MX7828KP Maxim Integrated Products, MX7828KP Datasheet - Page 10

• Manufacturer Part Number: MX7828KP
• Description: ADC (A/D Converters) 8-Bit 8Ch Precision ADC
• Manufacturer: Maxim Integrated Products

Specifications of MX7828KP

• Architecture: Semiflash
• Conversion Rate: 400 KSPs
• Input Type: Voltage
• Maximum Power Dissipation: 75 mW
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Lead Free Status / Rohs Status: No

f
channel when using the MAX158/MX7828 and 100kHz
per channel when using the MAX154/MX7824. These
rates are well above the Nyquist requirement of 20kHz
sampling rate for a 10kHz input bandwidth.
The circuit in Figure 10a can be used for bipolar input
operation. The input voltage is scaled by an amplifier so
that only positive voltages appear at the ADC’s inputs.
An external reference should be used for the MX7824/
MX7828, but is not needed with the MAX154/MAX158.
The analog input range is ±4V and the output code is
complementary offset binary. The ideal input/output
characteristic is shown in Figure 10b.
CMOS, High-Speed, 8-Bit ADCs
with Multiplexer
Figure 9a. Equivalent Input Circuit
Figure 9b. RC Network Model
10
MAX
______________________________________________________________________________________
permits a maximum sampling rate of 50kHz per
V
R
V
S
IN
IN
R
S
AIN1
AIN1
C
2pF
S1
B MUX
R
C
12pF
600
MUX
S
Bipolar Input Operation
TO MS
LADDER
C
2pF
TO LS
LADDER
R
R
S
ON
ON
C
2pF
S2
350
R
16 MSB COMPARATORS
15 LSB COMPARATORS
ON
1pF
1pF
•
•
•
•
•
•
32pF
1pF
1pF
Figure 10a. Bipolar ±4V Input Operation
Figure 10b. Transfer Function for ±4V Input Operation
V
11111111
11111110
11111101
10000010
10000001
10000000
01111111
01111110
00000010
00000001
00000000
IN
ONLY CHANNEL 1 SHOWN
11.5
0.01 F
10.0k
0.1 F
+5V
-FS + 1LSB
2
16.2k
47 F
3.57k
0.01 F
AIN INPUT VOLTAGE (LSBs)
0V
AIN1
V
REF OUT
V
V
GND
REF
DD
REF
+
-
MAX154
MAX158
FS = 8V
1LSB = FS / 256
DB0–DB7
RDY
INT
CS
RD
+FS
2