SBAS603 Data sheet

SBAS603B April 2013 – November 2020 ADS4449

PRODUCTION DATA

Package Options

Mechanical Data (Package|Pins)

ZCR|144
- MPBGA77A

Thermal pad, mechanical data (Package|Pins)

Orderable Information

12.1 Device Nomenclature

Analog Bandwidth

The analog input frequency at which the power of the fundamental is reduced by 3 dB with respect to the low-frequency value.

Aperture Delay

The delay in time between the rising edge of the input sampling clock and the actual time at which the sampling occurs. This delay is different across channels. The maximum variation is specified as an aperture delay variation (channel-to-channel).

Aperture Uncertainty (Jitter)

The sample-to-sample variation in aperture delay.

Clock Pulse Width and Duty Cycle

The duty cycle of a clock signal is the ratio of the time the clock signal remains at a logic high (clock pulse width) to the period of the clock signal. Duty cycle is typically expressed as a percentage. A perfect differential sine-wave clock results in a 50% duty cycle.

Maximum Conversion Rate

The maximum sampling rate at which specified operation is given. All parametric testing is performed at this sampling rate, unless otherwise noted.

Minimum Conversion Rate

The minimum sampling rate at which the ADC functions.

Differential Nonlinearity (DNL)

An ideal ADC exhibits code transitions at analog input values spaced exactly 1 LSB apart. DNL is the deviation of any single step from this ideal value, measured in units of LSBs.

Integral Nonlinearity (INL)

INL is the deviation of the ADC transfer function from a best-fit line determined by a least-squares curve fit of that transfer function, measured in units of LSBs.

Gain Error

Gain error is the deviation of the ADC actual input full-scale range from the ideal value. Gain error is given as a percentage of the ideal input full-scale range. Gain error has two components: error as a result of reference inaccuracy and error as a result of the channel. Both errors are specified independently as E_GREF and E_GCHAN.

To a first-order approximation, the total gain error of E_TOTAL is approximately E_GREF + E_GCHAN.

For example, if E_TOTAL = ±0.5%, the full-scale input varies from (1 – 0.5 / 100) × f_{S ideal} to (1 + 0.5 / 100) × f_{S ideal}.

Offset Error

Offset error is the difference, given in number of LSBs, between the ADC actual average idle channel output code and the ideal average idle channel output code. This quantity is often mapped into millivolts.

Temperature Drift

The temperature drift coefficient (with respect to gain error and offset error) specifies the change per degree Celsius of the parameter from T_MIN to T_MAX. The coefficient is calculated by dividing the maximum deviation of the parameter across the T_MIN to T_MAX range by the difference of T_MAX – T_MIN.

Signal-to-Noise Ratio (SNR)

SNR is the ratio of the power of the fundamental (P_S) to the noise floor power (P_N), excluding the power at dc and the first nine harmonics.

Equation 1.

SNR is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to full-scale) when the power of the fundamental is extrapolated to the converter full-scale range.

Signal-to-Noise and Distortion (SINAD)

SINAD is the ratio of the power of the fundamental (P_S) to the power of all other spectral components, including noise (P_N) and distortion (P_D) but excluding dc.

Equation 2.

SINAD is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to full-scale) when the power of the fundamental is extrapolated to the converter full-scale range.