Product Details
Fig. 1 Functional Block Diagram
The ASNT7114-KHM is a high-speed, temperature-stable, and broadband dual-channel track-and-hold amplifier (THA). It performs sampling of the input differential analog signal dp/dn using two pairs of internally-generated strobe signals s11/s12 and s21/s22, and delivers two independent step-like differential signals q1p/q1n and q2p/q2n to the output. It features an adjustable track period length controlled by two external voltages t11crl/t12crl and t21crl/t22crl that modify the states of internal delay lines, which allows for maximizing the length of the “hold” time.
The differential gain of the chip is approximately 0dB, which corresponds to a single-ended-to-differential gain of -6dB. The gain can be adjusted using the external control voltage gaincrl. The chip supports both AC-coupled, and DC-coupled inputs. In the DC-coupled mode, the input common-mode voltage must be equal to vcc for optimal performance of the chip. The input sampled data path includes an equalizer that increases the bandwidth of the chip. The level of equalization is controlled by the external voltage pkcrl. The power consumption, bandwidth, and extra peaking of the input path can be adjusted via the external voltage bwcrl.
The chip may be controlled through a 3-wire SPI interface via a GUI provided by ADSANTEC. The GUI features all of the above-mentioned external controls, as well as the independent adjustment of power consumption of each element, the ability to turn off either one or both sampling channels, and independent channel peaking and gain controls. The SPI is turned off by default. The part’s inputs and outputs support the CML-type logic interface with an on-chip 50Ohm termination to vcc and may be used differentially, AC/DC coupled, single-ended, or in any combination.