MAX1042BETX+T Maxim Integrated Products, MAX1042BETX+T Datasheet - Page 32

• Manufacturer Part Number: MAX1042BETX+T
• Description: IC ADC/DAC 10BIT W/FIFO 36TQFN
• Manufacturer: Maxim Integrated Products
• Type: ADC, DACr

Specifications of MAX1042BETX+T

• Resolution (bits): 10 b
• Sampling Rate (per Second): 225k
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Voltage Supply Source: Analog and Digital
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 36-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10-Bit, Multichannel ADCs/DACs with FIFO,
Temperature Sensing, and GPIO Ports
In clock mode 11, acquisitions and conversions are ini-
tiated by writing a command byte to the conversion
register and are performed one at a time using SCLK
as the conversion clock. Scanning, averaging and the
FIFO are disabled, and the conversion result is avail-
able at DOUT during the conversion. Output data is
updated on the rising edge of SCLK in clock mode 11.
See Figure 9 for clock mode 11 timing.
Initiate a conversion by writing a command byte to the
conversion register followed by 16 SCLK cycles. If CS
is pulsed high between the eighth and ninth cycles, the
pulse width must be less than 100µs. To continuously
convert at 16 cycles per conversion, alternate 1 byte of
zeros (NOP byte) between each conversion byte. If 2
NOP bytes follow a conversion byte, the analog cells
power down at the end of the second NOP. Set the
FBGON bit to one in the reset register to keep the inter-
nal bias block powered.
If reference mode 00 is requested, or if an external refer-
ence is selected but a temperature measurement is being
requested, wait 45µs with CS high after writing the con-
version byte to extend the acquisition and allow the inter-
nal reference to power up. To perform a temperature
measurement, write 24 bytes (192 cycles) of zeros after
the conversion byte. The temperature result appears on
DOUT during the last 2 bytes of the 192 cycles.
Temperature results are available in 12-bit format.
Figure 9. Clock Mode 11—Externally Timed Acquisition, Sampling, and Conversion without CNVST
32
DOUT
X = DON'T CARE.
SCLK
EOC
DIN
CS
______________________________________________________________________________________
Conversions Using the Serial Interface
Externally Clocked Acquisitions and
ADC Conversions in Clock Mode 11
(ACQUISITION1)
(CONVERSION BYTE)
MSB1
(CONVERSION1)
The conversion time for each scan is based on a num-
ber of different factors: conversion time per sample,
samples per result, results per scan, if a temperature
measurement is requested, and if the external refer-
ence is in use. Use the following formula to calculate
the total conversion time for an internally timed conver-
sion in clock mode 00 and 10 (see the Electrical
Characteristics , as applicable):
where:
t
and reference mode selected)
n
n
to one unless [SCAN1, SCAN0] = 10
t
(53.1µs); set to zero if temperature measurement is not
requested
t
conversion using the external reference is requested
In clock mode 01, the total conversion time depends on
how long CNVST is held low or high. Conversion time in
externally clocked mode (CKSEL1, CKSEL0 = 11)
depends on the SCLK period and how long CS is held
high between each set of eight SCLK cycles. In clock
mode 01, the total conversion time does not include the
time required to turn on the internal reference.
CNV
TS
INT-REF,SU
AVG
SCAN
= time required for temperature measurement
= t
= samples per result (amount of averaging)
= number of times each channel is scanned; set
t
CNV
DOV
= t
x n
(where t
WU
AVG
LSB1
Total conversion time =
(external-reference wake-up); if a
x n
DOV
(ACQUISITION2)
SCAN
Conversion-Time Calculations
is dependent on clock mode
+ t
TS
+ t
INT-REF,SU
MSB2