Component - 8-Bit Voltage DAC (VDAC8) V1.70 Datasheet.pdf

®
PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
1.70
Features
 Voltage output ranges: 1.020-V and 4.080-V full scale
 Software- or clock-driven output strobe
 Data source can be CPU, DMA, or UDB
General Description
The VDAC8 component is an 8-bit voltage output Digital to Analog Converter (DAC). The output
range can be from 0 to 1.020 V (4 mV/bit) or from 0 to 4.08 V (16 mV/bit). The VDAC8 can be
controlled by hardware, software, or a combination of both hardware and software.
Input/Output Connections
This section describes the various input and output connections for the VDAC8. An asterisk (*) in
the list of I/Os indicates that the I/O may be hidden on the symbol under the conditions listed in
the description of that I/O.
Vout – Analog
The Vout terminal is the connection to the DAC’s voltage output. It may be routed to any analogcompatible pin on the PSoC.
Note The VDAC, when driven to a pin, cannot drive a value that exceeds the VDDIO for that pin.
To get the result you want, set the correct VDDIO supply.
data[7:0] – Input *
This 8-bit-wide data signal connects the VDAC8 directly to the DAC Bus. The DAC Bus may be
driven by UDB-based components or control registers, or it may be routed directly from GPIO
pins. This input is enabled by setting the Data_Source parameter to DAC Bus. If the CPU or
DMA option is selected instead, the bus connection will disappear from the component symbol.
Use the data[7:0] input when hardware is capable of setting the proper value without CPU
intervention. When using this option, the strobe option should be set as External as well.
Cypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600
Document Number: 001-69975 Rev. *A
Revised November 9, 2011
8-Bit Voltage Digital to Analog Converter (VDAC8)
®
PSoC Creator™ Component Datasheet
For many applications this input is not required, but instead the CPU or DMA will write a value
directly to the data register. In firmware, use the VDAC8_SetValue() function or directly write a
value to the VDAC8 data register.
strobe – Input *
The strobe input is an optional signal input and is selected with the StrobeMode parameter.

If StrobeMode is set to External, the strobe pin is visible and must be connected to a valid
digital source. In this mode the data is transferred from the VDAC8 register to the DAC on the
next positive edge of the strobe signal.

If StrobeMode is set to Register Write, the pin disappears from the symbol and any write to
the data registers is immediately transferred to the DAC.
For audio or periodic sampling applications, the same clock used to clock the data into the DAC
can also be used to generate an interrupt. In this case, each rising edge of the clock would
transfer data to the DAC and cause an interrupt to get the next value loaded into the DAC
register.
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Document Number: 001-69975 Rev. *A
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Component Parameters
Drag a VDAC8 component onto your design and double click it to open the Configure dialog.
The VDAC8 component provides the following parameters.
Range
This parameter allows you to set one of two voltage ranges as the default value. The range may
be changed at any time during runtime with the VDAC8_SetRange() function.
Range
Lowest Value
Highest Value
Step Size
Range_1_Volt
0.0 mV
1.020 V
4 mV
Range_4_Volt
0.0 mV
4.080 V
16 mV
Output equations:


1-V range: VOUT = (value/256) × 1.024 V
4-V range: VOUT = (value/256) × 4.096 V
Note The term “value” is a number between 0 and 255.
Document Number: 001-69975 Rev. *A
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8-Bit Voltage Digital to Analog Converter (VDAC8)
®
PSoC Creator™ Component Datasheet
Value
This is the initial value the VDAC8 presents after the VDAC8_Start() command is executed. The
VDAC8_SetValue() function or a direct write to the DAC register will override the default value at
anytime. Legal values are between 0 and FF, inclusive. The mV field represents VDAC output
voltage in millivolts and the 8 bit Hex field represents VDAC input data value in Hex.
Speed
This parameter provides two settings: Slow and Fast. In Slow mode, the settling time is slower
but consumes less operating current. In Fast mode, the voltage settles much faster, but at a cost
of more operating current.
Data Source
This parameter selects the source of the data to be written into the DAC register. If you want the
CPU (firmware) or the DMA to write data to the VDAC8, select CPU or DMA (Data Bus). If you
want data to be written directly from the UDBs or a UDB-based component, select DAC Bus.
When DAC Bus is selected, the input is indicated on the VDAC symbol. There is only one DAC
Bus, so multiple VDACs cannot have independent hardware (UDB) data sources.
When Data Source is set as DAC Bus, the customizer automatically sets the Strobe Mode to
External and disables the option so that you cannot change it.
Note For PSoC 5 silicon, a write of a new value to the DAC may result in an indeterminate value
on the DAC output. To output the desired value, write or strobe the DAC twice with the same
value. Because the first write may result in an indeterminate output, the time between the two
writes should be minimized. This applies to writes by CPU, DMA, and strobe. The API
IDAC8_SetValue() writes the value provided twice to mitigate this issue for CPU writes.
Strobe Mode
This parameter selects whether the data is immediately written to the DAC when the data is
written into the VDAC8 data register. This mode is enabled when the Register Write option is
selected. When the External option is selected, a clock or signal from the UDBs controls when
the data is written from the DAC register to the actual DAC.
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Document Number: 001-69975 Rev. *A
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Resources
The VDAC8 component uses one viDAC8 analog block.
API Memory
(Bytes)
Digital Blocks
Analog Blocks
Datapaths
Macro
cells
Status
Registers
Control
Registers
Counter7
Flash
RAM
Pins (per
External I/O)
N/A
N/A
N/A
N/A
N/A
354
3
1
1 viDAC8 HW
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 cover each function in more detail.
By default, PSoC Creator assigns the instance name “VDAC8_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 “VDAC8.”
Function
Description
VDAC8_Start()
Initializes the VDAC8 with default customizer values.
VDAC8_Stop()
Disables the VDAC8 and sets it to the lowest power state.
VDAC8_SetSpeed()
Sets DAC speed.
VDAC8_SetValue()
Sets value between 0 and 255 with the given range.
VDAC8_SetRange()
Sets range to 1 or 4 volts.
VDAC8_Sleep()
Stops and saves the user configuration.
VDAC8_WakeUp()
Restores and enables the user configuration.
VDAC8_Init()
Initializes or restores default VDAC8 configuration
VDAC8_Enable()
Enables the VDAC8.
VDAC8_SaveConfig()
Saves nonretention DAC data register value.
VDAC8_RestoreConfig()
Restores nonretention DAC data register value
Document Number: 001-69975 Rev. *A
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8-Bit Voltage Digital to Analog Converter (VDAC8)
PSoC Creator™ Component Datasheet
Global Variables
Variable
VDAC8_initVar
Description
Indicates whether the VDAC8 has been initialized. The variable is initialized to 0 and set to 1 the
first time VDAC8_Start() is called. This allows the component to restart without reinitialization
after the first call to the VDAC8_Start() routine.
If reinitialization of the component is required, then the VDAC8_Init() function can be called
before the VDAC8_Start() or VDAC8_Enable() function.
void VDAC8_Start(void)
Description:
This is the preferred method to begin component operation. VDAC8_Start() sets the initVar
variable, calls the VDAC8_Init() function, calls the VDAC8_Enable() function, and powers up
the VDAC8 to the given power level. A power level of 0 is the same as executing the
VDAC_Stop() function.
Parameters:
None
Return Value:
None
Side Effects:
If the initVar variable is already set, this function only calls the VDAC8_Enable() function.
void VDAC8_Stop(void)
Description:
Powers down VDAC8 to lowest power state and disables output.
Note This API is not recommended for use on PSoC 3 ES2 and PSoC 5 silicon. These
devices have a defect that causes connections to several analog resources to be
unreliable when not powered. The unreliability manifests itself in silent failures (for
example, unpredictably bad results from analog components) when the component using
that resource is stopped. VDAC8 components should always be powered up (by calling
the VDAC8_Start() API). Do not call the VDAC8_Stop() API.
Parameters:
None
Return Value:
None
Side Effects:
None
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
void VDAC8_SetSpeed(uint8 speed)
Description:
Set DAC speed.
Parameters:
uint8 speed: Sets DAC speed. See the following table for valid parameters.
Option
Description
VDAC8_LOWSPEED
Low speed (low power)
VDAC8_HIGHSPEED
High speed (high power)
Return Value:
None
Side Effects:
None
void VDAC8_SetRange(uint8 range)
Description:
Sets range to 1 or 4 volts.
Parameters:
uint8 range: Sets full-scale range for VDAC8. See the following table for ranges.
Option
Description
VDAC8_RANGE_1V
Sets full-scale range of 1.020 V
VDAC8_RANGE_4V
Set full-scale range of 4.080 V
Return Value:
None
Side Effects:
None
void VDAC8_SetValue(uint8 value)
Description:
Sets value to output on VDAC8. Valid values are between 0 and 255.
Parameters:
uint8 value: Value between 0 and 255. A value of 0 is the lowest (zero) and a value of 255 is
the full-scale value. The full-scale value is dependent on the range, which is selected with the
VDAC8_SetRange() API.
Return Value:
None
Side Effects:
On PSoC 3 ES2, PSoC 3 Production, and PSoC 5 silicon, the VDAC8_SetValue() function
should be called after enabling power to the VDAC.
Document Number: 001-69975 Rev. *A
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8-Bit Voltage Digital to Analog Converter (VDAC8)
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PSoC Creator™ Component Datasheet
void VDAC8_Sleep(void)
Description:
This is the preferred API to prepare the component for sleep. The VDAC8_Sleep() API saves
the current component state. Then it calls the VDAC8_Stop() function and calls
VDAC8_SaveConfig() to save the hardware configuration.
Call the VDAC8_Sleep() function before calling the CyPmSleep() or the CyPmHibernate()
function. Refer to the PSoC Creator System Reference Guide for more information about
power management functions.
Parameters:
None
Return Value:
None
Side Effects:
None
void VDAC8_Wakeup(void)
Description:
This is the preferred API to restore the component to the state when VDAC8_Sleep() was
called. The VDAC8_Wakeup() function calls the VDAC8_RestoreConfig() function to restore
the configuration. If the component was enabled before the VDAC8_Sleep() function was
called, the VDAC8_Wakeup() function will also re-enable the component.
Parameters:
None
Return Value:
None
Side Effects:
Calling the VDAC8_Wakeup() function without first calling the VDAC8_Sleep() or
VDAC8_SaveConfig() function may produce unexpected behavior.
void VDAC8_Init(void)
Description:
Initializes or restores the component according to the customizer Configure dialog settings. It
is not necessary to call VDAC8_Init() because the VDAC8_Start() API calls this function and
is the preferred method to begin component operation.
Parameters:
None
Return Value:
None
Side Effects:
All registers will be set to their initial values. This will reinitialize the component. Calling the
VDAC8_Init() function requires a call to VDAC8_SetValue() if you intend to set a new value
other than what is currently in the register.
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
void VDAC8_Enable(void)
Description:
Activates the hardware and begins component operation. It is not necessary to call
VDAC8_Enable() because the VDAC8_Start() API calls this function, which is the preferred
method to begin component operation.
Parameters:
None
Return Value:
None
Side Effects:
None
void VDAC8_SaveConfig(void)
Description:
This function saves the component configuration and nonretention registers. This function
will also save the current component parameter values, as defined in the Configure dialog or
as modified by appropriate APIs. This function is called by the VDAC8_Sleep() function.
Parameters:
None
Return Value:
None
Side Effects:
None
void VDAC8_RestoreConfig(void)
Description:
This function restores the component configuration and nonretention registers. This function
will also restore the component parameter values to what they were before calling the
VDAC8_Sleep() function.
Parameters:
None
Return Value:
None
Side Effects:
Calling this function before calling VDAC_Sleep() may result in unexpected behavior.
DMA Wizard
VDAC8 components do not require implementation of a DMA Request signal. The typical usage
is signal generation. The data rate to VDAC8 components should be controlled externally. You
can use the DMA Wizard to configure DMA operation as follows:
Name of DMA
Source/Destination in
DMA Wizard
VDAC8_Data_PTR
Direction
DMA Req
Signal
Destination N/A
Document Number: 001-69975 Rev. *A
DMA Req
Type
N/A
Description
Stores the DAC value between 0 and 255
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8-Bit Voltage Digital to Analog Converter (VDAC8)
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PSoC Creator™ Component Datasheet
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.
Functional Description
When used as a VDAC8, the viDAC8 analog block is configured as voltage DAC and can be
used as voltage source.
When used as a VDAC, the output is an 8-bit digital-to-analog conversion voltage to support
applications that need reference voltages. In this case, the reference source is a voltage
reference from the Analog reference block called VREF(DAC). You can configure the DAC to
work in voltage mode by setting the DACx_CR0 [4] register. In this mode, there are two output
ranges selected by the DACx_CR0[3:2] register:


0 V to 1.024 V
0 V to 4.096 V
Both output ranges have 255 equal steps. The VDAC is implemented by driving the output of the
current DAC through resistors and obtaining a voltage output. Because no buffer is used, any
DC current drawn from the DAC affects the output level. Therefore, in this mode any load
connected to the output should be capacitive.
The VDAC can convert up to 1 Msps. Also, the DAC is slower in 4-V mode than 1-V mode,
because the resistive load to VSSA is four times larger. In 4-V mode, the VDAC can convert up to
250 ksps.
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Document Number: 001-69975 Rev. *A
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Block Diagram and Configuration
Figure 1 shows the block diagram for the VDAC8 component.
Figure 1. VDAC8 Block Diagram
VDDA
VCC(Regulated)
DAC Value Mirror
1x, 2x ... 255x (8 bit)
Calibration Mirror
1.024V
Output
ISOURCE
VOUT
R
Reference
Current Source
Scaler
R
3R
Registers
The functions provided with the component support most of the common runtime functions that
most applications require. The following register references provide brief descriptions for the
advanced user. The VDAC8_Data register may be used to write data directly to the DAC without
using an API. This can be useful for either the CPU or DMA.
VDAC8_CR0
Bits
7
6
Value



5
RSVD
4
3
mode
2
Range[1:0]
1
0
hs
RSVD
mode: Sets DAC to either voltage or current mode
Range[1:0]: DAC range settings
hs: Sets data speed
VDAC8_CR1
Bits
Value

7
6
RSVD
5
4
3
2
1
0
mx_data
reset_udb_e
n
mx_idir
idirbit
Mx_ioff
ioffbit
mx_data: Selects data source
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8-Bit Voltage Digital to Analog Converter (VDAC8)





PSoC Creator™ Component Datasheet
reset_udb_en: DAC reset enable
mx_idir: Mux selection for DAC current direction control
idirbit: Register source for DAC current direction
mx_off: Mux selection for DAC current off control
ioffbit: Register source for DAC current off
VDAC8_DATA
Bits
7
6
5
4
Value

3
2
1
0
Data[7:0]
Data[7:0]: DAC data register
DC and AC Electrical Characteristics for PSoC 3
The following values are based on characterization data. Specifications are valid for
–40°C £ TA £ 85 °C and TJ £ 100 °C except where noted. Unless otherwise specified in the
tables below, all Typical values are for T A = 25 °C, VDDA = 5.0 V, output referenced to analog
ground (VSSA), fast mode.
VDAC8 DC Electrical Characteristics
Parameter
Description
Conditions
Resolution
Typ
Max
Units
–
8
–
bits
INL1
Integral nonlinearity
1-V scale
–
±2.1
±2.5
LSB
DNL1
Differential nonlinearity
1-V scale
–
±0.3
±1
LSB
ROUT
Output resistance
1-V scale
–
4
–
k
4-V scale
–
16
–
k
1-V scale
–
1
–
V
4-V scale, VDDA = 5 V
–
4
1
–
V
Monotonicity
–
–
Yes
–
VOS
Zero-scale error
–
0
±0.9
LSB
FSGainErr
Full-scale gain error
1-V scale
–
±1.6
±2.5
%
4-V scale
–
±1.5
±2.5
%
VOUT
1
Min
Output voltage range,
code = 255
For VDDA voltage below 5 V, the output only complies to specifications for output voltages below (V DDA – 1 V).
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Document Number: 001-69975 Rev. *A
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PSoC Creator™ Component Datasheet
Parameter
8-Bit Voltage Digital to Analog Converter (VDAC8)
Description
TCGainErr
IDD
Conditions
Min
Typ
Max
Units
Temperature coefficient,
gain error
1-V scale
–
–
0.02
%FSR/°C
4-V scale
–
–
0.02
%FSR/°C
Operating current
Slow mode
–
–
100
µA
Fast mode
–
–
500
µA
Figures
INL versus DAC Code, 1.0-V Range
INL versus DAC Code, 4.0-V Range
0.8
0.8
0.6
0.6
0.4
0.4
0.2
0.2
Bits
1
Bits
1
0
0
-0.2
-0.2
-0.4
-0.4
-0.6
-0.6
-0.8
1V INL
-1
0
32
64
96
128
160
Code
192
224
-0.8
0
0.2
0.2
0.15
0.15
0.1
0.1
0.05
0.05
Bits
0
-0.05
-0.1
-0.1
1V DNL
-0.2
0
32
64
96
128
160
Code
Document Number: 001-69975 Rev. *A
192
64
96
128
160
Code
192
224
256
0
-0.05
-0.15
32
DNL versus DAC Code, 4.0-V Range
Bits
Typical DNL versus DAC Code, 1.0-V Range
4V INL
-1
256
224
256
-0.15
4V DNL
-0.2
0
32
64
96
128
160
Code
192
224
256
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8-Bit Voltage Digital to Analog Converter (VDAC8)
PSoC Creator™ Component Datasheet
VDAC INL versus Temperature, 1-V Mode
VDAC DNL versus Temperature, 1-V Mode
3.0
1.0
0.9
2.5
0.8
0.7
DNL, LSB
INL, LSB
2.0
1.5
1.0
0.6
0.5
0.4
0.3
0.2
0.5
0.1
0.0
0.0
-40
-20
0
20
40
60
80
-40
-20
0
Temperature, °C
40
60
80
VDAC Full Scale Error versus Temperature, 4-V Mode
1.0
1.0
0.8
0.8
0.6
0.6
Full Scale Error, %
Full Scale Error, %
VDAC Full Scale Error versus Temperature, 1-V Mode
0.4
0.2
0.0
-0.2
-0.4
0.4
0.2
0.0
-0.2
-0.4
-0.6
-0.6
-0.8
-0.8
-1.0
-1.0
-40
-20
0
20
40
60
80
-40
-20
0
20
Temperature, °C
400
90
350
Operating Current. µA
80
70
60
Max, Vdda = 5.5 V
40
Max, Vdda = 2.7 V
30
60
80
VDAC Operating Current versus Temperature, 1-V
Mode, Fast Mode
100
50
40
Temperature, °C
VDAC Operating Current versus Temperature, 1-V
Mode, Slow Mode
Operating Current. µA
20
Temperature, °C
20
Max, Vdda = 5.5 V
300
250
200
150
100
50
10
0
0
-40
-20
0
20
40
Temperature, °C
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60
80
-40
-20
0
20
40
60
80
Temperature, °C
Document Number: 001-69975 Rev. *A
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PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
VDAC8 AC Electrical Characteristics
Parameter
FDAC
Description
Conditions
Min
Typ
Max
1-V scale
–
–
1000
ksps
4-V scale
–
–
250
ksps
Settling time to 0.1%,
step 25% to 75%
1-V scale, CLOAD = 15 pF
–
0.45
1
µs
4-V scale, CLOAD = 15 pF
–
0.8
3.2
µs
Settling time to 0.1%,
step 75% to 25%
1-V scale, CLOAD = 15 pF
–
0.45
1
µs
4-V scale, CLOAD = 15 pF
–
0.7
3
µs
Slew rate, step 10% to 90%
1-V scale, CLOAD = 15 pF
–
0.3
0.5
µs
4-V scale, CLOAD = 15 pF
–
0.5
1.3
µs
1-V scale, CLOAD = 15 pF
–
0.3
0.5
µs
4-V scale, CLOAD = 15 pF
–
0.3
1.3
µs
2
4-V scale, code 255
–
3
–
µV/rtHz
2
1-V scale, code 255
–
750
–
nV/rtHz
Update rate
TsettleP
TsettleN
SRP
SRN
Slew rate, step 90% to 10%
Vn4V
Noise density
Vn1V
Noise density
Units
Figures
Noise Levels, Scale 4 V
Noise Levels, Scale 1 V
100000
Scale = 4 V, Code = 255
Scale = 4 V, Code = 64
100000
10000
10000
nV/rtHz
nV/rtHz
1000
1000
100
100
Voltage Noise proportional to Scale * Code
Voltage Noise proportional to Scale * Code
10
0.01
2
Scale = 1 V, Code = 255
Scale = 1 V, Code = 64
0.1
1
kHz 10
100
1000
10
0.01
0.1
1
kHz 10
100
1000
Output noise is directly proportional to code value.
Document Number: 001-69975 Rev. *A
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8-Bit Voltage Digital to Analog Converter (VDAC8)
PSoC Creator™ Component Datasheet
DC and AC Electrical Characteristics for PSoC 5
The following values are based on characterization data. Specifications are valid for
–40°C £ TA £ 85 °C and TJ £ 100 °C, except where noted. Unless otherwise specified in the
following tables, all Typical values are for T A = 25 °C, VDDA = 5.0 V, output referenced to analog
ground (VSSA), fast mode.
VDAC8 DC Electrical Characteristics
Parameter
Description
Conditions
Resolution
Typ
Max
Units
–
8
–
bits
INL1
Integral nonlinearity
1-V scale
–
±2.1
±2.5
LSB
DNL1
Differential nonlinearity
1-V scale
–
±0.3
±1
LSB
ROUT
Output resistance
1-V scale
–
4
–
k
4-V scale
–
16
–
k
1-V scale
–
1.02
–
V
4-V scale, VDDA = 5 V
–
4.08
–
V
Monotonicity
–
–
Yes
–
VOS
Zero-scale error
–
0
±0.9
LSB
Eg
Gain error
1-V scale
–
–
±5
%
4-V scale
–
–
±5
%
Temperature coefficient,
gain error
1-V scale
–
–
0.03
%FSR/°C
4-V scale
–
–
0.03
%FSR/°C
Operating current
4-V Slow mode
–
–
100
µA
4-V Fast mode
–
–
500
µA
1-V Slow mode
300
µA
1-V Fast mode
600
µA
VOUT
TC_Eg
IDD
3
Min
Output voltage range,
code = 255
3
For VDDA voltage below 5 V, the output only complies to specifications for output voltages below (V DDA – 1 V).
Page 16 of 21
Document Number: 001-69975 Rev. *A
®
PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Figures
VDAC DNL versus Input Code, 1-V Mode
1
1
0.5
0.5
DNL, LSB
INL, LSB
VDAC INL versus Input Code, 1-V Mode
0
-0.5
0
-0.5
-1
0
32
64
96
128
160
192
224
-1
256
0
32
64
96
Code, 8-bit
128
160
192
224
256
Code, 8-bit
VDAC INL versus Temperature, 1-V Mode
VDAC DNL versus Temperature, 1-V Mode
1
0.2
DNL, LSB
INL, LSB
0.5
0
0.1
-0.5
-1
-40
-20
0
20
40
Temperature, °C
60
80
-40
VDAC Full Scale Error versus Temperature, 1-V Mode
2
2
1.5
1.5
1
1
0.5
0
-0.5
-1
-1.5
-20
0
20
40
Temperature, °C
60
80
VDAC Full Scale Error versus Temperature, 4-V Mode
Full Scale Error, %
Full Scale Error, %
0
0.5
0
-0.5
-1
-1.5
-2
-40
-20
0
20
40
Temperature, °C
Document Number: 001-69975 Rev. *A
60
80
-2
-40
-20
0
20
40
Temperature, °C
60
80
Page 17 of 21
®
8-Bit Voltage Digital to Analog Converter (VDAC8)
PSoC Creator™ Component Datasheet
VDAC Operating Current versus Temperature, 1-V
Mode, Fast Mode
500
500
400
400
Operating Current, µA
Operating Current, µA
VDAC Operating Current versus Temperature, 1-V
Mode, Slow Mode
300
200
100
0
300
200
100
0
-40
-20
0
20
40
Temperature, °C
60
80
-40
-20
0
20
40
Temperature, °C
60
80
VDAC8 AC Electrical Characteristics
Parameter
FDAC
TsettleP
TsettleN
Page 18 of 21
Description
Min
Typ
Max
1-V scale
–
–
1000
ksps
4-V scale
–
–
250
ksps
Settling time to 0.1%,
step 25% to 75%
1-V scale, CLOAD = 15 pF
–
0.45
1
µs
4-V scale, CLOAD = 15 pF
–
0.8
4
µs
Settling time to 0.1%,
step 75% to 25%
1-V scale, CLOAD = 15 pF
–
0.45
1
µs
4-V scale, CLOAD = 15 pF
–
0.7
4
µs
Voltage Noise
Range = 1 V, fast mode,
VDDA = 5 V, 10 kHz
–
750
–
nVsqrtHz
Update rate
Conditions
Units
Document Number: 001-69975 Rev. *A
®
PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Figures
VDAC Step Response, Codes 0x40 to 0xC0, 1-V
Mode, Fast Mode, VDDA = 5 V
VDAC Glitch Response, Codes 0x7F to 0x80, 1-V
Mode, Fast Mode, VDDA = 5 V
0.9
0.56
0.8
0.7
0.54
0.5
Vout, V
Vout, V
0.6
0.4
0.52
0.3
0.50
0.2
0.1
0.0
0.48
0
1
2
3
4
5
Time, µs
0
1
2
3
4
5
Time, µs
VDAC PSRR versus Frequency
40
PSRR, dB
30
20
4 V, code 0x7F
10
4 V, code 0xFF
0
0.1
1
10
100
1000
Frequency, kHz
Terminology
Integral Nonlinearity (INL)
INL, integral nonlinearity, is a measure of the maximum deviation, in LSBs, from a best fit
straight line over the operating range of the DAC.
Differential Nonlinearity (DNL)
DNL, differential nonlinearity, is the difference between the measured change and the ideal
1-LSB change between any two adjacent codes. This VDAC is guaranteed monotonic by design.
The output is “thermometer-encoded;” each successive step is made by turning on a separate
output source which is summed with previously enabled output sources.
Document Number: 001-69975 Rev. *A
Page 19 of 21
8-Bit Voltage Digital to Analog Converter (VDAC8)
®
PSoC Creator™ Component Datasheet
Montonicity
A DAC is defined as monotonic if the output increases or stays the same with each increasing
digital code input value. The VDAC8 component is monotonic over the full operating range of
voltage and temperature.
Zero-Scale Error
Zero-scale error is the difference between the measured value at code 0x00 and the value of the
best-fit straight line at code 0x00.
Full-Scale Gain Error
Full-scale gain error is the difference between the measured value and the nominal value at
maximum code. The maximum value is either 1.020 V or 4.080 V at code = 255 (0x00).
Full-Scale Gain Temperature Coefficient (TC)
Full-scale gain temperature coefficient is the change in full-scale value (maximum code 0xFF)
with change in temperature. Gain changes at lower values are proportional to code value.
Power Supply Rejection Ratio (PSRR)
Power supply rejection ratio measures the isolation of the VDAC's output from the power supply.
Settling Time
Settling time is the amount of time required for the output to settle to a specific level for a specific
digital input change.
Slew Rate
The slew rate is the maximum rate of change of the output of the VDAC. Slew rate is measured
from 10 percent to 90 percent of full-scale value
Glitch Amplitude
Glitch amplitude is the peak amplitude of the pulse injected into the output when the input code
changes a single count at mid-scale (0x7F to 0x80). The pulse is greater than the difference
between the static values before and after data change.
Voltage Noise
Voltage noise is the sum of the noise of the VDAC's output resistance and the current output
noise times the output resistance of the VDAC. This noise varies as a function of code value.
Page 20 of 21
Document Number: 001-69975 Rev. *A
®
PSoC Creator™ Component Datasheet
8-Bit Voltage Digital to Analog Converter (VDAC8)
Component Changes
This section lists the major changes in the component from the previous version.
Version
1.70.a
Description of Changes
Reason for Changes / Impact
Added DC and AC Electrical
characteristics data for PSoC 5
Minor datasheet edits and updates
1.70
1.60
VDAC8_Stop() API modified for
PSoC 5
Change required to prevent the component from impacting
unrelated analog signals when stopped, when using PSoC 5.
Updated VDAC customizer.

To make VDAC layout same as IDAC layout.

To force the Strobe mode to External when Data Source is
selected as DAC Bus.
Added a GUI Configuration Editor
Previous configuration window did not provide enough
information for ease of use.
Added characterization data to
datasheet
Minor datasheet edits and updates
1.50
Added Sleep/Wakeup and
Init/Enable APIs.
To support low-power modes, and to provide common interfaces
to separate control of initialization and enabling of most
components.
Added DMA capabilities file to the
component.
This file allows the VDAC8 to be supported by the DMA Wizard
tool in PSoC Creator.
© Cypress Semiconductor Corporation, 2011. 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
use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress products in lifesupport systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
PSoC® is a registered trademark, and PSoC Creator™ and Programmable System-on-Chip™ are trademarks of Cypress Semiconductor Corp. All other trademarks or registered trademarks
referenced herein are property of the respective corporations.
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foreign), United States copyright laws and international treaty provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify, create
derivative works of, and compile the Cypress Source Code and derivative works for the sole purpose of creating custom software and or firmware in support of licensee product to be used only in
conjunction with a Cypress integrated circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of this Source Code except as
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
implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Use may be limited by and subject to the applicable Cypress software license agreement.
Document Number: 001-69975 Rev. *A
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