hi5766 Intersil Corporation, hi5766 Datasheet - Page 14

• Manufacturer Part Number: hi5766
• Description: 10-bit, 60msps A/d Converter
• Manufacturer: Intersil Corporation

NOTES:
The output enable pin, OE, when pulled high will three-state
the digital outputs to a high impedance state. Set the OE
input to logic low for normal operation.
Supply and Ground Considerations
The HI5766 has separate analog and digital supply and
ground pins to keep digital noise out of the analog signal path.
The digital data outputs also have a separate supply pin,
DV
allows the outputs to interface with 3V logic if so desired.
The part should be mounted on a board that provides
separate low impedance connections for the analog and
digital supplies and grounds. For best performance, the
supplies to the HI5766 should be driven by clean, linear
regulated supplies. The board should also have good high
frequency decoupling capacitors mounted as close as
possible to the converter. If the part is powered off a single
supply then the analog supply should be isolated with a
ferrite bead from the digital supply.
Refer to the application note “Using Intersil High Speed A/D
Converters” (AN9214) for additional considerations when
using high speed converters.
Static Performance Definitions
Offset Error (V
The midscale code transition should occur at a level
above half-scale. Offset is defined as the deviation of the
actual code transition from this point.
+Full Scale (+FS) -
+FS
+
-
-FS + 1
-Full Scale (-FS) +
8. The voltages listed above represent the ideal center of each output code shown as a function of the reference differential voltage,
9. V
1
3
/
/
4
CC2
4
(V
LSB
-
LSB
REF
CODE CENTER
DESCRIPTION
REF
1
1
3
, which can be powered from a 3V or 5V supply. This
/
/
+ = 2.5V and V
4
4
+ - V
LSB
LSB
OE INPUT
REF
0
1
OS
1
3
-) = 0.5V.
/
/
4
4
LSB
LSB
)
REF
- = 2V.
DIFFERENTIAL
(V
-244.141µV
-0.498291V
-0.499268V
14
VOLTAGE
0.499756V
0.498779V
732.422µV
IN
INPUT
+ - V
DIGITAL DATA OUTPUTS
IN
High Impedance
-)
Active
D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
M
S
B
1
1
1
0
0
0
1
1
0
1
0
0
OFFSET BINARY OUTPUT CODE
TABLE 1. A/D CODE TABLE
1
1
1
0
1
0
0
/
4
LSB
1
1
0
1
0
0
(DFS LOW)
HI5766
1
1
0
1
0
0
1
1
0
1
0
0
Full-Scale Error (FSE)
The last code transition should occur for an analog input that
is
error removed. Full Scale error is defined as the deviation of
the actual code transition from this point.
Differential Linearity Error (DNL)
DNL is the worst case deviation of a code width from the
ideal value of 1 LSB.
Integral Linearity Error (INL)
INL is the worst case deviation of a code center from a best
fit straight line calculated from the measured data.
Power Supply Sensitivity
Each of the power supplies are moved plus and minus 5% and
the shift in the offset and full scale error (in LSBs) is noted.
Dynamic Performance Definitions
Fast Fourier Transform (FFT) techniques are used to evaluate
the dynamic performance of the HI5766. A low distortion sine
wave is applied to the input, it is coherently sampled, and the
output is stored in RAM. The data is then transformed into the
frequency domain with an FFT and analyzed to evaluate the
dynamic performance of the A/D. The sine wave input to the
part is -0.5dB down from Full scale for all these tests.
SNR and SINAD are quoted in dB. The distortion numbers are
quoted in dBc (decibels with respect to carrier) and DO NOT
include any correction factors for normalizing to full scale.
Effective Number Of Bits (ENOB)
The effective number of bits (ENOB) is calculated from the
SINAD data by:
ENOB = (SINAD - 1.76 + V
1
1
0
1
0
0
3
/
4
1
1
0
1
0
0
LSBs below positive Full Scale (+FS) with the offset
1
1
0
1
0
0
B
L
S
1
0
0
1
1
0
M
B
S
0
0
0
1
1
1
TWO’S COMPLEMENT OUTPUT CODE
1
1
0
1
0
0
CORR
1
1
0
1
0
0
1
1
0
1
0
0
) / 6.02
(DFS HIGH)
1
1
0
1
0
0
1
1
0
1
0
0
1
1
0
1
0
0
1
1
0
1
0
0
1
1
0
1
0
0
S
B
L
1
0
0
1
1
0