DC1241B-BA Linear Technology, DC1241B-BA Datasheet - Page 17

• Manufacturer Part Number: DC1241B-BA
• Description: BOARD EVAL LTM9001-BA
• Manufacturer: Linear Technology
• Type: Baseband Receiverr

Specifications of DC1241B-BA

• Design Resources: DC1241B Schematic
• Frequency: 0Hz ~ 300MHz
• Features: LTM9001 16bit Receiver Subsystem, DC-300MHz LPF
• Tool / Board Applications: Wireless Connectivity-ZigBee, RF, Infrared, USB
• Mcu Supported Families: LTM9001
• Development Tool Type: Hardware - Eval/Demo Board
• For Use With/related Products: LTM9001
• Lead Free Status / RoHS Status: Not applicable / Not applicable

OPERATION
DYNAMIC PERFORMANCE DEFINITIONS
Signal-to-Noise Plus Distortion Ratio
The signal-to-noise plus distortion ratio [S/(N+D)] is the
ratio between the RMS amplitude of the fundamental input
frequency and the RMS amplitude of all other frequency
components at the ADC output.
Signal-to-Noise Ratio
The signal-to-noise (SNR) is the ratio between the RMS
amplitude of the fundamental input frequency and the RMS
amplitude of all other frequency components, except the
fi rst fi ve harmonics.
Total Harmonic Distortion
Total harmonic distortion is the ratio of the RMS sum
of all harmonics of the input signal to the fundamental
itself. The out-of-band harmonics alias into the frequency
band between DC and half the sampling frequency. THD
is expressed as:
where V1 is the RMS amplitude of the fundamental
frequency and V2 through Vn are the amplitudes of the
second through nth harmonics.
Intermodulation Distortion
If the input signal consists of more than one spectral
component, the transfer function nonlinearity can produce
intermodulation distortion (IMD) in addition to THD. IMD is
the change in one sinusoidal input caused by the presence
of another sinusoidal input at a different frequency.
If two pure sine waves of frequencies fa and fb are applied
to the input, nonlinearities in the transfer function can create
THD = –20Log
⎛
⎝
(V2
2
+ V3
2
+ V4
2
+ ...Vn
2
)/V1
⎞
⎠
distortion products at the sum and difference frequencies
of mfa ± nfb, where m and n = 0, 1, 2, 3, etc.
For example, the 3rd order IMD terms include (2fa + fb),
(fa + 2fb), (2fa – fb) and (fa – 2fb). The 3rd order IMD is
defi ned as the ration of the RMS value of either input tone
to the RMS value of the largest 3rd order IMD product.
Spurious Free Dynamic Range (SFDR)
The ratio of the RMS input signal amplitude to the RMS
value of the peak spurious spectral component expressed
in dBc. SFDR may also be calculated relative to full-scale
and expressed in dBFS.
Aperture Delay Time
Aperture delay is the time from when a rising ENC
the ENC
by the sample and-hold circuit.
Aperture Delay Jitter
The variation in the aperture delay time from conversion
to conversion. This random variation will result in noise
when sampling an AC input. The signal to noise ratio due
to the jitter alone will be:
DESCRIPTION
The LTM9001 is an integrated system in a package (SiP)
μModule
16-bit A/D converter, matching network, anti-aliasing fi lter
and a low noise, differential amplifi er with fi xed gain. It
is designed for digitizing high frequency, wide dynamic
range signals with an intermediate frequency (IF) range
up to 300MHz.
SNR
LTM9001-Ax/LTM9001-Bx
JITTER
–
®
voltage to the instant that the input signal is held
receiver that includes a high-speed, sampling
= –20log (2π • f
IN
• t
JITTER
)
+
17
equals
9001fc