| Linduino 1.3.0 Linear Technology Arduino-Compatible Demonstration Board

LTC2655.h
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1 /*!
2 LTC2655: Quad I2C 16-/12-Bit Rail-to-Rail DACs with 10ppm/C Max Reference
3
4 @verbatim
5
6 The LTC2655 is a family of Quad I2C 16-/12-Bit Rail-to-Rail DACs with
7 integrated 10ppm/C max reference. The DACs have built-in high performance,
8 rail-to-rail, output buffers and are guaranteed monotonic. The LTC2655-L has a
9 full-scale output of 2.5V with the integrated reference and operates from a
10 single 2.7V to 5.5V supply. The LTC2655-H has a full-scale output of 4.096V with
11 the integrated reference and operates from a 4.5V to 5.5V supply. Each DAC can
12 also operate with an external reference, which sets the full-scale output to 2
13 times the external reference voltage.
14
15 The parts use the 2-wire I2C compatible serial interface. The LTC2655 operates
16 in both the standard mode (maximum clock rate of 100kHz) and the fast mode
17 (maximum clock rate of 400kHz). The LTC2655 incorporates a power-on reset
18 circuit that is controlled by the PORSEL pin. If PORSEL is tied to GND the DACs
19 power-on reset to zero-scale. If PORSEL is tied to VCC, the DACs power-on reset
20 to mid-scale.
21
22 I2C DATA FORMAT (MSB First):
23
24 Byte #1 Byte #2
25 MSB
26 LTC2655-16 : START SA6 SA5 SA4 SA3 SA2 SA1 SA0 W SACK C3 C2 C1 C0 A3 A2 A1 A0 SACK
27 LTC2655-12 : START SA6 SA5 SA4 SA3 SA2 SA1 SA0 W SACK C3 C2 C1 C0 A3 A2 A1 A0 SACK
28
29
30 Byte #3 Byte #4
31 LSB
32 D15 D14 D13 D12 D11 D10 D9 D8 SACK D7 D6 D5 D4 D3 D2 D1 D0 SACK STOP
33 D11 D10 D9 D8 D7 D6 D5 D4 SACK D3 D2 D1 D0 X X X X SACK STOP
34
35 START: I2C Start
36 SAx : I2C Address
37 W : I2C Write (0)
38 SACK : I2C Slave Generated Acknowledge (Active Low)
39 Cx : DAC Command Code
40 Ax : DAC Address (0=DACA, 1=DACB, 2=DACC, 3=DACD, 0xFF=All DACs)
41 Dx : DAC Data Bits
42 X : Don't care
43 STOP : I2C Stop
44
45
46 Example Code:
47
48 Set DAC A to to 2V for 16-bit DAC.
49
50 shift_count = 0; // 16-bit DAC does not have to be shifted
51 dac_voltage = 2.0; // Sets dac voltage variable to 2v
52
53 dac_code = LTC2655_voltage_to_code(dac_voltage, LTC2655_lsb, LTC2655_offset); // Calculate DAC code from voltage, lsb, and offset
54 ack = LTC2655_write(LTC2655_I2C_ADDRESS, LTC2655_CMD_WRITE_UPDATE, LTC2655_DAC_A, dac_code); // Set DAC A with DAC code
55 @endverbatim
56
57 http://www.linear.com/product/LTC2655
58
59 http://www.linear.com/product/LTC2655#demoboards
60
61
62 Copyright 2018(c) Analog Devices, Inc.
63
64 All rights reserved.
65
66 Redistribution and use in source and binary forms, with or without
67 modification, are permitted provided that the following conditions are met:
68 - Redistributions of source code must retain the above copyright
69 notice, this list of conditions and the following disclaimer.
70 - Redistributions in binary form must reproduce the above copyright
71 notice, this list of conditions and the following disclaimer in
72 the documentation and/or other materials provided with the
73 distribution.
74 - Neither the name of Analog Devices, Inc. nor the names of its
75 contributors may be used to endorse or promote products derived
76 from this software without specific prior written permission.
77 - The use of this software may or may not infringe the patent rights
78 of one or more patent holders. This license does not release you
79 from the requirement that you obtain separate licenses from these
80 patent holders to use this software.
81 - Use of the software either in source or binary form, must be run
82 on or directly connected to an Analog Devices Inc. component.
83
84 THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
85 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
86 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
87 IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
88 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
89 LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
90 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
91 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
92 OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
93 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
94 */
95
96 /*! @file
97 @ingroup LTC2655
98 Header for LTC2655: Quad I2C 16-/12-Bit Rail-to-Rail DACs with 10ppm/C Max Reference
99 */
100
101 #ifndef LTC2655_H
102 #define LTC2655_H
103
104 #include <Wire.h>
105
106 //! @name I2C_Addresses
107 //!@{
108 // I2C Address Choices:
109 // To choose an address, comment out all options except the
110 // configuration on the demo board.
111
112 // Address assignment
113 // LTC2655 I2C Address // AD2 AD1 AD0
114 #define LTC2655_I2C_ADDRESS 0x10 // GND GND GND
115 // #define LTC2655_I2C_ADDRESS 0x11 // GND GND Float
116 // #define LTC2655_I2C_ADDRESS 0x12 // GND GND Vcc
117 // #define LTC2655_I2C_ADDRESS 0x13 // GND Float GND
118 // #define LTC2655_I2C_ADDRESS 0x20 // GND Float Float
119 // #define LTC2655_I2C_ADDRESS 0x21 // GND Float Vcc
120 // #define LTC2655_I2C_ADDRESS 0x22 // GND Vcc GND
121 // #define LTC2655_I2C_ADDRESS 0x23 // GND Vcc Float
122 // #define LTC2655_I2C_ADDRESS 0x30 // GND Vcc Vcc
123 // #define LTC2655_I2C_ADDRESS 0x31 // Float GND GND
124 // #define LTC2655_I2C_ADDRESS 0x32 // Float GND Float
125 // #define LTC2655_I2C_ADDRESS 0x33 // Float GND Vcc
126 // #define LTC2655_I2C_ADDRESS 0x40 // Float Float GND
127 // #define LTC2655_I2C_ADDRESS 0x41 // Float Float Float
128 // #define LTC2655_I2C_ADDRESS 0x42 // Float Float Vcc
129 // #define LTC2655_I2C_ADDRESS 0x43 // Float Vcc GND
130 // #define LTC2655_I2C_ADDRESS 0x50 // Float Vcc Float
131 // #define LTC2655_I2C_ADDRESS 0x51 // Float Vcc Vcc
132 // #define LTC2655_I2C_ADDRESS 0x52 // Vcc GND GND
133 // #define LTC2655_I2C_ADDRESS 0x53 // Vcc GND Float
134 // #define LTC2655_I2C_ADDRESS 0x60 // Vcc GND Vcc
135 // #define LTC2655_I2C_ADDRESS 0x61 // Vcc Float GND
136 // #define LTC2655_I2C_ADDRESS 0x62 // Vcc Float Float
137 // #define LTC2655_I2C_ADDRESS 0x63 // Vcc Float Vcc
138 // #define LTC2655_I2C_ADDRESS 0x70 // Vcc Vcc GND
139 // #define LTC2655_I2C_ADDRESS 0x71 // Vcc Vcc Float
140 // #define LTC2655_I2C_ADDRESS 0x72 // Vcc Vcc Vcc
141
142 #define LTC2655_I2C_GLOBAL_ADDRESS 0x73
143 //! @}
144
145 //! @name LTC2655 Command Codes
146 //! @{
147 //! OR'd together with the DAC address to form the command byte
148 #define LTC2655_CMD_WRITE 0x00 // Write to input register n
149 #define LTC2655_CMD_UPDATE 0x10 // Update (power up) DAC register n
150 #define LTC2655_CMD_WRITE_UPDATE 0x30 // Write to input register n, update (power up) all
151 #define LTC2655_CMD_POWER_DOWN 0x40 // Power down n
152 #define LTC2655_CMD_POWER_DOWN_ALL 0x50 // Power down chip (all DACs and reference)
153 #define LTC2655_CMD_INTERNAL_REFERENCE 0x60 // Select internal reference (power up reference)
154 #define LTC2655_CMD_EXTERNAL_REFERENCE 0x70 // Select external reference (power down internal reference)
155 #define LTC2655_CMD_NO_OPERATION 0xF0 // No operation
156 //! @}
157
158 //! @name LTC2655 DAC Addresses
159 //! @{
160 //! Which DAC to operate on
161 #define LTC2655_DAC_A 0x00
162 #define LTC2655_DAC_B 0x01
163 #define LTC2655_DAC_C 0x02
164 #define LTC2655_DAC_D 0x03
165 #define LTC2655_DAC_ALL 0x0F
166 //! @}
167
168 // Command Example - write to DAC address D and update all.
169 // dac_command = LTC2655_CMD_WRITE_UPDATE | LTC2655_DAC_D;
170
171 //! Write a 16-bit dac_code to the LTC2655.
172 //! @return ACK bit (0=acknowledge, 1=no acknowledge)
173 int8_t LTC2655_write(uint8_t i2c_address, //!< I2C address of DAC
174 uint8_t dac_command, //!< Command Nibble, left-justified, lower nibble set to zero
175 uint8_t dac_address, //!< DAC Address Nibble, right justified, upper nibble set to zero
176 uint16_t dac_code //!< 16-bit DAC code
177 );
178
179 //! Calculate a LTC2655 DAC code given the desired output voltage
180 //! @return The 16-bit code to send to the DAC
181 uint16_t LTC2655_voltage_to_code(float dac_voltage, //!< Voltage to send to DAC
182 float LTC2655_lsb, //!< LSB value
183 int16_t LTC2655_offset //!< Offset
184 );
185
186 //! Calculate the LTC2655 DAC output voltage given the DAC code, offset, and LSB value
187 //! @return Calculated voltage
188 float LTC2655_code_to_voltage(uint16_t dac_code, //!< DAC code
189 float LTC2655_lsb, //!< LSB value
190 int16_t LTC2655_offset //!< Offset
191 );
192
193 //! Calculate the LTC2655 offset and LSB voltages given two measured voltages and their corresponding codes
194 //! @return Void
195 void LTC2655_calibrate(uint16_t dac_code1, //!< First DAC code
196 uint16_t dac_code2, //!< Second DAC code
197 float voltage1, //!< First voltage
198 float voltage2, //!< Second voltage
199 float *LTC2655_lsb, //!< Returns resulting LSB
200 int16_t *LTC2655_offset //!< Returns resulting Offset
201 );
202
203 #endif // LTC2655_H
LTC2655_calibrate
void LTC2655_calibrate(uint16_t dac_code1, uint16_t dac_code2, float voltage1, float voltage2, float *LTC2655_lsb, int16_t *LTC2655_offset)
Calculate the LTC2655 offset and LSB voltages given two measured voltages and their corresponding cod...
Definition: LTC2655.cpp:112
i2c_address
uint8_t i2c_address
LTC2655_lsb
static float LTC2655_lsb[5]
The LTC2655 lsb - index 4 for "all DACs." If part is calibrated, then index 0 is stored to "all DACs...
Definition: DC1703A.ino:167
LTC2655_write
int8_t LTC2655_write(uint8_t i2c_address, uint8_t dac_command, uint8_t dac_address, uint16_t dac_code)
Write a 16-bit dac_code to the LTC2655.
Definition: LTC2655.cpp:82
LTC2655_voltage_to_code
uint16_t LTC2655_voltage_to_code(float dac_voltage, float LTC2655_lsb, int16_t LTC2655_offset)
Calculate a LTC2655 DAC code given the desired output voltage.
Definition: LTC2655.cpp:91
LTC2655_offset
static int16_t LTC2655_offset[5]
DAC offset - index 4 for "all DACs." If part is calibrated, then index 0 is stored to "all DACs...
Definition: DC1703A.ino:166
LTC2655_code_to_voltage
float LTC2655_code_to_voltage(uint16_t dac_code, float LTC2655_lsb, int16_t LTC2655_offset)
Calculate the LTC2655 DAC output voltage given the DAC code, offset, and LSB value.
Definition: LTC2655.cpp:104