5

LTC1409

Note 11: The falling CONVST edge starts a conversion. If CONVST returns

high at a critical point during the conversion it can create small errors. For

best results ensure that CONVST returns high either within 650ns after

conversion start or after BUSY rises.

TI I G CHARACTERISTICS

Note 12: Signal-to-noise ratio (SNR) is measured at 100kHz and distortion

is measured at 400kHz. These results are used to calculate signal-to-noise

plus distortion (SINAD).

S/(N + D) vs Input Frequency

and Amplitude

INPUT FREQUENCY (Hz)

1k

80

70

60

50

40

30

20

10

0

10k

100k

LTC1409 • TPC01

1M

10M

INPUT FREQUENCY (Hz)

1k

80

70

60

50

40

30

20

10

0

10k

100k

LTC1409 • TPC02

1M

10M

Signal-to-Noise Ratio vs

Input Frequency

Spurious-Free Dynamic Range vs

Input Frequency

INPUT FREQUENCY (Hz)

10k

0

–10

–20

–30

–40

–50

–60

–70

–80

–90

–100

100k

1M

10M

LTC1409 • TPC04

Distortion vs Input Frequency

INPUT FREQUENCY (Hz)

0

–10

–20

–30

–40

–50

–60

–70

–80

–90

–100

1k

100k

1M

10M

LTC1409 • TPC03

10k

THD

3RD

2ND

Intermodulation Distortion Plot

FREQUENCY (Hz)

0

0

–20

–40

–60

–80

–100

–120

100k

200k

300k

400k

LTC1409 • TPC05

50k

150k

250k

350k

fb – fa

2fb – fa

2fa – fb

2fa

2fb

3fb

fa + 2fb

3fa

2fa + fb

fa + fb