AD9020
PIN CONFIGURATION
61
60
9
NC
NC
SENSE
10
+V
+V
LSBs INVERT
NC
REF
–V
GND
SENSE
–V
+V
ENCODE
REF
+V
S
S
S
–V
–V
GND
S
AD9020
GND
+V
(LSB) D
0
+V
S
S
TOP VIEW
(NOT TO SCALE)
OVERFLOW
D
D
D
(MSB)
D
D
2
D
D
4
9
8
7
1
3
D
D
6
5
NC
+V
S
+V
S
26
27
NC
NC
44
43
NC = NO CONNECT
PIN FUNCTION DESCRIPTIONS
Function
Pin No.
Name
1
1/2REF
–VS
Midpoint of internal reference ladder.
2, 16, 28, 29, 35, 41, 42,
54, 64
Negative supply voltage; nominally –5.0 V 5%.
3, 6, 15, 18, 25, 30, 33, 34,
37, 40, 45, 52, 55, 65, 68
+VS
Positive supply voltage; nominally 5 V 5%.
4, 5, 13, 17, 27, 31, 32,
36, 38, 39, 43, 53, 66, 67
GROUND
All ground pins should be connected together and to low impedance ground
plane.
7
3/4REF
Three-quarter point of internal reference ladder.
Analog input; nominally between 1.75 V.
8, 9
11
ANALOG IN
+VSENSE
Voltage sense line to most positive point on internal resistor ladder.
Normally 1.75 V.
12
+VREF
Voltage force connection for top of internal reference ladder. Normally driven
to provide 1.75 V at +VSENSE
.
14
ENCODE
D0–D4, D5–D9
OVERFLOW
–VREF
TTL-compatible convert command used to begin digitizing process.
TTL-compatible digital output data.
19–23, 46–50
51
56
TTL-compatible output indicating ANALOG IN > +VSENSE
Voltage force connection for bottom of internal reference ladder. Normally
driven to provide –1.75 V at –VSENSE
.
.
57
59
61
63
–VSENSE
Voltage sense line to most negative point on internal resistor ladder.
Normally –1.75 V.
LSBs INVERT
MSB INVERT
1/4REF
Normally grounded. When connected to +VS, lower order bits (D0–D8) are
inverted.
Normally grounded. When connected to +VS, most significant bit (MSB; D9)
is inverted.
One-quarter point of internal reference ladder.
REV. C
–5–
ADI [ ADI ]
