MAX1077ETC+ Maxim Integrated Products, MAX1077ETC+ Datasheet - Page 11

• Manufacturer Part Number: MAX1077ETC+
• Description: IC ADC 10BIT 1.5MSPS 12-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX1077ETC+

• Number Of Bits: 10
• Sampling Rate (per Second): 1.5M
• Data Interface: MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 22mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 12-WQFN Exposed Pad
• Number Of Adc Inputs: 1
• Architecture: SAR
• Conversion Rate: 1500 KSPs
• Resolution: 10 bit
• Input Type: Differential
• Interface Type: 3-Wire (SPI, QSPI, MICROWIRE)
• Voltage Reference: Internal 2.048 V or External
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.7 V
• Maximum Power Dissipation: 1349 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX1077/MAX1079 have an on-chip voltage refer-
ence trimmed to 2.048V. The internal reference output
is connected to REF and also drives the internal capac-
itive DAC. The output can be used as a reference volt-
age source for other components and can source up to
2mA. Bypass REF with a 0.01µF capacitor and a 4.7µF
capacitor to RGND.
The internal reference is continuously powered up dur-
ing both normal and partial power-down modes. In full
power-down mode, the internal reference is disabled.
Be sure to allow at least 2ms recovery time after hard-
ware power-up or exiting full power-down mode for the
reference to reach its intended value.
An analog-to-digital conversion is initiated by CNVST
and clocked by SCLK, and the resulting data is clocked
out on DOUT by SCLK. With SCLK idling high or low, a
falling edge on CNVST begins a conversion. This causes
the analog input stage to transition from track to hold
mode and DOUT to transition from high impedance to
being actively driven low. A total of 16 SCLK cycles are
required to complete a normal conversion. If CNVST is
low during the 16th falling SCLK edge, DOUT returns to
high impedance on the next rising edge of CNVST or
SCLK, enabling the serial interface to be shared by multi-
ple devices. If CNVST returns high after the 14th, but
before the 16th SCLK rising edge, DOUT remains active
so continuous conversions can be sustained. The high-
est throughput is achieved when performing continuous
conversions. Figure 10 illustrates a conversion using a
typical serial interface.
The MAX1077/MAX1079 serial interface is fully compati-
ble with SPI/QSPI and MICROWIRE (see Figure 11). If a
serial interface is available, set the CPU’s serial interface
in master mode so the CPU generates the serial clock.
Choose a clock frequency up to 24MHz.
When using SPI or MICROWIRE, the MAX1077/MAX1079
are compatible with all four modes programmed with the
CPHA and CPOL bits in the SPI or MICROWIRE control
register. Conversion begins with a CNVST falling edge.
DOUT goes low, indicating a conversion is in progress.
Two consecutive 1-byte reads are required to get the full
10 bits from the ADC. DOUT transitions on SCLK rising
edges. DOUT is guaranteed to be valid t
Differential, 10-Bit ADCs with Internal Reference
Applications Information
1.5Msps, Single-Supply, Low-Power, True-
______________________________________________________________________________________
How to Start a Conversion
Standard Interfaces
SPI and MICROWIRE
Internal Reference
Connection to
DOUT
later and
Figure 8. Unipolar Transfer Function (MAX1077 Only)
Figure 9. Bipolar Transfer Function (MAX1079 Only)
111...111
111...110
111...101
000...011
000...010
000...001
000...000
011...111
011...110
000...010
000...001
000...000
111...111
111...110
111...101
100...001
100...000
OUTPUT CODE
OUTPUT CODE
0
-FS
1
2
1 LSB =
- FS =
FS =
ZS = 0
3
V
1024
V
-V
REF
REF
2
2
REF
DIFFERENTIAL INPUT
DIFFERENTIAL INPUT
VOLTAGE (LSB)
VOLTAGE (LSB)
0
FULL-SCALE
TRANSITION
TRANSITION
FULL-SCALE
FS - 3/2 LSB
FS - 3/2 LSB
1 LSB =
FS = V
ZS = 0
FS
V
1024
FS
REF
REF
11