2x4-Channel, Simultaneous-Sampling
12-Bit ADCs
______________________________________________________________Pin Description
PIN
1, 2
3, 4
5
NAME
FUNCTION
CH2B, CH2A
CH1B, CH1A
Channel 2 Multiplexed Inputs (single-ended)
Channel 1 Multiplexed Inputs (single-ended)
AV
Analog Supply Voltage
DD
6
REFIN
REFOUT
AGND
External reference input/internal reference output. Bypass with a 0.1µF capacitor to AGND.
ꢀ
Reference-Buffer output. Bypass with a 4.ꢀµF capacitor to AGND.
8, 36
9–16
1ꢀ
Analog ground. Both pins must be connected to ground.
Data Bits. D11 = MSB.
D11–D4
DV
Digital Supply Voltage
DD
18
DGND
D3, D2
D1/A3, D0/A2
A1, A0
CLK
Digital Ground
19, 20
21, 22
23, 24
25
Data Bits
Bidirectional Data Bits/Address Bits
Address Bits
Clock Input (duty cycle must be 30ꢁ to ꢀ0ꢁ). Connect CLK to DV to activate internal clock.
DD
26
Chip-Select Input (active-low)
CS
2ꢀ
Write Input (active-low)
WR
28
Read Input (active-low)
RD
29
Conversion-Start input. Rising edge initiates sampling and conversion sequence.
Interrupt output. Falling edge indicates the end of a conversion sequence.
Analog Supply Voltage
CONVST
INT
30
31
AV
SS
32, 33
34, 35
CH4A, CH4B
CH3A, CH3B
Channel 4 Multiplexed Inputs (single-ended)
Channel 3 Multiplexed Inputs (single-ended)
_______________Detailed Description
The MAX115/MAX116 use a successive-approximation
conversion technique and four simultaneous-sampling
1.6mA
track/hold (T/H) amplifiers to convert analog signals into
12-bit digital outputs. Each T/H has two multiplexed
inputs, allowing a total of eight inputs. Each T/H output
is converted and stored in memory to be accessed
sequentially by the parallel interface with successive
read cycles. The MAX115/MAX116 internal micro-
sequencer can be programmed to digitize one, two,
three, or four inputs sampled simultaneously from either
of the two banks of four inputs (Figure 2). The
MAX115/MAX116 can operate with either an external or
internal clock. For internal operation, connect CLK to
TO OUTPUT
1.6V
PIN
120pF
1.0mA
Figure 1. Load Circuit for Access Time and Bus Relinquish Time
DV
.
DD
6
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
