PIN ASSIGNMENTS
PIN CONFIGURATION
Top View
DIP/SOIC
PIN # NAME
DESCRIPTION
1
2
3
IN1
IN2
±10V Analog Input. Connected to GND for ±5V range.
±5V Analog Input. Connected to GND for ±10V range.
REF
+2V Reference Output. Bypass to GND with 22µF to
47µF Tantalum. Buffer for external loads.
IN1
IN2
1
2
3
4
5
6
7
8
9
24 VSA
23 VSD
22 –VS
21 BUSY
20 CS
19 R/C
18 HBE
17 D0
4
5
AGND
D11
D10
D9
Analog Ground. Connect to pin 13.
Data Bit 11. Most Significant Bit (MSB).
Data Bit 10.
REF
AGND
D11
D10
D9
6
7
Data Bit 9.
8
D8
Data Bit 8.
9
D7
Data Bit 7 if HBE is LOW; LOW if HBE is HIGH.
Data Bit 6 if HBE is LOW; LOW if HBE is HIGH.
Data Bit 5 if HBE is LOW; LOW if HBE is HIGH.
Data Bit 4 if HBE is LOW; LOW if HBE is HIGH.
Digital Ground. Connect to pin 4.
10
11
12
13
14
15
16
17
D6
D5
D4
D8
DGND
D3
Data Bit 3 if HBE is LOW; Data Bit 11 if HBE is HIGH.
Data Bit 2 if HBE is LOW; Data Bit 10 if HBE is HIGH.
Data Bit 1 if HBE is LOW; Data Bit 9 if HBE is HIGH.
D7
16 D1
D2
D6 10
D5 11
D4 12
15 D2
D1
14 D3
D0
Data Bit 0 if HBE is LOW. Least Significant Bit (LSB);
Data Bit 8 if HBE is HIGH.
13 DGND
18
HBE
High Byte Enable. When held LOW, data output as 12
bits in parallel. When held HIGH, four MSBs presented on
pins 14-17, pins 9-12 output LOWs. Must be LOW to
initiate conversion.
19
20
21
R/C
CS
Read/Convert. Falling edge initiates conversion when CS
is LOW, HBE is LOW, and BUSY is HIGH.
Chip Select. Outputs in Hi-Z state when HIGH. Must be
LOW to initiate conversion or read data.
BUSY
Busy. Output LOW during conversion. Data valid on rising
edge in Convert Mode.
22
23
–VS
VSD
Negative Power Supply. –12V or –15V. Bypass to GND.
Positive Digital Power Supply. +5V. Connect to pin 24,
and bypass to GND.
24
VSA
Positive Analog Power Supply. +5V. Connect to pin 23,
and bypass to GND.
ADS7800
4
SBAS001A
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