MAX1027BCEE+ Maxim Integrated Products, MAX1027BCEE+ Datasheet - Page 12

• Manufacturer Part Number: MAX1027BCEE+
• Description: IC ADC 10-BIT 300KSPS 16-QSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1027BCEE+

• Number Of Bits: 10
• Sampling Rate (per Second): 300k
• Data Interface: MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 667mW
• Voltage Supply Source: Single Supply
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP (0.150", 3.90mm Width)
• Number Of Adc Inputs: 8
• Architecture: Dual-Slope
• Conversion Rate: 300 KSPs
• Resolution: 10 bit
• Input Type: Differential
• Interface Type: 3-Wire (SPI, QSPI, MICROWIRE)
• Voltage Reference: Internal 2.5 V or External
• Supply Voltage (max): 3 V
• Maximum Power Dissipation: 667 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference
temperature measurement is performed before the first
temperature result is read out, the old measurement is
overwritten by the new result. Temperature results are
in degrees Celsius (two’s complement) at a resolution
of 1/8 of a degree. See the Temperature Measurements
section for details on converting the digital code to a
temperature.
The MAX1027/MAX1029/MAX1031 operate from an inter-
nal oscillator, which is accurate within 10% of the 4.4MHz
nominal clock rate. The internal oscillator is active in
clock modes 00, 01, and 10. Read out the data at clock
speeds up to 10MHz. See Figures 4–7 for details on tim-
ing specifications and starting a conversion.
The MAX1027/MAX1029/MAX1031 communicate
between the internal registers and the external circuitry
through the SPI/QSPI-compatible serial interface. Table
1 details the registers and the bit names. Tables 2–7
show the various functions within the conversion regis-
ter, setup register, averaging register, reset register,
unipolar register, and bipolar register.
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 conver-
sion time for an internally timed conversion in clock
modes 00 and 10 (see the Electrical Characteristics
section as applicable):
12
Table 1. Input Data Byte (MSB First)
* Unipolar/bipolar channels 8–15 are only valid on the MAX1029 and MAX1031.
** Unipolar/bipolar channels 12–15 are only valid on the MAX1031.
X = Don’t care.
Conversion
Setup
Averaging
Reset
Unipolar Mode (Setup)
Bipolar Mode (Setup)
REGISTER NAME
______________________________________________________________________________________
Applications Information
Conversion Time Calculations
UCH0/1
BCH0/1
BIT 7
Register Descriptions
1
0
0
0
CHSEL3
UCH2/3
BCH1/2
Internal Clock
BIT 6
1
0
0
CHSEL2
CKSEL1
UCH4/5
BCH4/5
BIT 5
1
0
CHSEL1
CKSEL0
AVGON
UCH6/7
BCH6/7
where:
t
n
n
by number of channels being scanned or by NSCAN1,
NSCAN0
t
to zero if temp measurement is not requested
t
nal reference is already powered up or if the external
reference is being used
In clock mode 01, the total conversion time depends on
how long CNVST is held low or high, including any time
required to turn on the internal reference. 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.
Select active analog input channels, scan modes, and
a single temperature measurement per scan by writing
to the conversion register. Table 2 details channel
selection, the four scan modes, and how to request a
temperature measurement. Request a scan by writing
to the conversion register when in clock mode 10 or 11,
or by applying a low pulse to the CNVST pin when in
clock mode 00 or 01.
A conversion is not performed if it is requested on a
channel that has been configured as CNVST or REF-.
Do not request conversions on channels 8–15 on the
MAX1027 and channels 12–15 on the MAX1029. Set
CHSEL3:CHSEL0 to the lower channel’s binary value. If
the last two channels are configured as a differential
cnv
TS
RP
BIT 4
total conversion time = t
avg
result
1
= internal reference wake-up; set to zero if the inter-
= time required for temperature measurement; set
= t
= samples per result (amount of averaging)
= number of FIFO results requested; determined
acq
(max) + t
REFSEL1
UCH8/9*
BCH8/9*
CHSEL0
NAVG1
RESET
BIT 3
conv
UCH10/11* UCH12/13** UCH14/15**
BCH10/11* BCH12/13** BCH14/15**
REFSEL0
NAVG0
SCAN1
(max)
BIT 2
cnv
X
x n
avg
Conversion Register
DIFFSEL1
NSCAN1
SCAN0
x n
BIT 1
X
result
+ t
DIFFSEL0
NSCAN0
TS
TEMP
BIT 0
X
+ t
RP