)

* 50 Msps: LTC1744 (14-Bit), LTC1743 (12-Bit)

* 65 Msps: LTC1742 (14-Bit), LTC1741 (12-Bit)

* 80 Msps: LTC1748 (14-Bit), LTC1747 (12-Bit)