Component - ILO Trim V1.0 Component Datasheet.pdf

®
PSoC Creator™ Component Datasheet
ILO Trim
1.0
Features
 Trims 1 kHz and 100 kHz ILO for PSoC 3 and PSoC 5LP
 ILO trimming support for PSoC 3 and PSoC 5LP
 UDB and Fixed-Function modes
 User-specified reference clock
General Description
The ILO Trim component allows your application to determine the accuracy of the ILO. It
provides a scaling function to allow the application to compensate for this inaccuracy. For
PSoC 3 and PSoC 5LP devices, it can also directly improve the accuracy of the ILO by using a
user-defined higher frequency, higher accuracy reference clock to count the number of ILO clock
cycles. The derived information is then used to trim the ILO trim registers to incrementally
approach the desired ILO frequency. The component supports both UDB and Fixed-Function
implementations.
trim100k[3:0]
Trim
DAC
coarseTrim[2:0]
Bias
trim1k[3:0]
Trim
DAC
100 kHz
LSO
100 kHz
Divide by
3
1 kHz
LSO
33 kHz
1 kHz
For PSoC 3 and PSoC 5LP, the ILO consists of two low-speed oscillators (LSO): 100 kHz and 1
kHz. These are used to generate ILO clock frequencies of 1 kHz, 33 kHz, or 100 kHz. Post
factory trim, the 1 kHz LSO has an accuracy of -50% to 100% and the 100 kHz LSO has an
accuracy of -55% to 100% over the entire operating range of voltage and temperature.
During the run-time trimming operation, the trim DACs and the bias block are adjusted using the
ILO Trim registers. For PSoC 4, the ILO is a 32 kHz low-frequency clock (LFCLK). Trimming for
PSoC 4 is not supported; however the user can use the scaling function to retrieve the
compensation information that can be used in their applications.
Cypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600
Document Number: 001-86907 Rev. **
Revised April 9, 2013
ILO Trim
®
PSoC Creator™ Component Datasheet
Note The performance of ILO Trim component is not fully characterized for PSoC 3 and
PSoC 5LP devices. For this reason, the component is displayed as ‘Prototype’ on the schematic
when placed on PSoC 3 and PSoC 5LP designs.
When to Use an ILO Trim
The ILO Trim component is used to achieve a higher accuracy ILO clock. One use of the
component is to use it to trim the ILO, which will then be used as a clock in sleep mode. In such
an instance, a more accurate ILO allows for more precise event timing. Alternatively, the
compensation function can be used to retrieve the inaccuracy compensation information, which
can then be used in the user’s application (such as a watchdog timer).
Input/Output Connections
This section describes the input and output connections for the ILO Trim component.
ref_clk
This terminal is the clock signal used as the timing reference for counting the ILO period.
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Document Number: 001-86907 Rev. **
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PSoC Creator™ Component Datasheet
ILO Trim
Component Parameters
Drag an ILO Trim component onto your design and double-click it to open the Configure dialog.
General Tab
The General tab is used to set the general operational parameters of the component. It contains
the following parameters. All of these settings are compile-time selections; you do not need to
change these settings at run time.
Implementation
This parameter is used to specify the type of hardware used to implement the ILO Trim
component. It can be either Fixed Function or UDB.
Clocking Information



Reference clock nominal frequency: Displays the reference clock frequency in kHz.
ILO clock nominal frequency: Displays the frequency of the target ILO in kHz
Ratio: Displays the ratio of the reference clock to the ILO clock. This can then be used to
adjust the reference clock to an acceptable value.
Note If this ratio is outside the supported range, then an information bubble will appear to
help the user choose the correct reference clock.
Document Number: 001-86907 Rev. **
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®
ILO Trim
PSoC Creator™ Component Datasheet
Clock Selection
The ILO Trim component contains an embedded ILO clock. This clock can be configured by
modifying the ILO clock value in the design wide resources manager. The component also
requires an external reference clock by attaching a clock source. This clock must be within the
valid range of reference to ILO ratio.
Application Programming Interface
Application Programming Interface (API) routines allow you to configure the component using
software. The following table lists and describes the interface to each function. The subsequent
sections discuss each function in more detail.
By default, PSoC Creator assigns the instance name “ILO_Trim_1” to the first instance of a
component in a given design. You can rename the instance to any unique value that follows the
syntactic rules for identifiers. The instance name becomes the prefix of every global function
name, variable, and constant symbol. For readability, the instance name used in the following
table is “ILO_Trim.”
Function
Description
ILO_Trim_Start()
Initializes and starts the component.
ILO_Trim_Stop()
Stops the component.
ILO_Trim_BeginTrimming()
Begins the implementation of the ILO trimming algorithm.
ILO_Trim_StopTrimming()
Disables the trimming algorithm.
ILO_Trim_CheckStatus()
Returns the current status of the ILO and the trimming algorithm.
ILO_Trim_CheckError()
Calculates ILO frequency error in parts per thousand.
ILO_Trim_Compensate()
Compensates for the ILO clock inaccuracy by converting from a desired
nominal number of clock cycles to the effective number of ILO clock
cycles required based on the current accuracy of the ILO.
ILO_Trim_RestoreTrim()
Restores the factory trim value.
ILO_Trim_GetTrim()
Returns the current ILO trim value.
ILO_Trim_SetTrim()
Returns the called number of words from the given address. If any
address does not belong to the allocated register space, an error is
returned.
ILO_Trim_Sleep()
Stops the component and saves the user configuration
ILO_Trim_Wakeup()
Restores the user configuration and enables the component
ILO_Trim_SaveConfig()
Saves the current user configuration of the component.
ILO_Trim_RestoreConfig()
Restores the current user configuration of the component
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Document Number: 001-86907 Rev. **
®
PSoC Creator™ Component Datasheet
ILO Trim
void ILO_Trim_Start(void)
Description:
Starts the measurement of the ILO accuracy.
Parameters:
None
Return Value:
None
Side Effects:
None
void ILO_Trim_Stop(void)
Description:
Stops the measurement of the ILO accuracy. If trimming is currently active, then the
trimming algorithm is also terminated at this point.
Parameters:
None
Return Value:
None
Side Effects:
None
void ILO_Trim_BeginTrimming(void)
Description:
Begins the implementation of the ILO trimming algorithm. The algorithm requires multiple
ILO clock periods to converge with an accurately trimmed ILO clock frequency. This
function is non-blocking and will return after configuring an interrupt process to implement
the trimming algorithm. ILO_Trim_CheckStatus() and ILO_Trim_CheckError() can be used
to determine the current status of the algorithm. Once the trimming algorithm converges on
an accurately trimmed ILO frequency the background trimming algorithm is disabled.
Not Supported for PSoC 4.
Parameters:
None
Return Value:
None
Side Effects:
None
void ILO_Trim_StopTrimming(void)
Description:
Disables the trimming algorithm that was started by the ILO_Trim_BeginTrimming()
function. This function is only used to terminate the trimming algorithm early. Normal
operation of the trimming algorithm does not use this function since the algorithm will
disable trimming once the ILO accuracy has been achieved.
Not Supported for PSoC 4.
Parameters:
None
Return Value:
None
Side Effects:
None
Document Number: 001-86907 Rev. **
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ILO Trim
PSoC Creator™ Component Datasheet
uint8 ILO_Trim_CheckStatus(void)
Description:
Returns the current status of the ILO and the trimming algorithm. The accuracy status is not
reliable until two ILO clock cycles have occurred since the component was started.
Not Supported for PSoC 4.
Parameters:
None
Return Value:
Set of bit fields that indicate the status of the component. Multiple bit fields can be set at the
same time.
Value
Side Effects:
Description
ILO_Trim_IS_ACCURATE
ILO accuracy is within the required error range.
ILO_Trim_TRIMMING
Trimming algorithm is currently running
None
int16 ILO_Trim_CheckError(void)
Description:
Calculates ILO frequency error in parts per thousand. A positive number indicates that the
ILO is running fast and a negative number indicates that the ILO is running slow. This error
is relative to the error in the reference clock, so the absolute error will be higher and
depend on the accuracy of the reference. The accuracy error is not reliable until two ILO
clock cycles have occurred since the component was started.
Parameters:
None
Return Value:
Error value in parts per thousand.
Side Effects:
None
uint16 ILO_Trim_Compensate(uint16 clocks)
Description:
Compensates for the ILO clock inaccuracy by converting from a desired nominal number of
clock cycles to the effective number of ILO clock cycles required based on the current
accuracy of the ILO. The returned value can then be used instead of the nominal value
when configuring timers that are based on the ILO. If the calculated result exceeds the
capacity of the 16 bit return value, it will be saturated at the maximum 16-bit value.
This function is an alternative to trimming the frequency of the ILO and should not be used
in conjunction with the BeginTrimming() function.
Parameters:
uint16 clocks: Number of nominal ILO clocks desired
Return Value:
uint16: Number of actual ILO clocks required
Side Effects:
None
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Document Number: 001-86907 Rev. **
®
PSoC Creator™ Component Datasheet
ILO Trim
void ILO_Trim_RestoreTrim(void)
Description:
Restore the factory trim value.
Not Supported for PSoC 4.
Parameters:
None
Return Value:
None
Side Effects:
None.
uint8 ILO_Trim_GetTrim(void)
Description:
Returns the current ILO trim value.
Not Supported for PSoC 4.
Parameters:
None
Return Value:
uint8 trim register value
Side Effects:
None
void ILO_Trim_SetTrim(uint8 trim)
Description:
Sets the ILO trim value.
Not Supported for PSoC 4.
Parameters:
uint8 trim: Value to be written into the ILO trim register, where trim[3:0] are the fine trim
values. For PSoC 3 and PSoC 5LP, trim[5:4] are the coarse trim values.
Return Value:
None
Side Effects:
None
void ILO_Trim_Sleep(void)
Description:
Prepares the component for sleep. If the component is currently enabled it will be disabled
and reenabled by ILO_Trim_Wakeup().
Parameters:
None
Return Value:
None
Side Effects:
None
Document Number: 001-86907 Rev. **
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ILO Trim
PSoC Creator™ Component Datasheet
void ILO_Trim_Wakeup(void)
Description:
Returns the component to its state before the call to ILO_Trim_Sleep(). In order to trim the
ILO after waking from a low power mode the ILO_Trim_BeginTrimming() must be called.
Parameters:
None
Return Value:
None
Side Effects:
None
void ILO_Trim_SaveConfig(void)
Description:
Saves the configuration of the component. This routine is called by ILO_Trim_Sleep() to
save the configuration.
Parameters:
None
Return Value:
None
Side Effects:
None
void ILO_Trim_RestoreConfig(void)
Description:
Restores the configuration of the component. This routine is called by ILO_Trim_Wakeup()
to restore the configuration.
Parameters:
None
Return Value:
None
Side Effects:
None
Sample Firmware Source Code
PSoC Creator provides many example projects that include schematics and example code in the
Find Example Project dialog. For component-specific examples, open the dialog from the
Component Catalog or an instance of the component in a schematic. For general examples,
open the dialog from the Start Page or File menu. As needed, use the Filter Options in the
dialog to narrow the list of projects available to select.
Refer to the “Find Example Project” topic in the PSoC Creator Help for more information.
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Document Number: 001-86907 Rev. **
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PSoC Creator™ Component Datasheet
ILO Trim
Functional Description
Implementation
The ILO Trim component uses a down counter to continuously count the number of reference
clock cycles occurring in a single period of the ILO. This information is used to change the ILO
trim value to incrementally approach the target ILO frequency.
Trim Procedure
The operation of the component is as follows.
1) The component is configured to either UDB or Fixed Function and an appropriate
reference clock is provided in the customizer.
2) The reference clock is used as the clock to the counter.
3) At the rising edge of the ILO, the current counter value is captured into the capture
register. This triggers an ISR containing the trimming routine.
4) The trimming routine sequentially and incrementally approaches the target ILO by
changing the ILO trim value by 1 per iteration.
5) Steps 3 and 4 are repeated until the trim value is within 10% of the target ILO or better.
6) The user may call CheckStatus() and CheckError() APIs any time to check the trimming
status and the ILO error respectively.
Compensation Procedure
Alternatively, compensation can be used to find the compensated counter value to meet the
desired timing requirements. For example suppose that the target time desired from a counter td
in the user’s application be denoted as:
td = Co / fILO
where Co is the original counter value, and fILO is frequency of the ILO. Since the ILO may not be
trimmed, the actual time ta can vary by +/- z%.
ta = Co / fILO + z
The compensation procedure then returns the correct counter value Cc to meet the desired
timing requirements to within +/- 10%.
Co = (fILO + z)td
Document Number: 001-86907 Rev. **
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ILO Trim
PSoC Creator™ Component Datasheet
Resources
The ILO Trim component uses either 1 UDB or 1 Fixed-Function Timer block depending on the
mode chosen. It contains 1 embedded ILO clock and 1 interrupt.
Resource Type
Configuration
Datapath
Cells
Macrocells
Status
Cells
Control
Cells
Fixed
Function
Clock
Interrupts
UDB
1
3
1
1
-
1
1
Fixed Function:
-
-
-
-
1 (Timer)
1
1
-
-
-
-
1 (TCPWM)
1
1
PSoC 3, PSoC 5LP
Fixed Function: PSoC4
API Memory Usage
The component memory usage varies significantly, depending on the compiler, device, number
of APIs used and component configuration. The following table provides the memory usage for
all APIs available in the given component configuration.
The measurements have been done with associated compiler configured in Release mode with
optimization set for Size. For a specific design the map file generated by the compiler can be
analyzed to determine the memory usage.
PSoC 3 (Keil_PK51)
Configuration
PSoC 4 (GCC)
PSoC 5LP (GCC)
Flash
SRAM
Flash
SRAM
Flash
SRAM
Bytes
Bytes
Bytes
Bytes
Bytes
Bytes
UDB
1100
9
484
20
1328
12
Fixed Function
1166
7
492
21
1420
12
MISRA Compliance
This section describes the MISRA-C:2004 compliance and deviations for the component. There
are two types of deviations defined:


project deviations – deviations that are applicable for all PSoC Creator components
specific deviations – deviations that are applicable only for this component
This section provides information on component-specific deviations. Project deviations are
described in the MISRA Compliance section of the System Reference Guide along with
information on the MISRA compliance verification environment.
The ILO Trim component does not have any specific deviations.
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Document Number: 001-86907 Rev. **
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PSoC Creator™ Component Datasheet
ILO Trim
This component has the following embedded component - Interrupt. Refer to the corresponding
component datasheet for information on their MISRA compliance and specific deviations.
DC and AC Electrical Characteristics: PSoC 3
Specifications are valid for –40 °C ≤ TA ≤ 85 °C and TJ ≤ 100 °C, except where noted.
Specifications are valid for 1.71 V to 5.5 V, except where noted.
DC Characteristics
Mode
Fixed
Function
UDB
Description
16-bit Fixed Function timer
block current consumption
8-bit UDB timer block current
consumption
Conditions
Min
Typ
Max
Input clock frequency – 3 MHz
–
15
–
μA
Input clock frequency –12 MHz
–
60
–
μA
Input clock frequency – 48 MHz
–
260
–
μA
Input clock frequency – 67 MHz
–
350
–
μA
–
6
–
μA/MHz
–
Units
DC and AC Electrical Characteristics: PSoC 4
Specifications are valid for –40 °C ≤ TA ≤ 85 °C and TJ ≤ 100 °C, except where noted.
Specifications are valid for 1.71 V to 5.5 V, except where noted.
DC Characteristics
Mode
Description
Conditions
Input clock frequency – 3 MHz
Fixed
Function
UDB
16-bit Fixed Function TCPWM
Input clock frequency –12 MHz
block current consumption
Input clock frequency – 48 MHz
8-bit UDB timer block current
consumption
Document Number: 001-86907 Rev. **
–
Min
Typ
Max
Units
–
19
–
μA
–
66
–
μA
–
270
–
μA
–
6
–
μA/MHz
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ILO Trim
PSoC Creator™ Component Datasheet
DC and AC Electrical Characteristics - PSoC 5LP
Specifications are valid for –40 °C ≤ TA ≤ 85 °C and TJ ≤ 100 °C, except where noted.
Specifications are valid for 1.71 V to 5.5 V, except where noted.
DC Characteristics
Mode
Fixed
Function
UDB
Description
16-bit Fixed Function timer
block current consumption
8-bit UDB timer block current
consumption
Conditions
Min
Typ
Max
Input clock frequency – 3 MHz
–
65
–
μA
Input clock frequency –12 MHz
–
170
–
μA
Input clock frequency – 48 MHz
–
650
–
μA
Input clock frequency – 67 MHz
–
900
–
μA
–
6
–
μA/MHz
–
Units
DC and AC Electrical Characteristics: Timing
Specifications are valid for –40 °C ≤ TA ≤ 85 °C and TJ ≤ 100 °C, except where noted.
Specifications are valid for 1.71 V to 5.5 V, except where noted.
PSoC 4
Symbol
Description
Compensated ILO
accuracy
Conditions
ref_clk is ±2% accurate, ratio
of ref_clk to ILO>=50,
count>=20
Min
Typ
-10
Max
10
Units
%
(Preliminary) PSoC 3 and PSoC 5LP: 1 kHz ILO
Symbol
Description
Absolute post-trim ILO
accuracy
Conditions
ref_clk is ±2% accurate, ratio
of ref_clk to ILO>=50
Min
Typ
-10
Worst case trim time
Max
Units
10
%
139.6
ms
(Preliminary) PSoC 3 and PSoC 5LP: 100 kHz ILO
Symbol
Description
Absolute post-trim ILO
accuracy
Worst case trim time
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Conditions
ref_clk is ±2% accurate, ratio
of ref_clk to ILO>=50
Min
-10
Typ
Max
Units
10
%
2.6
ms
Document Number: 001-86907 Rev. **
®
PSoC Creator™ Component Datasheet
ILO Trim
Component Changes
This section lists the major changes in the component from the previous version.
Version
1.0
Description of Changes
Reason for Changes / Impact
First release of this component.
© Cypress Semiconductor Corporation, 2013. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of
any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be used
for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its products for
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specified above is prohibited without the express written permission of Cypress.
Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described herein.
Cypress does not assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in lifesupport systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application
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Use may be limited by and subject to the applicable Cypress software license agreement.
Document Number: 001-86907 Rev. **
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