![]() |
Linduino
1.3.0
Linear Technology Arduino-Compatible Demonstration Board
|
LTC2636: Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference. More...
LTC2636: Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference.
LTC2634: Quad 12-/10-/8-Bit Rail-to-Rail DACs with 10ppm/°C Reference.
The LTC2636 is a family of quad 16-/12-bit rail-to-rail DACs with integrated 10ppm/C maximum reference. The DACs have built-in high performance, rail-to- rail, output buffers and are guaranteed monotonic. The LTC2636-L has a full- scale output of 2.5V with the integrated reference and operates from a single 2.7V to 5.5V supply. The LTC2636-H has a full-scale output of 4.096V with the integrated reference and operates from a 4.5V to 5.5V supply. Each DAC can also operate with an external reference, which sets the full-scale output to 2 times the external reference voltage. These DACs communicate via a SPI/MICROWIRE compatible 4-wire serial interface which operates at clock rates up to 50MHz. The LTC2636 incorporates a power-on reset circuit that is controlled by the PORSEL pin. If PORSEL is tied to GND, the DACs reset to zero-scale. If PORSEL is tied to VCC, the DACs reset to mid-scale. SPI DATA FORMAT (MSB First): 24-Bit Load Sequence: Byte #1 Byte #2 Byte #3 Command MSB LSB LTC2636-12 : C3 C2 C1 C0 A3 A2 A1 A0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X LTC2636-10 : C3 C2 C1 C0 A3 A2 A1 A0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X LTC2636-8 : C3 C2 C1 C0 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X X X 32-Bit Load Sequence: Byte #1 Byte #2 Byte #3 Byte #4 Command MSB LSB LTC2636-12 : X X X X X X X X C3 C2 C1 C0 A3 A2 A1 A0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X LTC2636-10 : X X X X X X X X C3 C2 C1 C0 A3 A2 A1 A0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X LTC2636-8 : X X X X X X X X C3 C2 C1 C0 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X X X Cx : DAC Command Code Ax : DAC Address (0=DACA, 1=DACB, 2=DACC, 3=DACD, 4=DACE, 5=DACF, 6=DACG, 7=DACH, 0xFF=All DACs) Dx : DAC Data Bits X : Don't care Example Code: Set DAC A to 2V for 16-bit DAC. shift_count = 0; // 16-bit DAC does not have to be shifted dac_voltage = 2.0; // Sets dac voltage variable to 2v dac_code = LTC2636_voltage_to_code(dac_voltage, LTC2636_lsb, LTC2636_offset); // Calculate DAC code from voltage, lsb, and offset LTC2636_write(LTC2636_CS, LTC2636_CMD_WRITE_UPDATE, LTC2636_DAC_A, dac_code << shift_count); // Set DAC A with DAC code
http://www.linear.com/product/LTC2636
http://www.linear.com/product/LTC2634
http://www.linear.com/product/LTC2636#demoboards
http://www.linear.com/product/LTC2634#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:
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 LTC2636 Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference.
Definition in file LTC2636.h.
Go to the source code of this file.
Functions | |
void | LTC2636_write (uint8_t cs, uint8_t dac_command, uint8_t dac_address, uint16_t dac_code) |
Write the 16-bit dac_code to the LTC2636. More... | |
uint16_t | LTC2636_voltage_to_code (float dac_voltage, float LTC2636_lsb, int16_t LTC2636_offset) |
Calculate a LTC2636 DAC code given the desired output voltage, offset, and LSB value. More... | |
float | LTC2636_code_to_voltage (uint16_t dac_code, float LTC2636_lsb, int16_t LTC2636_offset) |
Calculate the LTC2636 DAC output voltage given the DAC code, offset, and LSB value. More... | |
void | LTC2636_calibrate (uint16_t dac_code1, uint16_t dac_code2, float voltage1, float voltage2, float *LTC2636_lsb, int16_t *LTC2636_offset) |
Calculate the LTC2636 offset and LSB voltages given two measured voltages and their corresponding codes. More... | |
Macros | |
#define | LTC2636_CS QUIKEVAL_CS |
Define the SPI CS pin. More... | |
LTC2636 Command Codes | |
OR'd together with the DAC address to form the command byte | |
#define | LTC2636_CMD_WRITE 0x00 |
Write to input register n. More... | |
#define | LTC2636_CMD_UPDATE 0x10 |
Update (power up) DAC register n. More... | |
#define | LTC2636_CMD_WRITE_UPDATE_ALL 0x20 |
Write to input register n, update (power up) all. More... | |
#define | LTC2636_CMD_WRITE_UPDATE 0x30 |
Write to input register n, update (power up) all. More... | |
#define | LTC2636_CMD_POWER_DOWN 0x40 |
Power down n. More... | |
#define | LTC2636_CMD_POWER_DOWN_ALL 0x50 |
Power down chip (all DACs and reference) More... | |
#define | LTC2636_CMD_INTERNAL_REFERENCE 0x60 |
Select internal reference (power up reference) More... | |
#define | LTC2636_CMD_EXTERNAL_REFERENCE 0x70 |
Select external reference (power down internal reference) More... | |
#define | LTC2636_CMD_NO_OPERATION 0xF0 |
No operation. More... | |
LTC2636 DAC addresses | |
Which DAC to operate on | |
#define | LTC2636_DAC_A 0x00 |
#define | LTC2636_DAC_B 0x01 |
#define | LTC2636_DAC_C 0x02 |
#define | LTC2636_DAC_D 0x03 |
#define | LTC2636_DAC_E 0x04 |
#define | LTC2636_DAC_F 0x05 |
#define | LTC2636_DAC_G 0x06 |
#define | LTC2636_DAC_H 0x07 |
#define | LTC2636_DAC_ALL 0x0F |
void LTC2636_calibrate | ( | uint16_t | dac_code1, |
uint16_t | dac_code2, | ||
float | voltage1, | ||
float | voltage2, | ||
float * | LTC2636_lsb, | ||
int16_t * | LTC2636_offset | ||
) |
Calculate the LTC2636 offset and LSB voltages given two measured voltages and their corresponding codes.
dac_code1 | First DAC code |
dac_code2 | Second DAC code |
voltage1 | First voltage |
voltage2 | Second voltage |
LTC2636_lsb | Returns resulting LSB (volts) |
LTC2636_offset | Returns resulting Offset (volts) |
Definition at line 120 of file LTC2636.cpp.
float LTC2636_code_to_voltage | ( | uint16_t | dac_code, |
float | LTC2636_lsb, | ||
int16_t | LTC2636_offset | ||
) |
Calculate the LTC2636 DAC output voltage given the DAC code, offset, and LSB value.
dac_code | DAC code |
LTC2636_lsb | LSB value (volts) |
LTC2636_offset | Offset (volts) |
Definition at line 112 of file LTC2636.cpp.
uint16_t LTC2636_voltage_to_code | ( | float | dac_voltage, |
float | LTC2636_lsb, | ||
int16_t | LTC2636_offset | ||
) |
Calculate a LTC2636 DAC code given the desired output voltage, offset, and LSB value.
dac_voltage | Voltage to send to DAC |
LTC2636_lsb | LSB value (volts) |
LTC2636_offset | Offset (volts) |
Definition at line 99 of file LTC2636.cpp.
void LTC2636_write | ( | uint8_t | cs, |
uint8_t | dac_command, | ||
uint8_t | dac_address, | ||
uint16_t | dac_code | ||
) |
Write the 16-bit dac_code to the LTC2636.
cs | Chip Select Pin |
dac_command | Command Nibble, left-justified, lower nibble set to zero |
dac_address | DAC Address Nibble, right justified, upper nibble set to zero |
dac_code | 16-bit DAC code |
Definition at line 84 of file LTC2636.cpp.
#define LTC2636_CMD_EXTERNAL_REFERENCE 0x70 |
#define LTC2636_CMD_INTERNAL_REFERENCE 0x60 |
#define LTC2636_CMD_POWER_DOWN_ALL 0x50 |
#define LTC2636_CMD_UPDATE 0x10 |
#define LTC2636_CMD_WRITE_UPDATE 0x30 |
#define LTC2636_CMD_WRITE_UPDATE_ALL 0x20 |
#define LTC2636_CS QUIKEVAL_CS |