Linduino  1.3.0
Linear Technology Arduino-Compatible Demonstration Board

LTC1859: 16-bit 8-channel 100ksps ADC. More...

Detailed Description

LTC1859: 16-bit 8-channel 100ksps ADC.

The LTC1857/1858/LTC1859 are pin-compatible, 8-channel 12-/14-/16-bit A/D converters
with serial I/O, and an internal reference. The ADCs typically draw only 1.3mA
from a single 5V supply. The 8-channel input multiplexer can be configured for
either single-ended or differential inputs and unipolar or bipolar conversions
(or combinations thereof). The automatic nap and sleep modes benefit power
sensitive applications.

The LTC1859's DC performance is outstanding with a +/-2LSB INL specification and
no missing codes over temperature. The signal-to-noise ratio (SNR) for the
LTC1859 is typically 89dB, with the internal reference.

SPI DATA FORMAT (MSB First):

            Byte #1                           Byte #2
Data Out :  D15 D14 D13 D12 D11 D10  D9  D8    D7  D6  D5  D4  D3  D2  D1  D0
Data In  :  SD  OS  S1  S0  UNI GAIN NAP SLP   X   X   X   X   X   X   X   X

SD   : Single/Differential Bit
OS   : ODD/Sign Bit
Sx   : Address Select Bit
UNI  : Unipolar/Bipolar Bit
GAIN : Input Span Bit
NAP  : Nap Mode Bit
SLP  : Sleep Mode Bit
Dx   : Data Bits
X    : Don't care


Example Code:

Read Channel 0 in Single-Ended Unipolar mode when input is with respect to GND

    adc_command = LTC1859_CH0 | LTC1859_UNIPOLAR_MODE | LTC1859_LOW_GAIN_MODE | LTC1859_NORMAL_MODE;     // Single-ended, CH0, unipolar, low gain, normal mode.
    LTC1859_read(LTC1859_CS, adc_command, &adc_code);   // Throws out last reading
    LTC1859_read(LTC1859_CS, adc_command, &adc_code);   // Obtains the current reading and stores to adc_code variable

    // Convert adc_code to voltage
    adc_voltage = LTC1859_unipolar_code_to_voltage(adc_code, LTC1859_lsb, LTC1859_offset_unipolar_code);

http://www.linear.com/product/LTC1859

http://www.linear.com/product/LTC1859#demoboards

Copyright 2018(c) Analog Devices, Inc.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

  • Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
  • Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
  • Neither the name of Analog Devices, Inc. nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
  • The use of this software may or may not infringe the patent rights of one or more patent holders. This license does not release you from the requirement that you obtain separate licenses from these patent holders to use this software.
  • Use of the software either in source or binary form, must be run on or directly connected to an Analog Devices Inc. component.

THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Header for LTC1859: 16-bit 8-channel 100ksps ADC

Definition in file LTC1859.h.

Go to the source code of this file.

Functions

uint8_t LTC1859_build_command (uint8_t ch_designate, uint8_t uni_bipolar, uint8_t range_low_high)
 Builds the ADC command and returns an 8 bit command. More...
 
void LTC1859_read (uint8_t cs, uint8_t adc_command, uint16_t *adc_code)
 Reads the ADC and returns 16-bit data. More...
 
float LTC1859_code_to_voltage (uint16_t adc_code, float vref, uint8_t range_low_high, uint8_t uni_bipolar)
 Calculates the LTC1859 input's unipolar voltage given the binary data and lsb weight. More...
 

Macros

#define LTC1859_CS   QUIKEVAL_CS
 Define the SPI CS pin. More...
 
LTC1859 Single-Ended Channel Addresses
#define LTC1859_CH0   0x80
 
#define LTC1859_CH1   0xC0
 
#define LTC1859_CH2   0x90
 
#define LTC1859_CH3   0xD0
 
#define LTC1859_CH4   0xA0
 
#define LTC1859_CH5   0xE0
 
#define LTC1859_CH6   0xB0
 
#define LTC1859_CH7   0xF0
 
LTC1859 Differential Channel Addresses
#define LTC1859_P0_N1   0x00
 
#define LTC1859_P1_N0   0x40
 
#define LTC1859_P2_N3   0x10
 
#define LTC1859_P3_N2   0x50
 
#define LTC1859_P4_N5   0x20
 
#define LTC1859_P5_N4   0x60
 
#define LTC1859_P6_N7   0x30
 
#define LTC1859_P7_N6   0x70
 
LTC1859 Uni/GAIN config bits
#define LTC1859_UNIPOLAR_MODE   0x08
 
#define LTC1859_BIPOLAR_MODE   0x00
 
#define LTC1859_SINGLE_ENDED_MODE   0x80
 
#define LTC1859_DIFFERENTIAL_MODE   0x00
 
#define LTC1859_LOW_RANGE_MODE   0x00
 
#define LTC1859_HIGH_RANGE_MODE   0x04
 
LTC1859 Sleep/Nap config bits
#define LTC1859_SLEEP_MODE   0x01
 
#define LTC1859_NORMAL_MODE   0x00
 
#define LTC1859_NAP_MODE   0x02
 

Function Documentation

◆ LTC1859_build_command()

uint8_t LTC1859_build_command ( uint8_t  ch_designate,
uint8_t  uni_bipolar,
uint8_t  range_low_high 
)

Builds the ADC command and returns an 8 bit command.

Returns
8 bit command

Definition at line 77 of file LTC1859.cpp.

◆ LTC1859_code_to_voltage()

float LTC1859_code_to_voltage ( uint16_t  adc_code,
float  vref,
uint8_t  range_low_high,
uint8_t  uni_bipolar 
)

Calculates the LTC1859 input's unipolar voltage given the binary data and lsb weight.

Returns
Floating point voltage
Parameters
adc_codeRaw ADC code
range_low_high)

Definition at line 93 of file LTC1859.cpp.

◆ LTC1859_read()

void LTC1859_read ( uint8_t  cs,
uint8_t  adc_command,
uint16_t *  adc_code 
)

Reads the ADC and returns 16-bit data.

Returns
void
Parameters
csChip Select Pin
adc_commandChannel address, config bits ORed together
adc_codeReturns code read from ADC (from previous conversion)

Definition at line 86 of file LTC1859.cpp.

Macro Definition Documentation

◆ LTC1859_BIPOLAR_MODE

#define LTC1859_BIPOLAR_MODE   0x00

Definition at line 134 of file LTC1859.h.

◆ LTC1859_CH0

#define LTC1859_CH0   0x80

Definition at line 104 of file LTC1859.h.

◆ LTC1859_CH1

#define LTC1859_CH1   0xC0

Definition at line 105 of file LTC1859.h.

◆ LTC1859_CH2

#define LTC1859_CH2   0x90

Definition at line 106 of file LTC1859.h.

◆ LTC1859_CH3

#define LTC1859_CH3   0xD0

Definition at line 107 of file LTC1859.h.

◆ LTC1859_CH4

#define LTC1859_CH4   0xA0

Definition at line 108 of file LTC1859.h.

◆ LTC1859_CH5

#define LTC1859_CH5   0xE0

Definition at line 109 of file LTC1859.h.

◆ LTC1859_CH6

#define LTC1859_CH6   0xB0

Definition at line 110 of file LTC1859.h.

◆ LTC1859_CH7

#define LTC1859_CH7   0xF0

Definition at line 111 of file LTC1859.h.

◆ LTC1859_CS

#define LTC1859_CS   QUIKEVAL_CS

Define the SPI CS pin.

Definition at line 98 of file LTC1859.h.

◆ LTC1859_DIFFERENTIAL_MODE

#define LTC1859_DIFFERENTIAL_MODE   0x00

Definition at line 137 of file LTC1859.h.

◆ LTC1859_HIGH_RANGE_MODE

#define LTC1859_HIGH_RANGE_MODE   0x04

Definition at line 140 of file LTC1859.h.

◆ LTC1859_LOW_RANGE_MODE

#define LTC1859_LOW_RANGE_MODE   0x00

Definition at line 139 of file LTC1859.h.

◆ LTC1859_NAP_MODE

#define LTC1859_NAP_MODE   0x02

Definition at line 149 of file LTC1859.h.

◆ LTC1859_NORMAL_MODE

#define LTC1859_NORMAL_MODE   0x00

Definition at line 147 of file LTC1859.h.

◆ LTC1859_P0_N1

#define LTC1859_P0_N1   0x00

Definition at line 117 of file LTC1859.h.

◆ LTC1859_P1_N0

#define LTC1859_P1_N0   0x40

Definition at line 118 of file LTC1859.h.

◆ LTC1859_P2_N3

#define LTC1859_P2_N3   0x10

Definition at line 120 of file LTC1859.h.

◆ LTC1859_P3_N2

#define LTC1859_P3_N2   0x50

Definition at line 121 of file LTC1859.h.

◆ LTC1859_P4_N5

#define LTC1859_P4_N5   0x20

Definition at line 123 of file LTC1859.h.

◆ LTC1859_P5_N4

#define LTC1859_P5_N4   0x60

Definition at line 124 of file LTC1859.h.

◆ LTC1859_P6_N7

#define LTC1859_P6_N7   0x30

Definition at line 126 of file LTC1859.h.

◆ LTC1859_P7_N6

#define LTC1859_P7_N6   0x70

Definition at line 127 of file LTC1859.h.

◆ LTC1859_SINGLE_ENDED_MODE

#define LTC1859_SINGLE_ENDED_MODE   0x80

Definition at line 136 of file LTC1859.h.

◆ LTC1859_SLEEP_MODE

#define LTC1859_SLEEP_MODE   0x01

Definition at line 146 of file LTC1859.h.

◆ LTC1859_UNIPOLAR_MODE

#define LTC1859_UNIPOLAR_MODE   0x08

Definition at line 133 of file LTC1859.h.