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DAC8550
SLAS476H – MARCH 2006 – REVISED JUNE 2017
DAC8550 16-bit, Ultra-Low Glitch, Voltage Output Digital-To-Analog Converter
1 Features
3 Description
•
•
•
•
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The DAC8550 is a small, low-power, voltage output,
16-bit digital-to-analog converter (DAC). It is
monotonic, provides good linearity, and minimizes
undesired code-to-code transient voltages. The
DAC8550 uses a versatile, 3-wire serial interface that
operates at clock rates of up to 30 MHz and is
compatible
with
standard
SPI™,
QSPI™,
Microwire™, and digital signal processor (DSP)
interfaces.
1
•
•
•
•
•
•
Relative Accuracy: 8 LSB
Glitch Energy: 0.1 nV-s
MicroPower Operation: 140 μA at 2.7 V
Power-On Reset to Midscale
Power Supply: 2.7 V to 5.5 V
16-Bit Monotonic
Settling Time: 10 μs to ±0.003% FSR
Low-Power Serial Interface with Schmitt-Triggered
Inputs
On-Chip Output Buffer Amplifier with Rail-to-Rail
Output Amplifier
Power-Down Capability
2's Complement Input
SYNC Interrupt Facility
Drop-In Compatible with DAC8531/01 and
DAC8551 (Binary Input)
Available in a Tiny MSOP-8 Package
The DAC8550 requires an external reference voltage
to set its output range. The DAC8550 incorporates a
power-on reset circuit that ensures that the DAC
output powers up at midscale and remains there until
a valid write takes place to the device. The DAC8550
contains a power-down feature, accessed over the
serial interface, that reduces the current consumption
of the device to 200 nA at 5 V.
The low-power consumption of this device in normal
operation makes it ideal for portable, battery-operated
equipment. Power consumption is 0.38 mW at 2.7 V,
reducing to less than 1 μW in power-down mode.
2 Applications
The DAC8550 is available in an MSOP-8 package.
•
•
•
•
•
•
For additional flexibilty, see the DAC8551, a binarycoded counterpart to the DAC8550.
Process Control
Data Acquisition Systems
Closed-Loop Servo-Control
PC Peripherals
Portable Instrumentation
Programmable Attenuation
Device Information(1)
PART NUMBER
DAC8550
PACKAGE
VSSOP (8)
BODY SIZE (NOM)
3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Functional Block Diagram
VDD
VFB
VREF
REF (+)
16-Bit DAC
VOUT
16
DAC Register
16
SYNC
SCLK
Shift Register
PWB
Control
Resistor
Network
DIN
GND
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
DAC8550
SLAS476H – MARCH 2006 – REVISED JUNE 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
4
5
6.1
6.2
6.3
6.4
6.5
6.6
6.7
5
5
5
5
6
7
8
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Timing Characteristics...............................................
Typical Characteristics ..............................................
Detailed Description ............................................ 16
7.1
7.2
7.3
7.4
Overview .................................................................
Functional Block Diagram .......................................
Feature Description.................................................
Device Functional Modes........................................
16
16
16
18
7.5 Programming........................................................... 18
8
Application and Implementation ........................ 20
8.1 Application Information............................................ 20
8.2 Typical Applications ................................................ 21
8.3 System Examples ................................................... 23
9 Power Supply Recommendations...................... 24
10 Layout................................................................... 24
10.1 Layout Guidelines ................................................. 24
10.2 Layout Example .................................................... 24
11 Device and Documentation Support ................. 25
11.1
11.2
11.3
11.4
11.5
11.6
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
25
25
25
25
25
25
12 Mechanical, Packaging, and Orderable
Information ........................................................... 25
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision G (February 2017) to Revision H
Page
•
Changed the VIL Test Conditions From: VDD = 5 V To: 3 V ≤ VDD ≤ 5.5 V and From: VDD = 3 V To: 2.7 V ≤ VDD < 3 V
in the Electrical Characteristics .............................................................................................................................................. 6
•
Changed the VIH Test Conditions From: VDD = 5 V To: 3 V ≤ VDD ≤ 5.5 V and From: VDD = 3 V To: 2.7 V ≤ VDD < 3 V
in the Electrical Characteristics .............................................................................................................................................. 6
Changes from Revision F (March 2016) to Revision G
Page
•
Relative accuracy DAC8550, Deleted the TYP value of ± 3, Changed the MAX value From: ±8 To: ±16 in the
Electrical Characteristics ....................................................................................................................................................... 6
•
Relative accuracy DAC8550B, Deleted the TYP value of ± 3, Changed the MAX value From: ±8 To: ±12 in the
Electrical Characteristics ....................................................................................................................................................... 6
Changes from Revision E (March 2012) to Revision F
Page
•
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section .................................................................................................. 1
•
Changed Differential nonlinearity Test Conditions From: 16-bit monotonic To: three separate entries in the Electrical
Characteristics ....................................................................................................................................................................... 6
Changes from Revision D (October 2006) to Revision E
Page
•
Changed low-level input voltage values in Electrcial Characteristics..................................................................................... 6
•
Changed high-level input voltage values in Electrcial Characteristics ................................................................................... 6
2
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SLAS476H – MARCH 2006 – REVISED JUNE 2017
Changes from Revision C (March 2006) to Revision D
Page
•
Changed Features .................................................................................................................................................................. 1
•
Changed relative accuracy feature from 8 LSB (Max) to 3 LSB ............................................................................................ 1
•
Changed micropower operation feature from 200 μA at 5 V to 140 μA at 2.7 V.................................................................... 1
•
Changed power consumption from 1 mW at 5 V to 0.38 mW at 2.7 V .................................................................................. 1
•
Changed power-down consumption from 1 mW to less than 1 mW in Description ............................................................... 1
•
Changed relative accuracy for DAC8550 typical value from ±5 to ±3.................................................................................... 6
•
Changed reference current input range for VREF = 5 V from 50 to 40.................................................................................... 6
•
Deleted reference current included from IDD (normal mode) test conditions .......................................................................... 6
•
Changed IDD (normal mode) typical values from 200 and 180 to 160 and 140...................................................................... 6
•
Changed Timing Diagram and Timing Characteristics ........................................................................................................... 7
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DAC8550
SLAS476H – MARCH 2006 – REVISED JUNE 2017
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5 Pin Configuration and Functions
DGK Package
8-Pin VSSOP
Top View
VDD
1
VREF
2
8
GND
7
DIN
DAC8550
VFB
3
6
SCLK
VOUT
4
5
SYNC
Pin Functions
PIN
NAME
NO.
TYPE
DESCRIPTION
VDD
1
PWR
VREF
2
I
Power-supply input
Reference voltage input
VFB
3
I
Feedback connection for the output amplifier
VOUT
4
O
Analog output voltage from DAC. The output amplifier has rail-to-rail operation.
SYNC
5
I
Level-triggered control input (active LOW). This is the frame synchronization signal for the input data.
When SYNC goes LOW, it enables the input shift register and data is transferred in on the falling edges
of the following clocks. The DAC is updated following the 24th clock (unless SYNC is taken HIGH before
this edge, in which case the rising edge of SYNC acts as an interrupt and the write sequence is ignored
by the DAC8550). Schmitt-Trigger logic input.
SCLK
6
I
Serial clock input. Data can be transferred at rates up to 30 MHz Schmitt-Trigger logic input.
DIN
7
I
Serial data input. Data is clocked into the 24-bit input shift register on each falling edge of the serial clock
input. Schmitt-Trigger logic input.
GND
8
GND
4
Ground reference point for all circuitry on the part
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SLAS476H – MARCH 2006 – REVISED JUNE 2017
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN
MAX
Supply voltage
GND
–0.3
6
V
Digital input voltage range
GND
–0.3
VDD + 0.3
V
Output voltage
GND
–0.3
VDD + 0.3
V
150
°C
Junction temperature, TJ(max)
UNIT
Operating temperature, TA
–40
105
°C
Storage temperature, Tstg
–65
150
°C
(1)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
±2000
Charged-device model (CDM), per JEDEC specification JESD22-C101 (2)
±500
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating ambient temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
POWER SUPPLY
VDD
Supply voltage
2.7
5.5
V
0
VDD
V
0
VDD
V
DIGITAL INPUTS
DIN
Digital input voltage
SCLK and SYNC
REFERENCE INPUT
VREF
Reference input voltage
AMPLIFIER FEEDBACK INPUT
VFB
Output amplifier feedback input
VO
V
TEMPERATURE RANGE
TA
Operating ambient temperature
–40
105
°C
6.4 Thermal Information
DAC8550
THERMAL METRIC
(1)
DGK (VSSOP)
UNIT
8 PINS
RθJA
Junction-to-ambient thermal resistance
206
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
44
°C/W
RθJB
Junction-to-board thermal resistance
94.2
°C/W
ψJT
Junction-to-top characterization parameter
10.2
°C/W
ψJB
Junction-to-board characterization parameter
92.7
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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6.5 Electrical Characteristics
VDD = 2.7 V to 5.5 V, –40°C to 105°C range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
STATIC PERFORMANCE (1)
Resolution
EL
Relative accuracy
ED
Differential nonlinearity
16
Measured by line passing through codes
–32283 and 32063 at VREF = 5 V, codes
–31798 and 31358 at VREF = 2.5 V
Bits
DAC8550
±16
DAC8550B
±12
LSB
2.5 V ≤ VREF ≤ 5.5 V, 0°C ≤ TA ≤ 105°C
±1
LSB
4.2 V < VREF ≤ 5.5 V, -40°C ≤ TA ≤ 105°C
±1
LSB
2.5 V ≤ VREF ≤ 4.2 V, -40°C ≤ TA ≤ 0°C
±2
LSB
EO
Zero-code error
Measured by line passing through codes –32283 and 32063
±2
±12
mV
EFS
Full-scale error
Measured by line passing through codes –32283 and 32063
±0.05%
±0.5%
mV
EG
Gain error
Measured by line passing through codes –32283 and 32063
±0.02%
±0.2%
PSRR
mV
Zero-code error drift
±5
μV/°C
Gain temperature coefficient
±1
ppm of
FSR/°C
Power-supply rejection ratio
RL = 2 kΩ, CL = 200 pF
0.75
mV/V
OUTPUT CHARACTERISTICS (2)
VO
Output voltage range
tSD
Output voltage settling time
SR
Slew rate
Capacitive load stability
zO
0
To ±0.003% FSR, 1200h to 8D00h, RL = 2 kΩ, 0 pF < CL < 200 pF
VREF
8
RL = 2 kΩ, CL = 500 pF
V
10
μs
12
1.8
RL = ∞
V/μs
470
RL = 2 kΩ
pF
1000
Code change glitch impulse
1 LSB change around major carry
0.1
nV-s
Digital feedthrough
SCLK toggling, FSYNC high
0.1
nV-s
DC output impedance
At mid-code input
IOS
Short-circuit current
tON
Power-up time
Ω
1
VDD = 5 V
50
VDD = 3 V
20
Coming out of power-down mode, VDD = 5 V
2.5
Coming out of power-down mode, VDD = 3 V
5
mA
μs
AC PERFORMANCE
SNR
Signal-to-noise ratio
BW = 20 kHz, VDD = 5 V, fOUT = 1 kHz,
1st 19 harmonics removed for SNR calculation
95
dB
THD
Total harmonic distortion
BW = 20 kHz, VDD = 5 V, fOUT = 1 kHz,
1st 19 harmonics removed for SNR calculation
–85
dB
SFDR
Spurious-free dynamic range
BW = 20 kHz, VDD = 5 V, fOUT = 1 kHz,
1st 19 harmonics removed for SNR calculation
87
dB
SINAD
Signal-to-noise and distortion
BW = 20 kHz, VDD = 5 V, fOUT = 1 kHz,
1st 19 harmonics removed for SNR calculation
84
dB
REFERENCE INPUT
VREF
Reference voltage
II(REF)
Reference current input range
zI(REF)
Reference input impedance
LOGIC INPUTS
0
40
75
VREF = VDD = 3.6 V
30
45
125
VIL
Low-level input voltage
VIH
High-level input voltage
6
μA
kΩ
±1
μA
3 V ≤ VDD ≤ 5.5 V
0.3 × VDD
2.7 V ≤ VDD < 3 V
0.1 × VDD
3 V ≤ VDD ≤ 5.5 V
0.7 × VDD
2.7 V ≤ VDD < 3 V
0.9 × VDD
Pin capacitance
(2)
V
(2)
Input current
(1)
VDD
VREF = VDD = 5 V
V
V
3
pF
Linearity calculated using a reduced code range –32283 and 32063 at VREF = 5V, codes –31798 and 31358 at VREF = 2.5V; output
unloaded, 100mV headroom between reference and supply.
Specified by design and characterization, not production tested.
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Electrical Characteristics (continued)
VDD = 2.7 V to 5.5 V, –40°C to 105°C range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
Normal mode, input code equals midVDD = 3.6 V to 5.5 V
scale, no load, does not include reference
VDD = 2.7 V to 3.6 V
current, VIH = VDD, VIL = GND
160
250
140
240
VDD = 3.6 V to 5.5 V
0.2
2
VDD = 2.7 V to 3.6 V
0.05
2
UNIT
POWER REQUIREMENTS
IDD
Supply current
All power-down modes,
VIH = VDD, VIL = GND
μA
POWER EFFICIENCY
IOUT/IDD
ILOAD = 2 mA, VDD = 5 V
89%
6.6 Timing Characteristics
VDD = 2.7 V to 5.5 V, all specifications –40°C to 105°C (unless otherwise noted) (1) (2)
PARAMETER
TEST CONDITIONS
t1 (3)
SCLK cycle time
t2
SCLK HIGH time
t3
SCLK LOW time
t4
SYNC to SCLK rising edge setup time
t5
Data setup time
t6
Data hold time
t7
24th SCLK falling edge to SYNC rising edge
t8
Minimum SYNC HIGH time
t9
24th SCLK falling edge to SYNC falling edge
(1)
(2)
(3)
MIN
VDD = 2.7 V to 3.6 V
50
VDD = 3.6 V to 5.5 V
33
VDD = 2.7 V to 3.6 V
13
VDD = 3.6 V to 5.5 V
13
VDD = 2.7 V to 3.6 V
22.5
VDD = 3.6 V to 5.5 V
13
VDD = 2.7 V to 3.6 V
0
VDD = 3.6 V to 5.5 V
0
VDD = 2.7 V to 3.6 V
5
VDD = 3.6 V to 5.5 V
5
VDD = 2.7 V to 3.6 V
4.5
VDD = 3.6 V to 5.5 V
4.5
VDD = 2.7 V to 3.6 V
0
VDD = 3.6 V to 5.5 V
0
VDD = 2.7 V to 3.6 V
50
VDD = 3.6 V to 5.5 V
33
VDD = 2.7 V to 5.5 V
100
TYP
MAX
UNIT
ns
ns
ns
ns
ns
ns
ns
ns
ns
All input signals are specified with tR = tF = 5 ns (10% to 90% of VDD) and timed from a voltage level of (VIL + VIH) / 2.
See Figure 1.
Maximum SCLK frequency is 30 MHz at VDD = 3.6 V to 5.5 V and 20 MHz at VDD = 2.7 V to 3.6 V.
t9
t1
SCLK
1
24
t8
t3
t4
t2
t7
SYNC
t6
t5
DIN
DB23
DB0
DB23
Figure 1. Serial Write Operation
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6.7 Typical Characteristics
6.7.1 VDD = 5 V
at TA = 25°C, unless otherwise noted
6
4
2
0
-2
-4
-6
LE (LSB)
VDD = 5V, VREF = 4.99V
1.0
1.0
0.5
0.5
DLE (LSB)
DLE (LSB)
LE (LSB)
6
4
2
0
-2
-4
-6
0
-0.5
-1.0
0
-0.5
-1.0
0
8192
16384 24576 32768 40960 49152
Digital Input Code
57344 65536
0
Figure 2. Linearity Error and Differential Linearity Error
vs Digital Input Code (–40°C)
8192
16384 24576 32768 40960 49152
Digital Input Code
57344 65536
Figure 3. Linearity Error and Differential Linearity Error
vs Digital Input Code
10
VDD = 5V
VREF = 4.99V
VDD = 5V, VREF = 4.99V
5
Error (mV)
LE (LSB)
6
4
2
0
-2
-4
-6
1.0
DLE (LSB)
VDD = 5V, VREF = 4.99V
0.5
0
0
-0.5
-5
-1.0
0
8192
16384 24576 32768 40960 49152
Digital Input Code
57344 65536
0
-40
40
80
120
Temperature (°C)
Figure 4. Linearity Error and Differential Linearity Error
vs Digital Input Code (105°C)
Figure 5. Zero-Scale Error vs Temperature
0
6
VDD = 5V
VREF = 4.99V
5
DAC Loaded with FFFFh
VOUT (mV)
Error (mV)
4
-5
3
VDD = 5.5V
VREF = VDD - 10mV
2
1
DAC Loaded with 0000h
0
-10
-40
8
0
40
80
120
0
2
4
6
8
Temperature (°C)
I(SOURCE/SINK) (mA)
Figure 6. Full-Scale Error vs Temperature
Figure 7. Source and Sink Current Capability
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VDD = 5 V (continued)
at TA = 25°C, unless otherwise noted
300
250
VDD = VREF = 5V
250
VREF = VDD = 5V
200
IDD (mA)
IDD (mA)
200
Reference Current Included
150
150
100
100
50
50
0
0
0
-40
8192 16384 24576 32768 40960 49152 57344 65536
50
80
110
Temperature (°C)
Figure 8. Supply Current vs Digital Input Code
Figure 9. Power-Supply Current vs Temperature
1.0
300
VREF = VDD
Reference Current Included, No Load
280
Power-Down Current (mA)
260
240
IDD (mA)
20
-10
Digital Input Code
220
200
180
160
140
VREF = VDD
0.8
0.6
0.4
0.2
120
0
100
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
2.7
3.1
3.5
4.3
4.7
5.1
5.5
VDD (V)
VDD (V)
Figure 10. Supply Current vs Supply Voltage
Figure 11. Power-Down Current vs Supply Voltage
1800
TA = 25°C, SCL Input (all other inputs = GND)
VDD = VREF = 5.5V
1600
Trigger Pulse 5V/div
1400
IDD (mA)
1200
1000
VDD = 5V
VREF = 4.096V
From Code: D000
To Code: FFFF
800
600
Rising Edge
1V/div
400
200
0
Zoomed Rising Edge
1mV/div
Time (2ms/div)
0
1
2
3
4
5
5V
VLOGIC (V)
Figure 12. Supply Current vs Logic Input Voltage
Figure 13. Full-Scale Settling Time: Rising Edge
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VDD = 5 V (continued)
at TA = 25°C, unless otherwise noted
Trigger Pulse 5V/div
Trigger Pulse 5V/div
VDD = 5V
VREF = 4.096V
From Code: FFFF
To Code: 0000
VDD = 5V
VREF = 4.096V
From Code: 4000
To Code: CFFF
Rising
Edge
1V/div
Falling
Edge
1V/div
Zoomed Falling Edge
1mV/div
Zoomed Rising Edge
1mV/div
Time (2ms/div)
Time (2ms/div)
5V
5V
Figure 14. Full-Scale Settling Time: Falling Edge
Figure 15. Half-Scale Settling Time: Rising Edge
VDD = 5V
VREF = 4.096V
From Code: CFFF
To Code: 4000
Falling
Edge
1V/div
VOUT (500mV/div)
Trigger Pulse 5V/div
VDD = 5V
VREF = 4.096V
From Code: 7FFF
To Code: 8000
Glitch: 0.08nV-s
Zoomed Falling Edge
1mV/div
Time (2ms/div)
Time (400ns/div)
5V
5V
VDD = 5V
VREF = 4.096V
From Code: 8000
To Code: 7FFF
Glitch: 0.16nV-s
Measured Worst Case
Figure 17. Glitch Energy: Rising Edge
VOUT (500mV/div)
VOUT (500mV/div)
Figure 16. Half-Scale Settling Time: Falling Edge
VDD = 5V
VREF = 4.096V
From Code: 8000
To Code: 8010
Glitch: 0.04nV-s
Time (400ns/div)
5V
Time (400ns/div)
1-LSB Step
5V
Figure 18. Glitch Energy: Falling Edge
10
1-LSB Step
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16-LSB Step
Figure 19. Glitch Energy: Rising Edge
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VDD = 5 V (continued)
at TA = 25°C, unless otherwise noted
VOUT (5mV/div)
VOUT (500mV/div)
VDD = 5V
VREF = 4.096V
From Code: 8010
To Code: 8000
Glitch: 0.08nV-s
VDD = 5V
VREF = 4.096V
From Code: 8000
To Code: 80FF
Glitch: Not Detected
Theoretical Worst Case
Time (400ns/div)
5V
Time (400ns/div)
16-LSB Step
5V
Figure 20. Glitch Energy: Falling Edge
Figure 21. Glitch Energy: Rising Edge
-40
VDD = 5V
VREF = 4.096V
From Code: 80FF
To Code: 8000
Glitch: Not Detected
Theoretical Worst Case
VDD = 5V
VREF = 4.9V
-1dB FSR Digital Input
fS = 1MSPS
Measurement Bandwidth = 20kHz
-50
-60
THD (dB)
VOUT (5mV/div)
256-LSB Step
-70
THD
-80
-90
2nd Harmonic
5V
0
256-LSB Step
3
4
5
VDD = 5V
VREF = 4.096V
fOUT = 1kHz
f
= 1MSPS
-10
-30
CLK
Gain (dB)
SNR (dB)
94
2
Figure 23. Total Harmonic Distortion vs Output Frequency
VREF = VDD = 5V
-1dB FSR Digital Input
fS = 1MSPS
Measurement Bandwidth = 20kHz
96
1
fOUT (kHz)
Figure 22. Glitch Energy: Falling Edge
98
3rd Harmonic
-100
Time (400ns/div)
92
90
-50
-70
88
-90
86
-110
84
-130
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.5
0
5
10
15
20
Frequency (kHz)
fOUT (kHz)
Figure 24. Signal-to-Noise Ratio vs Output Frequency
Figure 25. Power Spectral Density
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VDD = 5 V (continued)
at TA = 25°C, unless otherwise noted
350
VDD = 5V
VREF = 4.99V
Code = 7FFFh
No Load
Voltage Noise (nV/ÖHz)
300
250
200
150
100
100
1k
10k
100k
Frequency (Hz)
Figure 26. Output Noise Density
6.7.2 VDD = 2.7 V
6
4
2
0
-2
-4
-6
LE (LSB)
VDD = 2.7V, VREF = 2.69V
1.0
0.5
0.5
0
-0.5
-1.0
8192
16384 24576 32768 40960 49152
Digital Input Code
-0.5
0
6
4
2
0
-2
-4
-6
8192
16384 24576 32768 40960 49152
Digital Input Code
57344 65536
Figure 28. Linearity Error and Differential Linearity Error
vs Digital Input Code
10
VDD = 2.7V
VREF = 2.69V
VDD = 2.7V, VREF = 2.69V
5
Error (mV)
LE (LSB)
0
57344 65536
Figure 27. Linearity Error and Differential Linearity Error
vs Digital Input Code (–40°C)
1.0
DLE (LSB)
VDD = 2.7V, VREF = 2.69V
-1.0
0
0.5
0
0
-0.5
-5
-1.0
0
8192
16384 24576 32768 40960 49152
Digital Input Code
57344 65536
0
-40
40
80
120
Temperature (°C)
Figure 29. Linearity Error and Differential Linearity Error
vs Digital Input Code (105°C)
12
6
4
2
0
-2
-4
-6
1.0
DLE (LSB)
DLE (LSB)
LE (LSB)
at TA = 25°C, unless otherwise noted
Figure 30. Zero-Scale Error vs Temperature
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VDD = 2.7 V (continued)
at TA = 25°C, unless otherwise noted
5
3.0
VDD = 2.7V
VREF = 2.69V
2.5
DAC Loaded with FFFFh
0
VOUT (mV)
Error (mV)
2.0
1.5
VDD = 2.7V
VREF = VDD - 10mV
1.0
-5
0.5
DAC Loaded with 0000h
0
-10
0
-40
40
80
120
0
4
6
8
10
I(SOURCE/SINK) (mA)
Figure 31. Full-Scale Error vs Temperature
Figure 32. Source and Sink Current Capability
180
250
VDD = VREF = 2.7V
160
2
Temperature (°C)
VREF = VDD = 2.7V
200
140
Reference Current Included
IDD (mA)
IDD (mA)
120
100
80
150
100
60
40
50
20
0
0
8192 16384 24576 32768 40960 49152 57344 65536
0
-40
-10
20
50
80
110
Digital Input Code
Temperature (°C)
Figure 33. Supply Current vs Digital Input Code
Figure 34. Power-Supply Current vs Temperature
800
TA = 25°C, SCL Input (all other inputs = GND)
VDD = VREF = 2.7V
700
Trigger Pulse 2.7V/div
600
Rising
Edge
0.5V/div
IDD (mA)
500
400
VDD = 2.7V
VREF = 2.5V
From Code: 0000
To Code: FFFF
300
200
Zoomed Rising Edge
1mV/div
100
0
0
0.5
1.0
1.5
2.0
Time (2ms/div)
2.5 2.7
2.7 V
VLOGIC (V)
Figure 35. Supply Current vs Logic Input Voltage
Figure 36. Full-Scale Settling Time: Rising Edge
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VDD = 2.7 V (continued)
at TA = 25°C, unless otherwise noted
Trigger Pulse 2.7V/div
Trigger Pulse 2.7V/div
VDD = 2.7V
VREF = 2.5V
From Code: FFFF
To Code: 0000
Zoomed Falling Edge
1mV/div
Falling
Edge
0.5V/div
VDD = 2.7V
VREF = 2.5V
From Code: 4000
To Code: CFFF
Rising
Edge
0.5V/div
Zoomed Rising Edge
1mV/div
Time (2ms/div)
Time (2ms/div)
2.7 V
2.7 V
Figure 37. Full-Scale Settling Time: Falling Edge
Figure 38. Half-Scale Settling Time: Rising Edge
VDD = 2.7V
VREF = 2.5V
From Code: CFFF
To Code: 4000
Falling
Edge
0.5V/div
VOUT (200mV/div)
Trigger Pulse 2.7V/div
VDD = 2.7V
VREF = 2.5V
From Code: 7FFF
To Code: 8000
Glitch: 0.08nV-s
Zoomed Falling Edge
1mV/div
Time (2ms/div)
Time (400ns/div)
2.7 V
2.7 V
VDD = 2.7V
VREF = 2.5V
From Code: 8000
To Code: 7FFF
Glitch: 0.16nV-s
Measured Worst Case
Figure 40. Glitch Energy: Rising Edge
VOUT (200mV/div)
VOUT (200mV/div)
Figure 39. Half-Scale Settling Time: Falling Edge
VDD = 2.7V
VREF = 2.5V
From Code: 8000
To Code: 8010
Glitch: 0.04nV-s
Time (400ns/div)
2.7 V
Time (400ns/div)
1-LSB Step
2.7 V
Figure 41. Glitch Energy: Falling Edge
14
1-LSB Step
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16-LSB Step
Figure 42. Glitch Energy: Rising Edge
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VDD = 2.7 V (continued)
VOUT (200mV/div)
VDD = 2.7V
VREF = 2.5V
From Code: 8010
To Code: 8000
Glitch: 0.12nV-s
VOUT (5mV/div)
at TA = 25°C, unless otherwise noted
VDD = 2.7V
VREF = 2.5V
From Code: 8000
To Code: 80FF
Glitch: Not Detected
Theoretical Worst Case
Time (400ns/div)
2.7 V
Time (400ns/div)
16-LSB Step
2.7 V
Figure 43. Glitch Energy: Falling Edge
256-LSB Step
Figure 44. Glitch Energy: Rising Edge
VOUT (5mV/div)
VDD = 2.7V
VREF = 2.5V
From Code: 80FF
To Code: 8000
Glitch: Not Detected
Theoretical Worst Case
Time (400ns/div)
2.7 V
256-LSB Step
Figure 45. Glitch Energy: Falling Edge
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7 Detailed Description
7.1 Overview
The DAC8550 is a small, low-power, voltage output, single-channel, 16-bit DAC. The device is monotonic by
design, provides excellent linearity, and minimizes undesired code-to-code transient voltages. The DAC8550
uses a versatile, three-wire serial interface that operates at clock rates of up to 30 MHz and is compatible with
standard SPI, QSPI, Microwire, and digital signal processor (DSP) interfaces.
7.2 Functional Block Diagram
VDD
VFB
VREF
REF (+)
16-Bit DAC
VOUT
16
DAC Register
16
SYNC
PWB
Control
Shift Register
SCLK
Resistor
Network
DIN
GND
Copyright © 2016, Texas Instruments Incorporated
7.3 Feature Description
7.3.1 DAC Section
The architecture of the DAC8850 consists of a string DAC followed by an output buffer amplifier. Figure 46
shows the block diagram of the DAC architecture.
VREF
50kW
50kW
VFB
62kW
DAC
Register
VOUT
REF(+)
Resistor String
REF(-)
GND
Copyright © 2016, Texas Instruments Incorporated
Figure 46. DAC8550 Architecture
The input coding to the DAC8550 is 2's complement, so the ideal output voltage is given by Equation 1.
V
V
´D
VO = REF + REF
2
65536
where
•
D = decimal equivalent of the 2's complement code that is loaded to the DAC register
(1)
In Equation 1, D ranges from –32768 to 32767 where D = 0 is centered at VREF / 2.
16
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Feature Description (continued)
7.3.1.1 Resistor String
The resistor string section is shown in Figure 47. It is simply a string of resistors, each of value R. The code
loaded into the DAC register determines at which node on the string the voltage is tapped off to be fed into the
output amplifier by closing one of the switches connecting the string to the amplifier. Monotonicity is ensured
because of the string resistor architecture.
7.3.1.2 Output Amplifier
The output buffer amplifier is capable of generating rail-to-rail output voltages with a range of 0 V to VDD. It is
capable of driving a load of 2 kΩ in parallel with 1000 pF to GND. The source and sink capabilities of the output
amplifier can be seen in the Typical Characteristics. The slew rate is 1.8 V/μs with a full-scale setting time of 8 μs
with the output unloaded.
The inverting input of the output amplifier is brought out to the VFB pin. This architecture allows for better
accuracy in critical applications by tying the VFB point and the amplifier output together directly at the load. Other
signal conditioning circuitry may also be connected between these points for specific applications.
R
R
R
To Output
Amplifier
R
R
Figure 47. Resistor String
7.3.2 Power-On Reset
The DAC8550 contains a power-on reset circuit that controls the output voltage during power-up. On power-up,
the output voltages are set to midscale; they remain that way until a valid write sequence is made to the DAC.
The power-on reset is useful in applications where it is important to know the state of the output of the DAC while
it is in the process of powering up.
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7.4 Device Functional Modes
7.4.1 Power-Down Modes
The DAC8550 supports four separate modes of operation. These modes are programmable by setting two bits
(PD1 and PD0) in the control register. Table 1 shows how the state of the bits corresponds to the mode of
operation of the device.
Table 1. Operating Modes
PD1 (DB17)
PD0 (DB16)
0
0
Normal operation
OPERATING MODE
—
—
Power-down modes
0
1
Output typically 1 kΩ to GND
1
0
Output typically 100 kΩ to GND
1
1
High-Z
When both bits are set to 0, the device works normally with a typical current consumption of 200 μA at 5 V.
However, for the three power-down modes, the supply current falls to 200 nA at 5 V (50 nA at 3 V). Not only
does the supply current fall, but the output stage is also internally switched from the output of the amplifier to a
resistor network of known values. The advantage with this configuration is that the output impedance of the
device is known while in power-down mode. There are three different options. The output is connected internally
to GND through a 1-kΩ resistor, a 100-kΩ resistor, or it is left open-circuited (High-Z). The output stage is
illustrated in Figure 48.
VFB
Resistor
String
DAC
Amplifier
Power-Down
Circuitry
VOUT
Resistor
Network
Copyright © 2016, Texas Instruments Incorporated
Figure 48. Output Stage During Power-Down
All analog circuitry is shut down when the power-down mode is activated. However, the contents of the DAC
register are unaffected when in power-down. The time to exit power-down is typically 2.5 μs for VDD = 5 V, and 5
μs for VDD = 3 V. See the Typical Characteristics for more information.
7.5 Programming
7.5.1 Serial Interface
The DAC8550 has a 3-wire serial interface (SYNC, SCLK, and DIN), which is compatible with SPI, QSPI, and
Microwire interface standards, as well as most DSP interfaces. See Figure 1 for an example of a typical write
sequence.
The write sequence begins by bringing the SYNC line LOW. Data from the DIN line are clocked into the 24-bit
shift register on each falling edge of SCLK. The serial clock frequency can be as high as 30 MHz, making the
DAC8550 compatible with high-speed DSPs. On the 24th falling edge of the serial clock, the last data bit is
clocked in and the programmed function is excuted (that is, a change in DAC register contents and/or a change
in the mode of operation).
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Programming (continued)
At this point, the SYNC line may be kept LOW or brought HIGH. In either case, it must be brought HIGH for a
minimum of 33 ns before the next write sequence so that a falling edge of SYNC can initiate the next write
sequence. Since the SYNC buffer draws more current when the SYNC signal is HIGH than it does when it is
LOW, SYNC should be idled LOW between write sequences for lowest power operation of the part. As
mentioned above, it must be brought HIGH again just before the next write sequence.
7.5.2 Input Shift Register
The input shift register is 24 bits wide, as shown in Figure 49. The first six bits are unused bits. The next two bits
(PD1 and PD0) are control bits that control which mode of operation the part is in (normal mode or any one of
three power-down modes). For a more complete description of the various modes see Power-Down Modes. The
next 16 bits are the data bits. These bits are transferred to the DAC register on the 24th falling edge of SCLK.
23 22 21 20 19 18 17
16
15
14
13
12
11
10
Unused
PD1 PD0 D15 D14 D13 D12 D11 D10
9
D9
8
D8
7
D7
6
D6
5
D5
4
D4
3
D3
2
D2
1
D1
0
D0
Figure 49. DAC8550 Data Input Register Format
7.5.3 SYNC Interrupt
In a normal write sequence, the SYNC line is kept LOW for at least 24 falling edges of SCLK and the DAC is
updated on the 24th falling edge. However, if SYNC is brought HIGH before the 24th falling edge, it acts as an
interrupt to the write sequence. The shift register is reset and the write sequence is seen as invalid. Neither an
update of the DAC register contents nor a change in the operating mode occurs, as shown in Figure 50.
24th Falling Edge
24th Falling Edge
CLK
SYNC
DIN
DB23
DB80
DB23
DB80
Valid Write Sequence: Output Updates
on the 24th Falling Edge
Figure 50. SYNC Interrupt Facility
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The low-power consumption of the DAC8550 lends itself to applications such as loop-powered control where the
current dissipation of each device is critical. The low power consumption also allows the DAC8550 to be powered
using only a precision reference for increased accuracy. The low-power operation coupled with the ultra-low
power power-down modes also make the DAC8550 a great choice for battery and portable applications.
8.1.1 Bipolar Operation Using DAC8550
The DAC8550 has been designed for single-supply operation, but a bipolar output range is also possible using
the circuit in Figure 51. The circuit shown gives an output voltage range of ±VREF. Rail-to-rail operation at the
amplifier output is achievable using an OPA703 as the output amplifier. See CMOS, Rail-to-Rail, I/O Operational
Amplifier (SBOS180) for more information.
R2
10kW
V
REF
+6V
R1
10kW
OPA703
5V
VFB
VREF
10mF
DAC8550
VOUT
0.1mF
-6V
Three-Wire
Serial Interface
Copyright © 2016, Texas Instruments Incorporated
Figure 51. Bipolar Output Range
The output voltage for any input code is calculated with Equation 2 and Equation 3.
éæ V
æ R 2 öù
D ö æ R1 + R 2 ö
VO = êç REF + VREF ´
´ç
÷ - VREF ´ ç
÷ú
÷
65536 ø è R 1 ø
êëè 2
è R 1 ø ûú
where
•
•
•
D represents the input code in 2's complement (–32768 to 32767)
VREF = 5 V
R1 = R2 = 10 kΩ
VO = 10 ´
D
65536
(2)
(3)
Using this example, an output voltage range of ±5 V with 8000h corresponding to a –5-V output and 8FFFh
corresponding to a 5-V output can be achieved. Similarly, using VREF = 2.5 V, a ±2.5-V output voltage range can
be achieved.
20
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8.2 Typical Applications
8.2.1 Loop-Powered 2-Wire 4-mA to 20-mA Transmitter With XTR116
VREG
C2 || C3
Vref
0.1001 µF
V+
XTR116
V+
Regulator
Reference
C1
2.2 µF
U1
V+
R1
102.4 NŸ
Vref
DAC8550
R2
49.9 Ÿ
VOUT
V+
IIN
+
B
Q1
U2
R3
25.6 NŸ
±
Q1
RLIM
IRET
2475 Ÿ
25 Ÿ
E
IO
Return
Copyright © 2016, Texas Instruments Incorporated
Figure 52. Loop-Powered Transmitter
8.2.1.1 Design Requirements
This design is commonly referred to as a loop-powered, or 2-wire, 4-mA to 20-mA transmitter. The transmitter
has only two external input terminals: a supply connection and an output, or return, connection. The transmitter
communicates back to its host, typically a PLC analog input module, by precisely controlling the magnitude of its
return current. In order to conform to the 4-mA to 20-mA communication standard, the complete transmitter must
consume less than 4 mA of current. The DAC8550 enables the accurate control of the loop-current from 4 mA to
20 mA in 16-bit steps.
8.2.1.2 Detailed Design Procedure
Although it is possible to recreate the loop-powered circuit using discrete components, the XTR116 provides
simplicity and improved performance due to the matched internal resistors. The output current can be modified if
necessary by looking using Equation 4.
æ V ´ Code VREG
+
I OUT (Code) = ç refN
ç 2 ´ R3
R1
è
ö æ
ö
÷ ´ ç 1 + 2475 W ÷
÷ è
25 W ø
ø
(4)
For more details of this application, see 2-wire, 4-mA to 20-mA Transmitter, EMC/EMI Tested Reference Design
(TIDUAO7). It covers in detail the design of this circuit as well as how to protect it from EMC/EMI tests.
8.2.1.3 Application Curves
Total unadjusted error (TUE) is a good estimate for the performance of the output as shown in Figure 53. The
linearity of the output or INL is in Figure 54.
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Typical Applications (continued)
10
0.1
Integral Nonlinearity (LSBs)
Total Unadjusted Error (%FSR)
8
0.05
0
-0.05
6
4
2
0
-2
-4
-6
-8
-10
-0.1
0
10k
20k
30k
40k
Code
50k
0
60k 65535
10k
20k
D001
Figure 53. Total Unadjusted Error
30k
40k
Code
50k
60k 65535
D002
Figure 54. Integral Nonlineareity
8.2.2 Using REF02 as a Power Supply for DAC8550
+15V
+5V
REF02
285mA
SYNC
Three-Wire
Serial
Interface
SCLK
DAC8550
VOUT = 0V to 5V
DIN
Copyright © 2016, Texas Instruments Incorporated
Figure 55. REF02 as a Power Supply to the DAC8550
8.2.2.1 Design Requirements
Due to the extremely low supply current required by the DAC8550, an alternative option is to use a REF02 to
supply the required voltage to the device, as shown in Figure 55. See +5V Precision Voltage Reference
(SBVS003) for more information.
8.2.2.2 Detailed Design Procedure
This configuration is especially useful if the power supply is quite noisy or if the system supply voltages are at
some value other than 5 V. The REF02 outputs a steady supply voltage for the DAC8550. If the REF02 is used,
the current it needs to supply to the DAC8550 is 250 μA. This configuration is with no load on the output of the
DAC. When a DAC output is loaded, the REF02 also needs to supply the current to the load. The total typical
current required (with a 5-kΩ load on the DAC output) is calculated with Equation 5.
5V
200 µA +
= 1.2 mA
5 kW
(5)
The load regulation of the REF02 is typically 0.005%/mA, resulting in an error of 299 μV for the 1.2-mA current
drawn from it. This value corresponds to an 8.9-LSB error.
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8.3 System Examples
8.3.1 Microprocessor Interfacing
8.3.1.1 DAC8550 to 8051 Interface
See Figure 56 for a serial interface between the DAC8550 and a typical 8051-type microcontroller. The setup for
the interface is as follows: TXD of the 8051 drives SCLK of the DAC8550, while RXD drives the serial data line of
the device. The SYNC signal is derived from a bit-programmable pin on the port of the 8051. In this case, port
line P3.3 is used. When data are to be transmitted to the DAC8550, P3.3 is taken LOW. The 8051 transmits data
in 8-bit bytes; thus, only eight falling clock edges occur in the transmit cycle. To load data to the DAC, P3.3 is left
LOW after the first eight bits are transmitted, then a second write cycle is initiated to transmit the second byte of
data. P3.3 is taken HIGH following the completion of the third write cycle. The 8051 outputs the serial data in a
format that has the LSB first. The DAC8550 requires its data with the MSB as the first bit received. The 8051
transmit routine must therefore take this into account, and mirror the data as needed.
80C51/80L51(1)
DAC8550(1)
P3.3
SYNC
TXD
SCLK
RXD
DIN
NOTE: (1) Additional pins omitted for clarity.
Figure 56. DAC8550 to 80C51 or 80L51 Interface
8.3.1.2 DAC8550 to Microwire Interface
Figure 57 shows an interface between the DAC8550 and any Microwire-compatible device. Serial data are
shifted out on the falling edge of the serial clock and clocked into the DAC8550 on the rising edge of the SK
signal.
MicrowireTM
DAC8550(1)
CS
SYNC
SK
SCLK
SO
DIN
NOTE: (1) Additional pins omitted for clarity.
Figure 57. DAC8550 to Microwire Interface
8.3.1.3 DAC8550 to 68HC11 Interface
Figure 58 shows a serial interface between the DAC8550 and the 68HC11 microcontroller. SCK of the 68HC11
drives the SCLK of the DAC8550, while the MOSI output drives the serial data line of the DAC. The SYNC signal
is derived from a port line (PC7), similar to the 8051 diagram.
68HC11(1)
DAC8550(1)
PC7
SYNC
SCK
SCLK
MOSI
DIN
NOTE: (1) Additional pins omitted for clarity.
Figure 58. DAC8550 to 68HC11 Interface
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System Examples (continued)
The 68HC11 should be configured so that its CPOL bit is '0' and its CPHA bit is '1'. This configuration causes
data appearing on the MOSI output to be valid on the falling edge of SCK. When data are being transmitted to
the DAC, the SYNC line is held LOW (PC7). Serial data from the 68HC11 are transmitted in 8-bit bytes with only
eight falling clock edges occurring in the transmit cycle. (Data are transmitted MSB first.) In order to load data to
the DAC8550, PC7 is left LOW after the first eight bits are transferred, then a second and third serial write
operation are performed to the DAC. PC7 is taken HIGH at the end of this procedure.
9 Power Supply Recommendations
The DAC8550 can operate within the specified supply voltage range of 2.7 V to 5.5 V. The power applied to VDD
should be well-regulated and low-noise. Switching power supplies and dc/dc converters often have highfrequency glitches or spikes riding on the output voltage. In addition, digital components can create similar highfrequency spikes. This noise can easily couple into the DAC output voltage through various paths between the
power connections and analog output. In order to further minimize noise from the power supply, a strong
recommendation is to include a 1-μF to 10-μF capacitor and 0.1-μF bypass capacitor. The current consumption
on the VDD pin, the short-circuit current limit, and the load current for the device is listed in the Electrical
Characteristics. The power supply must meet the aforementioned current requirements.
10 Layout
10.1 Layout Guidelines
A precision analog component requires careful layout, adequate bypassing, and clean, well-regulated power
supplies.
The DAC8550 offers single-supply operation and is used often in close proximity with digital logic,
microcontrollers, microprocessors, and digital signal processors. The more digital logic present in the design and
the higher the switching speed, the more difficult it is to keep digital noise from appearing at the output.
Due to the single ground pin of the DAC8550, all return currents, including digital and analog return currents for
the DAC, must flow through a single point. Ideally, GND would be connected directly to an analog ground plane.
This plane would be separate from the ground connection for the digital components until they were connected at
the power-entry point of the system.
As with the GND connection, VDD should be connected to a 5-V power-supply plane or trace that is separate
from the connection for digital logic until they are connected at the power-entry point. In addition, a 1-μF to 10-μF
capacitor and 0.1-μF bypass capacitor are strongly recommended. In some situations, additional bypassing may
be required, such as a 100-μF electrolytic capacitor or even a Pi filter made up of inductors and capacitors, all
designed to essentially low-pass filter the 5-V supply, removing the high-frequency noise.
10.2 Layout Example
1
2
3
4
8
7
6
5
Figure 59. Layout Diagram
24
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Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: DAC8550
DAC8550
www.ti.com
SLAS476H – MARCH 2006 – REVISED JUNE 2017
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
• 2-wire, 4-mA to 20-mA Transmitter, EMC/EMI Tested Reference Design, TIDUAO7
• +5-V Precision Voltage Reference, SBVS003
• CMOS, Rail-to-Rail, I/O Operational Amplifier, SBOS180
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
SPI, QSPI are trademarks of Motorola, Inc.
Microwire is a trademark of National Semiconductor.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: DAC8550
25
PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
DAC8550IBDGKR
ACTIVE
VSSOP
DGK
8
2500
RoHS & Green
Call TI
Level-2-260C-1 YEAR
-40 to 105
D80
Samples
DAC8550IBDGKT
ACTIVE
VSSOP
DGK
8
250
RoHS & Green
Call TI
Level-2-260C-1 YEAR
-40 to 105
D80
Samples
DAC8550IDGKR
ACTIVE
VSSOP
DGK
8
2500
RoHS & Green
Call TI | NIPDAU
Level-2-260C-1 YEAR
-40 to 105
D80
Samples
DAC8550IDGKT
ACTIVE
VSSOP
DGK
8
250
RoHS & Green
Call TI | NIPDAU
Level-2-260C-1 YEAR
-40 to 105
D80
Samples
DAC8550IDGKTG4
ACTIVE
VSSOP
DGK
8
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 105
D80
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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