MAX1282BEUE-T Maxim Integrated, MAX1282BEUE-T Datasheet - Page 19

• Manufacturer Part Number: MAX1282BEUE-T
• Description: Analog to Digital Converters - ADC
• Manufacturer: Maxim Integrated

Specifications of MAX1282BEUE-T

• Number Of Channels: 4/2
• Architecture: SAR
• Conversion Rate: 400 KSPs
• Resolution: 12 bit
• Input Type: Single-Ended/Pseudo-Differential
• Snr: Yes
• Interface Type: 4-Wire (SPI, Microwire, QSPI, TMS320)
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-16
• Maximum Power Dissipation: 535 mW
• Minimum Operating Temperature: - 40 C
• Number Of Converters: 1
• Voltage Reference: 2.5 V

Figure 17 shows an application circuit to interface the
MAX1282/MAX1283 to the TMS320 in external clock
mode. The timing diagram for this interface circuit is
shown in Figure 18.
Use the following steps to initiate a conversion in the
MAX1282/MAX1283 and to read the results:
1) The TMS320 should be configured with CLKX (trans-
Figure 12. MAX1282/MAX1283 Reference-Adjust Circuit
Figure 13. Unipolar Transfer Function, Full Scale (FS) =
V
REF
11 . . . 111
11 . . . 110
11 . . . 101
00 . . . 011
00 . . . 010
00 . . . 001
00 . . . 000
mit clock) as an active-high output clock and CLKR
(TMS320 receive clock) as an active-high input clock.
CLKX and CLKR on the TMS320 are connected to
the MAX1282/MAX1283’s SCLK input.
+ V
OUTPUT CODE
100k
24k
COM
(COM)
+3.3V
0
, Zero Scale (ZS) = V
1
300ksps/400ksps, Single-Supply, 4-Channel,
Serial 12-Bit ADCs with Internal Reference
2
INPUT VOLTAGE (LSB)
______________________________________________________________________________________
3
510k
0.047µF
TMS320LC3x Interface
FULL-SCALE
TRANSITION
COM
12
FS - 3/2LSB
REFADJ
MAX1282
MAX1283
1LSB =
FS = V
ZS = V
FS
REF
COM
4096
V
REF
+ V
COM
2) The MAX1282/MAX1283’s CS pin is driven low by the
3) An 8-bit word (1XXXXX11) should be written to the
4) The MAX1282/MAX1283’s SSTRB output is moni-
5) The TMS320 reads in 1 data bit on each of the next
6) Pull CS high to disable the MAX1282/MAX1283 until
Figure 14. Bipolar Transfer Function, Full Scale (FS) =
V
REF
*V
TMS320’s XF_ I/O port to enable data to be clocked
into the MAX1282/MAX1283’s DIN pin.
MAX1282/MAX1283 to initiate a conversion and
place the device into normal operating mode. See
Table 3 to select the proper XXXXX bit values for your
specific application.
tored through the TMS320’s FSR input. A falling
edge on the SSTRB output indicates that the conver-
sion is in progress and data is ready to be received
from the device.
16 rising edges of SCLK. These data bits represent
the 12-bit conversion result followed by 4 trailing bits,
which should be ignored.
the next conversion is initiated.
011 . . . 111
011 . . . 110
000 . . . 010
000 . . . 001
000 . . . 000
111 . . . 111
111 . . . 110
100 . . . 000
111 . . . 101
100 . . . 001
COM
/ 2 + V
≤
OUTPUT CODE
V
REF
COM
/ 2
-FS =
1LSB =
- FS
ZS = V
FS = V
, Zero Scale (ZS) = V
-V
COM
REF
2
REF
2
4096
V
REF
+ V
+ V
COM
COM
INPUT VOLTAGE (LSB)
COM*
COM
+FS - 1LSB
19