MAX158AEWI+T Maxim Integrated, MAX158AEWI+T Datasheet - Page 8

• Manufacturer Part Number: MAX158AEWI+T
• Description: Analog to Digital Converters - ADC
• Manufacturer: Maxim Integrated

Specifications of MAX158AEWI+T

• Number Of Channels: 8
• Architecture: Half-Flash
• Conversion Rate: 400 KSPs
• Resolution: 8 bit
• Input Type: Single-Ended
• Snr: Yes
• Interface Type: Parallel
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Package / Case: SOIC-28 Wide
• Maximum Power Dissipation: 450 mW
• Minimum Operating Temperature: - 40 C
• Number Of Converters: 2
• Voltage Reference: 2.5 V

The V
zero and the full-scale of the ADC. In other words, the
voltage at V
duces an output code of all zeros, and the voltage at
V
code of all ones (Figure 7).
Figure 8 shows some possible reference configura-
tions. A 0.01µF bypass capacitor to GND should be
used to reduce the high-frequency output impedance
of the internal reference. Larger capacitors should not
be used, as this degrades the stability of the reference
buffer. The 2.5V reference output is with respect to the
GND pin.
A 47µF electrolytic and 0.1µF ceramic capacitor should
be used to bypass the V
tors must have minimum lead length, since excess lead
length may contribute to conversion errors and insta-
bility. If the reference inputs are driven by long lines,
they should be bypassed to GND with 0.1µF capac-
itors at the reference input pins.
CMOS High-Speed 8-Bit ADCs with
Multiplexer and Reference
_____________Analog Considerations
Figure 6. Mode 1 Timing Diagram
8
REF
CHANNEL
ADDRESS
ANALOG
_______________________________________________________________________________________
+ is equal to input voltage that produces an output
DATA
RDY
REF
INT
CS
RD
+ and V
REF
t
CSS
- is equal to the input voltage that pro-
REF
t
- inputs of the converter define the
AS
VALID
ADDR
t
RDY
DD
t
ACCI
t
AH
pin to GND. These capaci-
Reference and Input
t
RD
DATA
OLD
t
INTH
Bypassing
t
CRD
t
DH
t
CSH
Figure 7. Transfer Function
V
11111111
11111110
11111101
00000011
00000010
00000001
00000000
REF
-
t
CSS
OUTPUT
CODE
t
P
t
AS
1
2
ADDR
VALID
t
t
RDY
ACCI
t
AH
3
AIN INPUT VOLTAGE
(IN TERMS OF LSBs)
t
RD
1LSB = F8 = V
DATA
NEW
FULL-SCALE
TRANSITION
256
t
t
INTH
DH
t
REF
CSH
+ - V
256
FS–1LSB
REF
-
FS
V
REF
+