SMART ARM-based Microcontrollers
AT10799: SAM Operational Amplifier Controller
(OPAMP) Driver
APPLICATION NOTE
Introduction
®
®
This driver for Atmel | SMART ARM -based microcontrollers provides an
interface for the configuration and management of the device's Operational
Amplifier Controller functionality.
The following peripheral is used by this module:
•
OPAMP (Operational Amplifier Controller)
The following devices can use this module:
•
Atmel | SMART SAM L21
The outline of this documentation is as follows:
•
Prerequisites
•
Module Overview
•
Special Considerations
•
Extra Information
•
Examples
•
API Overview
Atmel-42446A-SAM-Operational-Amplifier-Controller-OPAMP-Driver_AT10799_Application Note-07/2015
Table of Contents
Introduction......................................................................................................................1
1. Software License....................................................................................................... 4
2. Prerequisites..............................................................................................................5
3. Module Overview....................................................................................................... 6
4. Special Considerations.............................................................................................. 7
5. Extra Information....................................................................................................... 8
6. Examples................................................................................................................... 9
7. API Overview........................................................................................................... 10
7.1.
7.2.
Structure Definitions................................................................................................................... 10
7.1.1.
Struct opamp0_config..................................................................................................10
7.1.2.
Struct opamp1_config..................................................................................................10
7.1.3.
Struct opamp2_config..................................................................................................10
7.1.4.
Struct opamp_config_common.................................................................................... 11
Function Definitions.................................................................................................................... 11
7.2.1.
Function opamp0_get_config_defaults()......................................................................11
7.2.2.
Function opamp0_set_config().................................................................................... 12
7.2.3.
Function opamp1_get_config_defaults()..................................................................... 12
7.2.4.
Function opamp1_set_config().................................................................................... 12
7.2.5.
Function opamp2_get_config_defaults()..................................................................... 12
7.2.6.
Function opamp2_set_config().................................................................................... 13
7.2.7.
Function opamp_disable()........................................................................................... 13
7.2.8.
Function opamp_enable()............................................................................................13
7.2.9.
Function opamp_is_ready()......................................................................................... 14
7.2.10. Function opamp_module_disable()............................................................................. 14
7.2.11.
7.2.12.
7.2.13.
7.2.14.
7.2.15.
7.3.
Function opamp_module_enable().............................................................................. 14
Function opamp_module_init().................................................................................... 14
Function opamp_module_reset().................................................................................14
Function opamp_voltage_doubler_disable()................................................................15
Function opamp_voltage_doubler_enable()................................................................ 15
Enumeration Definitions............................................................................................................. 15
7.3.1.
Enum opamp0_neg_mux.............................................................................................15
7.3.2.
Enum opamp0_pos_mux.............................................................................................15
7.3.3.
Enum opamp0_res1_mux............................................................................................15
7.3.4.
Enum opamp1_neg_mux.............................................................................................16
7.3.5.
Enum opamp1_pos_mux.............................................................................................16
7.3.6.
Enum opamp1_res1_mux............................................................................................16
7.3.7.
Enum opamp2_neg_mux.............................................................................................17
7.3.8.
Enum opamp2_pos_mux.............................................................................................17
7.3.9.
Enum opamp2_res1_mux............................................................................................17
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7.3.10.
Enum opamp_bias_selection.......................................................................................18
7.3.11.
7.3.12.
Enum opamp_id...........................................................................................................18
Enum opamp_pot_mux................................................................................................18
8. Extra Information for OPAMP Driver........................................................................19
8.1.
8.2.
8.3.
8.4.
Acronyms....................................................................................................................................19
Dependencies.............................................................................................................................19
Errata..........................................................................................................................................19
Module History............................................................................................................................19
9. Examples for OPAMP Driver................................................................................... 20
9.1.
Quick Start Guide for OPAMP - Basic........................................................................................ 20
9.1.1.
Setup........................................................................................................................... 20
9.1.2.
Use Case..................................................................................................................... 22
10. Document Revision History..................................................................................... 23
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1.
Software License
Redistribution and use in source and binary forms, with or without modification, are permitted provided
that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
following disclaimer.
2. 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.
3. The name of Atmel may not be used to endorse or promote products derived from this software without
specific prior written permission.
4. This software may only be redistributed and used in connection with an Atmel microcontroller product.
THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE EXPRESSLY AND SPECIFICALLY
DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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.
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2.
Prerequisites
There are no prerequisites for this module.
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3.
Module Overview
The OPAMP is an individually configurable low power, general purpose operational amplifier offering a
high degree of flexibility and rail-to-rail inputs.
Each operational amplifier can be configured in standalone operational amplifier and operational amplifier
with built-in feedback. All OPAMPs can be cascaded to support circuits such as differential amplifiers.
Note: For more detail configuration reference, refer to the "Built-in Modes" section in the device
datasheet.
Each OPAMP has one positive and one negative input which can be flexible chosen from analog input
pins including the output of another OPAMP, internal inputs such as the DAC or the resistor ladder, and
the ground.
Each OPAMP output can be selected as input for AC or ADC, also available on I/O pins.
Four modes are available to select the trade-off between speed and power consumption to best fit the
application requirements and optimize the power consumption.
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4.
Special Considerations
There are no special considerations for this module.
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5.
Extra Information
For extra information, see Extra Information for OPAMP Driver. This includes:
•
Acronyms
•
Dependencies
•
Errata
•
Module History
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6.
Examples
For a list of examples related to this driver, see Examples for OPAMP Driver.
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7.
API Overview
7.1.
Structure Definitions
7.1.1.
Struct opamp0_config
Configuration structure for OPAMP 0.
Table 7-1 Members
Type
Name
Description
struct opamp_config_common config_common If true, the comparator will continue to sample during
sleep mode when triggered
7.1.2.
enum opamp0_neg_mux
negative_input
Negative input MUX selection
enum opamp0_pos_mux
positive_input
Positive input MUX selection
enum opamp0_res1_mux
r1_connection
Resistor 1 MUX selection
Struct opamp1_config
Configuration structure for OPAMP 1.
Table 7-2 Members
Type
Name
Description
struct opamp_config_common config_common If true, the comparator will continue to sample during
sleep mode when triggered
7.1.3.
enum opamp1_neg_mux
negative_input
Negative input MUX selection
enum opamp1_pos_mux
positive_input
Positive input MUX selection
enum opamp1_res1_mux
r1_connection
Resistor 1 MUX selection
Struct opamp2_config
Configuration structure for OPAMP 2.
Table 7-3 Members
Type
Name
Description
struct opamp_config_common config_common If true, the comparator will continue to sample during
sleep mode when triggered
enum opamp2_neg_mux
negative_input
Negative input MUX selection
enum opamp2_pos_mux
positive_input
Positive input MUX selection
enum opamp2_res1_mux
r1_connection
Resistor 1 MUX selection
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7.1.4.
Struct opamp_config_common
Common configuration structure for OPAMP 0 to 2.
Table 7-4 Members
Type
Name
Description
bool
analog_out
If true, OPAMP output is connected to the ADC
or AC input
enum
opamp_bias_selection
bias_value
Bias mode selection
bool
on_demand
If true, the OPAMPx is enabled when a
peripheral is requesting the OPAMPx to be used
as an input. The OPAMPx is disabled if no
peripheral is requesting it as an input.
enum opamp_pot_mux
potentiometer_selection Potentiometer selection
bool
r1_enable
If true, R1 connected to RES1MUX
bool
r2_out
If true, resistor ladder to output
bool
r2_vcc
If true, resistor ladder to VCC
bool
run_in_standby
If true, the OPAMPx is not stopped during
sleep mode when triggered
7.2.
Function Definitions
7.2.1.
Function opamp0_get_config_defaults()
Initializes all members of OPAMP0 configuration structure to safe defaults.
void opamp0_get_config_defaults(
struct opamp0_config *const config)
Initializes all members of OPAMP0 configuration structure to safe defaults. This function should be called
on all new instances of these configuration structures before being modified by the user application.
The default configuration is setting OPAMP0 as "Voltage Follower", refer to the first mode of "Built-in
Modes" in the device datasheet.
Table 7-5 Parameters
Data direction
Parameter name
Description
[out]
config
OPAMP0 configuration structure to initialize to default values
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7.2.2.
Function opamp0_set_config()
Writes OPAMP0 configuration to the hardware module.
void opamp0_set_config(
struct opamp0_config *const config)
Writes a given OPAMP0 configuration to the hardware module.
Table 7-6 Parameters
7.2.3.
Data direction
Parameter name
Description
[in]
config
Pointer to the OPAMP0 configuration struct
Function opamp1_get_config_defaults()
Initializes all members of OPAMP1 configuration structure to safe defaults.
void opamp1_get_config_defaults(
struct opamp1_config *const config)
Initializes all members of OPAMP1 configuration structure to safe defaults. This function should be called
on all new instances of these configuration structures before being modified by the user application.
The default configuration is setting OPAMP1 as "Voltage Follower", refer to the first mode of "Built-in
Modes" in the device datasheet.
Table 7-7 Parameters
7.2.4.
Data direction
Parameter name
Description
[out]
config
OPAMP1 configuration structure to initialize to default values
Function opamp1_set_config()
Writes OPAMP1 configuration to the hardware module.
void opamp1_set_config(
struct opamp1_config *const config)
Writes a given OPAMP1 configuration to the hardware module.
Table 7-8 Parameters
7.2.5.
Data direction
Parameter name
Description
[in]
config
Pointer to the OPAMP1 configuration struct
Function opamp2_get_config_defaults()
Initializes all members of OPAMP2 configuration structure to safe defaults.
void opamp2_get_config_defaults(
struct opamp2_config *const config)
Initializes all members of OPAMP2 configuration structure to safe defaults. This function should be called
on all new instances of these configuration structures before being modified by the user application.
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The default configuration is setting OPAMP2 as "Voltage Follower", refer to the first mode of "Built-in
Modes" in the device datasheet.
Table 7-9 Parameters
7.2.6.
Data direction
Parameter name
Description
[out]
config
OPAMP2 configuration structure to initialize to default values
Function opamp2_set_config()
Writes OPAMP2 configuration to the hardware module.
void opamp2_set_config(
struct opamp2_config *const config)
Writes a given OPAMP2 configuration to the hardware module.
Table 7-10 Parameters
7.2.7.
Data direction
Parameter name
Description
[in]
config
Pointer to the OPAMP2 configuration struct
Function opamp_disable()
Disables an OPAMP that was previously enabled.
void opamp_disable(
const enum opamp_id number)
Disables an OPAMP that was previously enabled via a call to opamp_enable().
Table 7-11 Parameters
7.2.8.
Data direction
Parameter name
Description
[in]
number
OPAMP number to disable
Function opamp_enable()
Enables an OPAMP that was previously configured.
void opamp_enable(
const enum opamp_id number)
Enables an OPAMP that was previously configured via a call to the set configuration function.
Table 7-12 Parameters
Data direction
Parameter name
Description
[in]
number
OPAMP number to enable
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7.2.9.
Function opamp_is_ready()
Checks an OPAMP output ready status.
bool opamp_is_ready(
const enum opamp_id number)
Checks if an OPAMP output is ready.
Table 7-13 Parameters
Data direction
Parameter name
Description
[in]
number
OPAMP number to check
Returns
Ready status of the select OPAMP.
Table 7-14 Return Values
7.2.10.
Return value
Description
false
If the select OPAMP output is not ready
ture
If the select OPAMP output is ready
Function opamp_module_disable()
Disables OPAMP module.
void opamp_module_disable( void )
Disables the peripheral.
7.2.11.
Function opamp_module_enable()
Enables OPAMP module.
void opamp_module_enable( void )
Enable the peripheral. Each OPAMP must also be enabled individually by the Enable bit in the
corresponding OPAMP Control register.
7.2.12.
Function opamp_module_init()
Initializes OPAMP module.
void opamp_module_init( void )
Resets all registers in the MODULE to their initial state, and then enable the module.
7.2.13.
Function opamp_module_reset()
Resets OPAMP module.
void opamp_module_reset( void )
Resets all registers in the MODULE to their initial state, and the OPAMP will be disabled.
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7.2.14.
Function opamp_voltage_doubler_disable()
Disables OPAMP voltage doubler.
void opamp_voltage_doubler_disable( void )
The analog input MUXes have high resistance, but consume less power at lower voltages (e.g., the
voltage doubler is disabled).
7.2.15.
Function opamp_voltage_doubler_enable()
Enables OPAMP voltage doubler.
void opamp_voltage_doubler_enable( void )
The analog input MUXes have low resistance, but consume more power at lower voltages (e.g., driven by
the voltage doubler).
7.3.
Enumeration Definitions
7.3.1.
Enum opamp0_neg_mux
Enum for the negative input of OPAMP0.
Table 7-15 Members
7.3.2.
Enum value
Description
OPAMP0_NEG_MUX_PIN0
Negative I/O pin 0
OPAMP0_NEG_MUX_TAP0
Resistor ladder 0 taps
OPAMP0_NEG_MUX_OUT0
OPAMP output
OPAMP0_NEG_MUX_DAC
DAC output
Enum opamp0_pos_mux
Enum for the positive input of OPAMP0.
Table 7-16 Members
7.3.3.
Enum value
Description
OPAMP0_POS_MUX_PIN0
Positive I/O pin 0
OPAMP0_POS_MUX_TAP0
Resistor ladder 0 taps
OPAMP0_POS_MUX_DAC
DAC output
OPAMP0_POS_MUX_GND
Ground
Enum opamp0_res1_mux
Enum for the Resistor 1 of OPAMP0.
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Table 7-17 Members
7.3.4.
Enum value
Description
OPAMP0_RES1_MUX_POS_PIN0
Positive input of OPAMP0
OPAMP0_RES1_MUX_NEG_PIN0
Negative input of OPAMP0
OPAMP0_RES1_MUX_DAC
DAC output
OPAMP0_RES1_MUX_GND
Ground
Enum opamp1_neg_mux
Enum for the negative input of OPAMP1.
Table 7-18 Members
7.3.5.
Enum value
Description
OPAMP1_NEG_MUX_PIN1
Negative I/O pin 1
OPAMP1_NEG_MUX_TAP1
Resistor ladder 1 taps
OPAMP1_NEG_MUX_OUT1
OPAMP output
OPAMP1_NEG_MUX_DAC
DAC output
Enum opamp1_pos_mux
Enum for the positive input of OPAMP1.
Table 7-19 Members
7.3.6.
Enum value
Description
OPAMP1_POS_MUX_PIN1
Positive I/O pin 1
OPAMP1_POS_MUX_TAP1
Resistor ladder 1 taps
OPAMP1_POS_MUX_OUT0
OPAMP0 output
OPAMP1_POS_MUX_GND
Ground
Enum opamp1_res1_mux
Enum for the Resistor 1 of OPAMP1.
Table 7-20 Members
Enum value
Description
OPAMP1_RES1_MUX_POS_PIN0
Positive input of OPAMP1
OPAMP1_RES1_MUX_NEG_PIN0
Negative input of OPAMP1
OPAMP1_RES1_MUX_OUT0
OPAMP0 output
OPAMP1_RES1_MUX_GND
Ground
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7.3.7.
Enum opamp2_neg_mux
Enum for the negative input of OPAMP2.
Table 7-21 Members
7.3.8.
Enum value
Description
OPAMP2_NEG_MUX_PIN2
Negative I/O pin 2
OPAMP2_NEG_MUX_TAP2
Resistor ladder 2 taps
OPAMP2_NEG_MUX_OUT2
OPAMP output
OPAMP2_NEG_MUX_PIN0
Negative I/O pin 0
OPAMP2_NEG_MUX_PIN1
Negative I/O pin 1
OPAMP2_NEG_MUX_DAC
DAC output
Enum opamp2_pos_mux
Enum for the positive input of OPAMP2.
Table 7-22 Members
7.3.9.
Enum value
Description
OPAMP2_POS_MUX_PIN2
Positive I/O pin 2
OPAMP2_POS_MUX_TAP2
Resistor ladder 2 taps
OPAMP2_POS_MUX_OUT1
OPAMP1 output
OPAMP2_POS_MUX_GND
Ground
OPAMP2_POS_MUX_PIN0
Positive I/O pin 0
OPAMP2_POS_MUX_PIN1
Positive I/O pin 1
OPAMP2_POS_MUX_TAP0
Resistor ladder 0 taps
Enum opamp2_res1_mux
Enum for the Resistor 1 of OPAMP2.
Table 7-23 Members
Enum value
Description
OPAMP2_RES1_MUX_POS_PIN0
Positive input of OPAMP2
OPAMP2_RES1_MUX_NEG_PIN0
Negative input of OPAMP2
OPAMP2_RES1_MUX_OUT1
OPAMP1 output
OPAMP2_RES1_MUX_GND
Ground
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7.3.10.
Enum opamp_bias_selection
Enum for the Bias mode selection of OPAMP 0 to 2.
Table 7-24 Members
7.3.11.
Enum value
Description
OPAMP_BIAS_MODE_0
Minimum current consumption but the slowest mode
OPAMP_BIAS_MODE_1
Low current consumption, slow speed
OPAMP_BIAS_MODE_2
High current consumption, fast speed
OPAMP_BIAS_MODE_3
Maximum current consumption but the fastest mode
Enum opamp_id
Table 7-25 Members
7.3.12.
Enum value
Description
OPAMP_0
OPAMP 0
OPAMP_1
OPAMP 1
OPAMP_2
OPAMP 2
OPAMP_NUM
OPAMP number
Enum opamp_pot_mux
Enum for the potentiometer selection of OPAMP 0 to 2.
Table 7-26 Members
Enum value
Description
OPAMP_POT_MUX_14R_2R
Gain = R2/R1 = 1/7
OPAMP_POT_MUX_12R_4R
Gain = R2/R1 = 1/3
OPAMP_POT_MUX_8R_8R
Gain = R2/R1 = 1
OPAMP_POT_MUX_6R_10R
Gain = R2/R1 = 1 + 2/3
OPAMP_POT_MUX_4R_12R
Gain = R2/R1 = 3
OPAMP_POT_MUX_3R_13R
Gain = R2/R1 = 4 + 1/3
OPAMP_POT_MUX_2R_14R
Gain = R2/R1 = 7
OPAMP_POT_MUX_R_15R
Gain = R2/R1 = 15
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8.
Extra Information for OPAMP Driver
8.1.
Acronyms
Below is a table listing the acronyms used in this module, along with their intended meanings.
8.2.
Acronym
Description
OPAMP
Operational Amplifier Controller
Dependencies
This driver has no dependencies.
8.3.
Errata
There are no errata related to this driver.
8.4.
Module History
An overview of the module history is presented in the table below, with details on the enhancements and
fixes made to the module since its first release. The current version of this corresponds to the newest
version in the table.
Changelog
Initial Release
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9.
Examples for OPAMP Driver
This is a list of the available Quick Start guides (QSGs) and example applications for SAM Operational
Amplifier Controller (OPAMP) Driver. QSGs are simple examples with step-by-step instructions to
configure and use this driver in a selection of use cases. Note that a QSG can be compiled as a
standalone application or be added to the user application.
•
9.1.
Quick Start Guide for OPAMP - Basic
Quick Start Guide for OPAMP - Basic
In this use case, the OPAMP0 is configured as "Non-Inverting PGA" mode, refer to the second mode of
"Built-in Modes" in the device datasheet.
This use case sets up the OPAMP0 to invert the input signal in OA0NEG pin, and output it to the
OA0OUT pin. You can give a signal on OA0NEG and watch the output on OA0OUT through an
oscilloscope.
9.1.1.
Setup
9.1.1.1.
Prerequisites
There are no special setup requirements for this use case.
9.1.1.2.
Code
Copy-paste the following setup code to your user application:
void configure_non_inverting_pga_opamp0(void)
{
struct opamp0_config conf;
opamp_module_init();
opamp0_get_config_defaults(&conf);
/* Set the the OPAMP0 as "Non-Inverting PGA" mode. */
conf.negative_input = OPAMP0_NEG_MUX_TAP0;
conf.positive_input = OPAMP0_POS_MUX_PIN0;
conf.r1_connection = OPAMP0_RES1_MUX_GND;
conf.config_common.r1_enable = true;
conf.config_common.r2_out = true;
/* Set up OA0NEG pin and OA0OUT pin. */
struct system_pinmux_config opamp0_neg_pin_conf;
system_pinmux_get_config_defaults(&opamp0_neg_pin_conf);
opamp0_neg_pin_conf.direction
= SYSTEM_PINMUX_PIN_DIR_INPUT;
opamp0_neg_pin_conf.mux_position = MUX_PA06B_OPAMP_OAPOS0;
system_pinmux_pin_set_config(PIN_PA06B_OPAMP_OAPOS0,
&opamp0_neg_pin_conf);
struct system_pinmux_config opamp0_out_pin_conf;
system_pinmux_get_config_defaults(&opamp0_out_pin_conf);
opamp0_out_pin_conf.direction
= SYSTEM_PINMUX_PIN_DIR_OUTPUT;
opamp0_out_pin_conf.mux_position = MUX_PA07B_OPAMP_OAOUT0;
system_pinmux_pin_set_config(PIN_PA07B_OPAMP_OAOUT0,
&opamp0_out_pin_conf);
opamp0_set_config(&conf);
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opamp_enable(OPAMP_0);
}
/* Wait for the output ready. */
while(!opamp_is_ready(OPAMP_0));
Add to user application initialization (typically the start of main()):
configure_non_inverting_pga_opamp0();
9.1.1.3.
Workflow
1.
Create an OPAMP0 configuration struct, which can be filled out to adjust the configuration of
OPAMP0.
struct opamp0_config conf;
2.
Initialize the OPAMP module.
opamp_module_init();
3.
Initialize the OPAMP0 configuration struct with the module's default values.
opamp0_get_config_defaults(&conf);
4.
Note: This should always be performed before using the configuration struct to ensure that all
values are initialized to known default settings.
Adjust the configuration struct to set the OPAMP0 as "Non-Inverting PGA" mode.
conf.negative_input = OPAMP0_NEG_MUX_TAP0;
conf.positive_input = OPAMP0_POS_MUX_PIN0;
conf.r1_connection = OPAMP0_RES1_MUX_GND;
conf.config_common.r1_enable = true;
conf.config_common.r2_out = true;
5.
Note: The existing configuration struct may be re-used, as long as any values that have been
altered from the default settings are taken into account by the user application.
Set up OA0NEG pin and OA0OUT pin.
struct system_pinmux_config opamp0_neg_pin_conf;
system_pinmux_get_config_defaults(&opamp0_neg_pin_conf);
opamp0_neg_pin_conf.direction
= SYSTEM_PINMUX_PIN_DIR_INPUT;
opamp0_neg_pin_conf.mux_position = MUX_PA06B_OPAMP_OAPOS0;
system_pinmux_pin_set_config(PIN_PA06B_OPAMP_OAPOS0,
&opamp0_neg_pin_conf);
struct system_pinmux_config opamp0_out_pin_conf;
system_pinmux_get_config_defaults(&opamp0_out_pin_conf);
opamp0_out_pin_conf.direction
= SYSTEM_PINMUX_PIN_DIR_OUTPUT;
opamp0_out_pin_conf.mux_position = MUX_PA07B_OPAMP_OAOUT0;
system_pinmux_pin_set_config(PIN_PA07B_OPAMP_OAOUT0,
&opamp0_out_pin_conf);
6.
Write OPAMP0 configuration to the hardware module.
opamp0_set_config(&conf);
7.
Enable OPAMP0.
opamp_enable(OPAMP_0);
8.
Wait for the output ready.
while(!opamp_is_ready(OPAMP_0));
Atmel AT10799: SAM Operational Amplifier Controller (OPAMP) Driver [APPLICATION
NOTE]
Atmel-42446A-SAM-Operational-Amplifier-Controller-OPAMP-Driver_AT10799_Application Note-07/2015
21
9.1.2.
Use Case
9.1.2.1.
Code
Copy-paste the following code to your user application:
while (true) {
/* Do nothing */
}
Atmel AT10799: SAM Operational Amplifier Controller (OPAMP) Driver [APPLICATION
NOTE]
Atmel-42446A-SAM-Operational-Amplifier-Controller-OPAMP-Driver_AT10799_Application Note-07/2015
22
10.
Document Revision History
Doc. Rev.
Date
Comments
42446A
07/2015
Initial document release
Atmel AT10799: SAM Operational Amplifier Controller (OPAMP) Driver [APPLICATION
NOTE]
Atmel-42446A-SAM-Operational-Amplifier-Controller-OPAMP-Driver_AT10799_Application Note-07/2015
23
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