AD7892AN-1 Analog Devices Inc, AD7892AN-1 Datasheet - Page 11

• Manufacturer Part Number: AD7892AN-1
• Description: IC ADC 12BIT LP 500KSPS 24-DIP
• Manufacturer: Analog Devices Inc

Specifications of AD7892AN-1

• Mounting Type: Through Hole
• Package / Case: 24-DIP (0.300", 7.62mm)
• Rohs Status: RoHS non-compliant
• Number Of Bits: 12
• Sampling Rate (per Second): 500k
• Data Interface: Serial, Parallel
• Number Of Converters: 1
• Power Dissipation (max): 90mW
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• No. Of Bits: 12 Bit
• Features: Single Supply, 12?Bit, 500kSPS ADC
• No. Of Channels: 1
• Interface Type: Parallel
• Number Of Elements: 1
• Resolution: 12Bit
• Architecture: SAR
• Sample Rate: 500KSPS
• Input Polarity: Bipolar
• Input Type: Voltage
• Rated Input Volt: ±5/±10V
• Differential Input: No
• Power Supply Requirement: Single
• Single Supply Voltage (typ): 5V
• Single Supply Voltage (min): 4.75V
• Single Supply Voltage (max): 5.25V
• Dual Supply Voltage (typ): Not RequiredV
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Power Dissipation: 90mW
• Differential Linearity Error: ±1LSB
• Integral Nonlinearity Error: ±1.5LSB
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Through Hole
• Pin Count: 24
• Package Type: PDIP
• Input Signal Type: Single-Ended
• Lead Free Status / Rohs Status: Not Compliant

The designed code transitions occur midway between successive
integer LSB values (i.e., 1/2 LSB, 3/2 LSBs, 5/2 LSBs). Output
coding is two’s complement binary with 1 LSB = FSR/4096 =
20 V/4096 = 4.88 mV for the ± 10 V range and 1 LSB = FSR/
4096 = 10 V/4096 = 2.44 mV for the ± 5 V range. The ideal
input/output transfer function for the AD7892-1 is shown in
Table I.
AD7892-2
The analog input section for the AD7892-2 contains no biasing
resistors. The analog input looks directly into the track/hold
input stage. The analog input range on the V
+2.5 V. The V
connected to a potential then that potential must be AGND.
The V
of the AD7892-2’s track/hold. The value of this input sampling
capacitor is nominally 10 pF.
Once again, the designed code transitions occur midway be-
tween successive integer LSB values (i.e., 1/2 LSB, 3/2 LSBs,
5/2 LSBs). Output coding is straight (natural) binary with
1 LSB = FSR/4096 = 2.5 V/4096 = 0.61 mV. The ideal input/
output transfer function for the AD7892-2 is shown in Table II.
Analog Input
+FSR/2 – 3/2 LSB
+FSR/2 – 5/2 LSBs (9.98779 or 4.99390)
+FSR/2 – 7/2 LSBs (9.98291 or 4.99146)
AGND + 3/2 LSB (0.00732 or 0.00366)
AGND + 1/2 LSB (0.00244 or 0.00122)
AGND – 1/2 LSB (–0.00244 or –0.00122)
AGND – 3/2 LSB (–0.00732 or –0.00366)
–FSR/2 + 5/2 LSB (–9.98779 or –4.99390)
–FSR/2 + 3/2 LSB (–9.99268 or –4.99634)
–FSR/2 + 1/2 LSB (–9.99756 or –4.99878)
NOTES
1
2
3
Analog Input
+FSR – 3/2 LSB
+FSR – 5/2 LSBs (2.498474 V)
+FSR – 7/2 LSBs (2.497864 V)
AGND + 5/2 LSB (0.001526 V)
AGND + 3/2 LSB (0.00916 V)
AGND + 1/2 LSB (0.000305 V)
NOTES
1
2
FSR is full-scale range and REF IN = +2.5 V, is 20 V for the ± 10 V range and 10 V
1 LSB = FSR/4096 = 4.88 mV (± 10 V range) and 2.44 mV (± 5 V range) with REF
± 10 V range or ± 5 V range.
FSR is full-scale range and is 2.5 V with REF IN = +2.5 V.
1 LSB = FSR/4096 = 0.61 mV with REF IN = +2.5 V.
for the ± 5 V range.
IN = +2.5 V.
Table II. Ideal Input/Output Code Table for the AD7892-2
Table I. Ideal Input/Output Code Table for the AD7892-1
IN1
input connects directly to the input sampling capacitor
1, 2
IN2
1, 2
(2.499084 V)
input can be left unconnected but if it is
(9.99268 or 4.99634)
Digital Output
Code Transition
111 . . . 110 to 111 . . . 111
111 . . . 110 to 111 . . . 110
111 . . . 100 to 111 . . . 101
000 . . . 010 to 010 . . . 011
000 . . . 001 to 001 . . . 010
000 . . . 000 to 000 . . . 001
3
011 . . . 110 to 011 . . . 111
011 . . . 101 to 011 . . . 110
011 . . . 100 to 011 . . . 101
000 . . . 001 to 000 . . . 010
000 . . . 000 to 000 . . . 001
111 . . . 111 to 000 . . . 000
111 . . . 110 to 111 . . . 111
100 . . . 010 to 100 . . . 011
100 . . . 001 to 100 . . . 010
100 . . . 000 to 100 . . . 001
Digital Output
Code Transition
IN1
input is 0 V to
AD7892-3
Figure 5 shows the analog input section for the AD7892-3. The
analog input range is ± 2.5 V on the V
can be left unconnected but if it is connected to a potential then
that potential must be AGND. The input resistance on the V
is 1.8 kΩ nominal. As a result, the V
from a low impedance source. The resistor attenuator stage is
followed by the high input impedance stage of the track/hold
amplifier. This resistor attenuator stage allows the input voltage
to go to ± 7 V without damaging the AD7892-3.
The designed code transitions occur midway between succes-
sive integer LSB values (i.e., 1/2 LSB, 3/2 LSBs, 5/2 LSBs).
Output coding is two’s complement binary with 1 LSB = FSR/
4096 = 5 V/4096 = 1.22 mV with REF IN = +2.5 V. The ideal
input/output transfer function for the AD7892-3 is shown in
Table III.
Analog Input
+FSR/2 – 3/2 LSB
+FSR/2 – 5/2 LSBs (2.49695)
+FSR/2 – 7/2 LSBs (2.49573)
AGND + 3/2 LSB (0.00183)
AGND + 1/2 LSB (0.00061)
AGND – 1/2 LSB (–0.00061)
AGND – 3/2 LSB (–0.00183)
–FSR/2 + 5/2 LSB (–2.49695)
–FSR/2 + 3/2 LSB (–2.49817)
–FSR/2 + 1/2 LSB (–2.49939)
NOTES
1
2
FSR is full-scale range and is 5 V with REF IN = +2.5 V.
1 LSB = FSR/4096 = 1.22 mV with REF IN = +2.5 V.
Table III. Ideal Input/Output Code Table for the AD7892-3
REF OUT/
REF IN
AGND
V
V
IN2
IN1
*
1, 2
* UNCONNECTED INTERNALLY ON THE AD7892-3
(2.49817)
2k
3.25k
REFERENCE
3.25k
+2.5
IN1
IN1
Digital Output
Code Transition
011 . . . 110 to 011 . . . 111
011 . . . 110 to 011 . . . 110
011 . . . 110 to 011 . . . 101
000 . . . 001 to 000 . . . 010
000 . . . 000 to 000 . . . 001
111 . . . 111 to 000 . . . 000
111 . . . 110 to 111 . . . 111
100 . . . 010 to 100 . . . 011
100 . . . 001 to 100 . . . 010
100 . . . 000 to 100 . . . 001
input should be driven
input. The V
TO ADC
REFERENCE
CIRCUITRY
TO HIGH
IMPEDANCE
SHA INPUT
AD7892
IN2
input
IN1