MAX5142EUB-T [MAXIM]
D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO10, MICRO MAX PACKAGE-10;
| 型号： | MAX5142EUB-T |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO10, MICRO MAX PACKAGE-10 |
| 文件： | 总12页 (文件大小：410K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1849; Rev 1; 5/01
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
General Description
Features
The MAX5141–MAX5144 are serial-input, voltage-output,
14-bit digital-to-analog converters (DACs) in tiny µMAX
packages, 50% smaller than comparable DACs in an
8-pin SO. They operate from low +3V (MAX5143/
MAX5144) or +5V (MAX5141/MAX5142) single supplies.
They provide 14-bit performance ( 1ꢀSꢁ ꢂIꢀ and DIꢀ)
over temperature without any adjustments. The DAC out-
put is unbuffered, resulting in a low supply current of
120µA and a low offset error of 2ꢀSꢁs.
o Miniature (3mm x 5mm) 8-Pin µMAX Package
o Low 120µA Supply Current
o Fast 1µs Settling Time
o 25MHz SPI/QSPI/MICROWIRE-Compatible Serial
Interface
o V
Range Extends to V
DD
REF
o +5V (MAX5141/MAX5142) or +3V
(MAX5143/MAX5144) Single-Supply Operation
The DAC output range is 0V to V
For bipolar opera-
REF.
tion, matched scaling resistors are provided in the
MAX5142/MAX5144 for use with an external precision op
o Full 14-Bit Performance Without Adjustments
o Unbuffered Voltage Output Directly Drives 60kΩ
amp (such as the MAX400), generating a
swing.
V
REF
output
Loads
o Power-On Reset Circuit Clears DAC Output to
Code 0 (MAX5141/MAX5143) or Code 8192
(MAX5142/MAX5144)
A 16-bit serial word is used to load data into the DAC
latch. The 25MHz, 3-wire serial interface is compatible
with SPꢂ™/QSPꢂ™/MꢂCROWꢂRE™, and can interface
directly with optocouplers for applications requiring isola-
tion. A power-on reset circuit clears the DAC output to
code 0 (MAX5141/MAX5143) or code 8192 (MAX5142/
MAX5144) when power is initially applied.
o Schmitt-Trigger Inputs for Direct Optocoupler
Interface
o Asynchronous CLR
A logic low on CLR asynchronously clears the DAC out-
put to code 0 (MAX5141/MAX5143) or code 8192
(MAX5142/MAX5144), independent of the serial interface.
Pin Configurations
The MAX5141/MAX5143 are available in 8-pin µMAX
packages and the MAX5142/MAX5144 are available in
10-pin µMAX packages.
TOP VIEW
GND
REF
CS
1
2
3
4
5
10
9
GND
1
2
3
4
8
7
6
5
REF
CS
V
DD
V
DD
Applications
High-Resolution and Gain Adjustment
ꢂndustrial Process Control
MAX5141
MAX5143
MAX5142
MAX5144
SCLK
DIN
8
RFB
INV
OUT
CLR
SCLK
DIN
7
CLR
OUT
6
Automated Test Equipment
µMAX
µMAX
Data-Acquisition Systems
Ordering Information
SUPPLY
PART
TEMP. RANGE
PIN-PACKAGE
INL (LSB)
OUTPUT SWING
RANGE (V)
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
8 µMAX
10 µMAX
8 µMAX
1
1
1
1
5
5
3
3
Unipolar
Bipolar
Unipolar
Bipolar
MAX5141EUA
MAX5142EUB
MAX5143EUA
MAX5144EUB
10 µMAX
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
ABSOLUTE MAXIMUM RATINGS
DD
V
to GND..............................................................-0.3V to +6V
Operating Temperature Ranges
CS, SCLK, DIN, CLR to GND ...................................-0.3V to +6V
REF to GND................................................-0.3V to (V + 0.3V)
MAX514_ EUA...................................................-40°C to +85°C
MAX514_ EUB...................................................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Maximum Die Temperature..............................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
DD
OUT, INV to GND .....................................................-0.3V to V
DD
RFB to INV...................................................................-6V to +6V
RFB to GND.................................................................-6V to +6V
Maximum Current into Any Pin............................................50mA
Continuous Power Dissipation (T = +70°C)
A
8-Pin µMAX (derate 4.5mW/°C above +70°C)...............362mW
10-Pin µMAX (derate 5.6mW/°C above +70°C).............444mW
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
DD
(V
= +3V (MAX5143/MAX5144) or +5V (MAX5141/MAX5142), V
= +2.5V, T = T
to T
, C = 10 F, GND = 0, R = ∞,
REF
A
MIN
MAX
L
p
L
unless otherwise noted. Typical values are at T = +25°C.)
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
STATIC PERFORMANCE—ANALOG SECTION
Resolution
N
14
Bits
LSB
Differential Nonlinearity
Integral Nonlinearity
Zero-Code Offset Error
Zero-Code Tempco
Gain Error (Note 1)
Gain-Error Tempco
DAC Output Resistance
DNL
INL
ZSE
Guaranteed monotonic
0.5
0.5
1
1
2
MAX514_
LSB
LSB
ZS
0.05
ppm/°C
LSB
TC
10
0.1
6.2
1
ppm/°C
kΩ
R
(Note 2)
OUT
R /R
FB INV
Bipolar Resistor Matching
%
0.03
20
Ratio error
Bipolar Zero Offset Error
Bipolar Zero Tempco
LSB
BZS
0.5
ppm/°C
TC
+2.7V ≤ V
+4.5V ≤ V
≤ +3.3V (MAX5143/MAX5144)
1
1
DD
PSR
Power-Supply Rejection
LSB
≤ +5.5V (MAX5141/MAX5142)
DD
Reference Input Range
V
R
(Note 3)
2.0
10
6
V
V
REF
DD
Unipolar mode
Bipolar mode
Reference Input Resistance
(Note 4)
kΩ
REF
DYNAMIC PERFORMANCE—ANALOG SECTION
Voltage-Output Slew Rate
Output Settling Time
DAC Glitch Impulse
SR
(Note 5)
To 1/2LSB of FS
15
1
V/µs
µs
Major-carry transition
7
nV-s
Code = 0000 hex; CS = V
;
DD
Digital Feedthrough
0.2
nV-s
SCLK, DIN = 0V to V
levels
DD
2
_______________________________________________________________________________________
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
ELECTRICAL CHARACTERISTICS (continued)
(V
= +3V (MAX5143/MAX5144) or +5V (MAX5141/MAX5142), V
= +2.5V, T = T
to T
, C = 10 F, GND = 0, RL = ∞,
DD
REF
A
MIN
MAX
L
p
unless otherwise noted. Typical values are at T = +25°C.)
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DYNAMIC PERFORMANCE—REFERENCE SECTION
Reference -3dB Bandwidth
Reference Feedthrough
Signal-to-Noise Ratio
BW
Code = 3FFF hex
1
1
MHz
Code = 0000 hex, V
= 1V
at 100kHz
mV
P-P
REF
P-P
SNR
92
70
170
dB
Code = 0000 hex
Code = 3FFF hex
Reference Input Capacitance
C
INREF
pF
STATIC PERFORMANCE—DIGITAL INPUTS
Input High Voltage
Input Low Voltage
Input Current
V
2.4
V
V
IH
V
0.8
1
IL
I
IN
µA
pF
V
Input Capacitance
Hysteresis Voltage
POWER SUPPLY
C
(Note 6)
3
10
IN
V
0.15
H
MAX5143/MAX5144
MAX5141/MAX5142
2.7
4.5
3.6
5.5
Positive Supply Range (Note 7)
Positive Supply Current
Power Dissipation
V
V
DD
I
All digital inputs at V
or GND
0.12
0.36
0.60
0.20
mA
mW
DD
DD
MAX5143/MAX5144
MAX5141/MAX5142
All digital inputs at
PD
V
DD
or GND
TIMING CHARACTERISTICS
(V
= +2.7V to +3.3V (MAX5143/MAX5144), V
= +4.5V to +5.5V (MAX5141/MAX5142), V
= +2.5V, GND = 0, CMOS inputs,
DD
REF
DD
T
A
= T
to T
, unless otherwise noted. Typical values are at T = +25°C.) (Figure 1)
MAX
A
MIN
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MHz
ns
SCLK Frequency
f
25
CLK
SCLK Pulse Width High
SCLK Pulse Width Low
CS Low to SCLK High Setup
CS High to SCLK High Setup
SCLK High to CS Low Hold
SCLK High to CS High Hold
DIN to SCLK High Setup
DIN to SCLK High Hold
CLR Pulse Width Low
t
20
20
15
15
35
20
15
0
CH
t
CL
ns
t
t
t
ns
CSS0
CSS1
ns
(Note 6)
ns
CSH0
CSH1
t
ns
t
ns
DS
t
ns
DH
t
20
ns
CLW
V
High to CS Low
DD
20
µs
(Power-Up Delay)
Note 1: Gain error tested at V
= +2.0V, +2.5V, and +3.0V (MAX5143/MAX5144) or V
= +2.0V, +2.5V, +3.0V, and +5.0V
REF
REF
(MAX5141/MAX5142).
Note 2: R tolerance is typically 20%.
OUT
Note 3: Min/max range guaranteed by gain-error test. Operation outside min/max limits will result in degraded performance.
Note 4: Reference input resistance is code dependent, minimum at 2155 hex in unipolar mode, 1155 hex in bipolar mode.
Note 5: Slew-rate value is measured from 10% to 90%.
Note 6: Guaranteed by design. Not production tested.
Note 7: Guaranteed by power-supply rejection test and Timing Characteristics.
_______________________________________________________________________________________
3
+3V/+5V, Serial-Input, Voltage-Output, 14-Bit
DACs
Typical Operating Characteristics
(V = +3V (MAX5143/MAX5144) or +5V (MAX5141/MAX5142), V
= +2.5V, T = T
to T
, GND = 0, R = ∞, unless otherwise
DD
REF
A
MIN
MAX
L
noted. Typical values are at T = +25°C.)
A
SUPPLY CURRENT
vs. REFERENCE VOLTAGE
SUPPLY CURRENT
vs. REFERENCE VOLTAGE
SUPPLY CURRENT vs. TEMPERATURE
0.12
0.11
0.10
0.09
0.08
0.07
0.12
0.11
0.10
0.09
0.08
0.07
0.06
0.05
0.150
V
= +5V
0.125
0.100
0.075
0.050
0.025
0
DD
V
= +3V
DD
0.06
0.05
V
= +3V
2.0
V
= +5V
DD
DD
0
0.5
1.0
1.5
2.5
3.0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
REFERENCE VOLTAGE (V)
-40
-40
-40
-15
10
35
60
85
85
85
REFERENCE VOLTAGE (V)
TEMPERATURE (°C)
DIFFERENTIAL NONLINEARITY
vs. TEMPERATURE
ZERO-CODE OFFSET ERROR
vs. TEMPERATURE
INTEGRAL NONLINEARITY
vs. TEMPERATURE
0.2
0.1
0.4
0.3
0.2
0.1
0
0.8
0.6
0.4
0.2
0
+DNL
+INL
0
-0.1
-0.2
-0.3
-0.4
-DNL
-0.1
-0.2
-0.2
-0.4
-INL
-40
-15
10
35
60
85
-15
10
35
60
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
DIFFERENTIAL NONLINEARITY vs. CODE
INTEGRAL NONLINEARITY vs. CODE
MAX5141 toc09
GAIN ERROR vs. TEMPERATURE
MAX5141 toc08
0.5
0.4
1.0
0.8
0
-0.05
-0.10
-0.15
-0.20
-0.25
-0.30
0.3
0.6
0.2
0.4
0.1
0.2
0.0
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.2
-0.4
-0.6
-0.8
-1.0
-15
10
35
60
0
2.50k 5.00k 7.50k 10.00k 12.50k 15.00k
CODE
0
2.50k 5.00k 7.50k 10.00k 12.50k 15.00k
CODE
TEMPERATURE (°C)
4
_______________________________________________________________________________________
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
Typical Operating Characteristics (continued)
(V = +3V (MAX5143/MAX5144) or +5V (MAX5141/MAX5142), V
= +2.5V, T = T
to T
, GND = 0, R = ∞, unless otherwise
MAX
L
DD
REF
A
MIN
noted. Typical values are at T = +25°C.)
A
REFERENCE CURRENT
vs. DIGITAL INPUT CODE
140
FULL-SCALE STEP RESPONSE
(FALLING)
FULL-SCALE STEP RESPONSE
(RISING)
MAX5141/44 toc11
MAX5141/44 toc12
120
100
80
60
40
20
0
CS
CS
2V/div
2V/div
A
A
OUT
2V/div
OUT
2V/div
C = 20pF
L
C = 20pF
L
0
5k
10k
15k
20k
400ns/div
400ns/div
INPUT CODE
MAJOR-CARRY GLITCH
(RISING)
MAJOR-CARRY GLITCH
(FALLING)
DIGITAL FEEDTHROUGH
MAX5141/44 toc15
MAX5141/44 toc13
MAX5141/44 toc14
CS
1V/div
CS
1V/div
D
IN
2V/div
A
A
A
OUT
10mV/div
OUT
20mV/div
OUT
20mV/div
C = 20pF
L
C = 20pF
L
50ns/div
200ns/div
200ns/div
INTEGRAL NONLINEARITY vs.
REFERENCE VOLTAGE
UNIPOLAR POWER-ON GLITCH
(REF = V
)
DD
MAX5141/44 toc17
0.70
0.65
0.60
0.55
0.50
0.45
0.40
V
DD
2V/div
V
OUT
10mV/div
50ms/div
2.0
2.5
3.0
3.5
4.0
4.5
5.0
REFERENCE VOLTAGE (V)
_______________________________________________________________________________________
5
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
Pin Descriptions
PIN
NAME
FUNCTION
MAX5141
MAX5143
MAX5142
MAX5144
1
2
3
4
1
2
3
4
REF
CS
Voltage Reference Input
Chip-Select Input
SCLK
DIN
Serial Clock Input. Duty cycle must be between 40% and 60%.
Serial Data Input
Clear Input. Logic low asynchronously clears the DAC to code 0
(MAX5141/MAX5143) or code 8192 (MAX5142/MAX5144).
5
6
5
6
7
CLR
OUT
INV
DAC Output Voltage
Junction of Internal Scaling Resistors. Connect to external op amp’s inverting input in
bipolar mode.
—
—
7
8
9
RFB
Feedback Resistor. Connect to external op amp’s output in bipolar mode.
Supply Voltage. Use +3V for MAX5143/MAX5144 and +5V for MAX5141/MAX5142.
Ground
V
DD
8
10
GND
t
t
CSH1
LDACS
CS
t
CSHO
t
CSS1
t
t
t
CL
CSSO
CH
SCLK
t
DH
t
DS
D13
D12
S0
DIN
Figure 1. Timing Diagram
6
_______________________________________________________________________________________
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
+2.5V
MAX6166
+3V/+5V
1µF
0.1µF
0.1µF
V
REF
DD
MC68XXXX
UNIPOLAR
OUT
CS
PCS0
MOSI
MAX495
EXTERNAL OP AMP
MAX5141
MAX5142
MAX5143
MAX5144
OUT
DIN
SCLK
CLR
SCLK
IC1
(GND)
GND
Figure 2a. Typical Operating Circuit—Unipolar Output
+2.5V
MAX6166
+3V/+5V
0.1µF
V
1µF
0.1µF
+5V
RFB
MC68XXXX
REF
DD
R
INV
PCS0
MOSI
SCLK
IC1
CS
R
INV
FB
BIPOLAR
OUT
EXTERNAL OP AMP
MAX400
DIN
OUT
SCLK
MAX5142
MAX5144
-5V
CLR
(GND)
GND
Figure 2b. Typical Operating Circuit—Bipolar Output
The MAX5141–MAX5144 are composed of two
matched DAC sections, with a 10-bit inverted R-2R
DAC forming the ten LSBs and the four MSBs derived
from 15 identically matched resistors. This architecture
allows the lowest glitch energy to be transferred to the
DAC output on major-carry transitions. It also lowers the
DAC output impedance by a factor of eight compared
Detailed Description
The MAX5141–MAX5144 voltage-output, 14-bit digital-
to-analog converters (DACs) offer full 14-bit perfor-
mance with less than 1LSB integral linearity error and
less than 1LSB differential linearity error, thus ensuring
monotonic performance. Serial data transfer minimizes
the number of package pins required.
_______________________________________________________________________________________
7
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
to a standard R-2R ladder, allowing unbuffered opera-
tion in medium-load applications.
applied. This ensures that unwanted DAC output volt-
ages will not occur immediately following a system
power-up, such as after a loss of power.
The MAX5142/MAX5144 provide matched bipolar offset
resistors, which connect to an external op amp for bipo-
lar output swings (Figure 2b).
Applications Information
Reference and Ground Inputs
Digital Interface
The MAX5141–MAX5144 digital interface is a standard
3-wire connection compatible with SPI/QSPI/
MICROWIRE interfaces. The chip-select input (CS)
frames the serial data loading at the data-input pin
(DIN). Immediately following CS’s high-to-low transition,
the data is shifted synchronously and latched into the
input register on the rising edge of the serial clock input
(SCLK). After 16 bits (14 data bits, plus two subbits set
to zero) have been loaded into the serial input register,
it transfers its contents to the DAC latch on CS’s low-to-
high transition (Figure 3). Note that if CS is not kept low
during the entire 16 SCLK cycles, data will be corrupt-
ed. In this case, reload the DAC latch with a new 16-bit
word.
The MAX5141–MAX5144 operate with external voltage
references from +2V to V , and maintain 14-bit perfor-
DD
mance if certain guidelines are followed when selecting
and applying the reference. Ideally, the reference’s
temperature coefficient should be less than 0.5ppm/°C to
maintain 14-bit accuracy to within 1LSB over the -40°C to
+85°C extended temperature range. Since this converter
is designed as an inverted R-2R voltage-mode DAC, the
input resistance seen by the voltage reference is code
dependent. In unipolar mode, the worst-case input-resis-
tance variation is from 11.5kΩ (at code 2155 hex) to
200kΩ (at code 0000 hex). The maximum change in load
current for a +2.5V reference is +2.5V / 11.5kΩ = 217µA;
therefore, the required load regulation is 28ppm/mA for a
maximum error of 0.1LSB. This implies a reference out-
put impedance of less than 72mΩ. In addition, the sig-
nal-path impedance from the voltage reference to the
reference input must be kept low because it contributes
directly to the load-regulation error.
Clearing the DAC
A 20ns (min) logic low pulse on CLR asynchronously
clears the DAC buffer to code 0 in the MAX5141/
MAX5143 and to code 8192 in the MAX5142/MAX5144.
The requirement for a low-impedance voltage reference
is met with capacitor bypassing at the reference inputs
and ground. A 0.1µF ceramic capacitor with short leads
between REF and GND provides high-frequency
bypassing. A surface-mount ceramic chip capacitor is
preferred because it has the lowest inductance. An
additional 1µF between REF and GND provides low-fre-
quency bypassing. A low-ESR tantalum, film, or organic
semiconductor capacitor works well. Leaded capaci-
tors are acceptable because impedance is not as criti-
External Reference
The MAX5141–MAX5144 operate with external voltage
references from +2V to V . The reference voltage
DD
determines the DAC’s full-scale output voltage.
Power-On Reset
The power-on reset circuit sets the output of the
MAX5141/MAX5143 to code 0 and the output of the
MAX5142/MAX5144 to code 8192 when V
is first
DD
CS
DAC
UPDATED
SCLK
SUB-BITS
DIN
D13 D12 D11 D10 D9 D8 D7 D6
MSB
D5 D4 D3 D2 D1 D0 S1 S0
LSB
Figure 3. MAX5141–MAX5144 3-Wire Interface Timing Diagram
8
_______________________________________________________________________________________
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
cal at lower frequencies. The circuit can benefit from
the DAC output resistance, which results in a gain error.
To contribute less than 1/2LSB of gain error, the input
resistance typically must be greater than:
even larger bypassing capacitors, depending on the
stability of the external reference with capacitive load-
ing.
6.25kΩ × 215 = 205MΩ
Unbuffered Operation
Unbuffered operation reduces power consumption as
well as offset error contributed by the external output
buffer. The R-2R DAC output is available directly at
The settling time is affected by the buffer input capaci-
tance, the DAC’s output capacitance, and PC board
capacitance. The typical DAC output voltage settling
time is 1µs for a full-scale step. Settling time can be sig-
nificantly less for smaller step changes. Assuming a
single time-constant exponential settling response, a
full-scale step takes 10.4 time constants to settle to
within 1/2LSB of the final output voltage. The time con-
stant is equal to the DAC output resistance multiplied
by the total output capacitance. The DAC output
capacitance is typically 10pF. Any additional output
capacitance increases the settling time.
OUT, allowing 14-bit performance from +V
to GND
REF
without degradation at zero scale. The DAC’s output
impedance is also low enough to drive medium loads
(R > 60kΩ) without degradation of INL or DNL; only
L
the gain error is increased by externally loading the
DAC output.
External Output Buffer Amplifier
The requirements on the external output buffer amplifier
change whether the DAC is used in unipolar or bipolar
operational mode. In unipolar mode, the output amplifi-
er is used in a voltage-follower connection. In bipolar
mode (MAX5142/MAX5144 only), the amplifier operates
with the internal scaling resistors (Figure 2b). In each
mode, the DAC’s output resistance is constant and is
independent of input code; however, the output amplifi-
er’s input impedance should still be as high as possible
to minimize gain errors. The DAC’s output capacitance
is also independent of input code, thus simplifying sta-
bility requirements on the external amplifier.
The external buffer amplifier’s gain-bandwidth product
is important because it increases the settling time by
adding another time constant to the output response.
The effective time constant of two cascaded systems,
each with a single time-constant response, is approxi-
mately the root square sum of the two time constants.
The DAC output’s time constant is 1µs / 10.4 = 96ns,
ignoring the effect of additional capacitance. If the time
constant of an external amplifier with 1MHz bandwidth
is 1 / 2π (1MHz) = 159ns, then the effective time con-
stant of the combined system is:
In bipolar mode, a precision amplifier operating with
dual power supplies (such as the MAX400) provides
the
V
output range. In single-supply applications,
REF
2
2
96ns + 159ns
= 186ns
(
)
(
)
precision amplifiers with input common-mode ranges
including GND are available; however, their output
swings do not normally include the negative rail (GND)
without significant degradation of performance. A sin-
gle-supply op amp, such as the MAX495, is suitable if
the application does not use codes near zero.
This suggests that the settling time to within 1/2LSB of
the final output voltage, including the external buffer
✕
amplifier, will be approximately 10.4 186ns = 1.93µs.
Digital Inputs and Interface Logic
The digital interface for the 14-bit DAC is based on a
3-wire standard that is compatible with SPI, QSPI, and
MICROWIRE interfaces. The three digital inputs (CS,
DIN, and SCLK) load the digital input data serially into
the DAC.
Since the LSBs for a 14-bit DAC are extremely small
(152.6µV for V
= +2.5V), pay close attention to the
REF
external amplifier’s input specification. The input offset
voltage can degrade the zero-scale error and might
require an output offset trim to maintain full accuracy if
the offset voltage is greater than 1/2LSB. Similarly, the
input bias current multiplied by the DAC output resis-
tance (typically 6.25kΩ) contributes to zero-scale error.
Temperature effects also must be taken into considera-
tion. Over the -40°C to +85°C extended temperature
range, the offset voltage temperature coefficient (refer-
enced to +25°C) must be less than 0.95µV/°C to add
less than 1/2LSB of zero-scale error. The external
amplifier’s input resistance forms a resistive divider with
A 20ns (min) logic low pulse to CLR clears the data in
the DAC buffer.
All of the digital inputs include Schmitt-trigger buffers to
accept slow-transition interfaces. This means that opto-
couplers can interface directly to the MAX5141–
MAX5144 without additional external logic. The digital
inputs are compatible with TTL/CMOS-logic levels.
_______________________________________________________________________________________
9
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
Unipolar Configuration
Table 1. Unipolar Code Table
Figure 2a shows the MAX5141–MAX5144 configured for
unipolar operation with an external op amp. The op amp
is set for unity gain, and Table 1 lists the codes for this
circuit. Bipolar MAX5142/MAX5144 can also be used in
unipolar configuration by connecting RFB and INV to
REF. This allows the DAC to power up to midscale.
DAC LATCH CONTENTS
MSB LSB
1111 1111 1111 11
ANALOG OUTPUT, V
OUT
✕
V
V
(16,383 / 16,384)
(8192 / 16,384) =
(1 / 16,384)
REF
1/
✕
✕
V
1000 0000 0000 00
0000 0000 0000 01
REF
REF
2
V
REF
Bipolar Configuration
Figure 2b shows the MAX5141–MAX5144 configured
for bipolar operation with an external op amp. The op
Table 2. Bipolar Code Table
amp is set for unity gain with an offset of -1/2V
.
REF
DAC LATCH CONTENTS
Table 2 shows the offset binary codes for this circuit
(less than 0.25 inches).
ANALOG OUTPUT, V
OUT
MSB
LSB
✕
+V
+V
0V
-V
(8191 / 8192)
1111 1111 1111 11
REF
Power-Supply Bypassing and
Ground Management
✕
(1 / 8192)
1000 0000 0000 01
1000 0000 0000 00
0111 1111 1111 11
0000 0000 0000 00
REF
Bypass V
with a 0.1µF ceramic capacitor connected
DD
DD
between V
and GND. Mount the capacitor with short
leads close to the device (less than 0.25 inches).
✕
(1 / 8192)
REF
REF
✕
-V
(8192 / 8192) = -V
REF
Functional Diagrams
V
V
DD
DD
RFB
INV
MAX5141
MAX5143
MAX5142
MAX5144
REF
CS
REF
CS
OUT
OUT
14-BIT DAC
14-BIT DAC
14-BIT DATA LATCH
14-BIT DATA LATCH
SCLK
DIN
SCLK
DIN
CONTROL
LOGIC
CONTROL
LOGIC
SERIAL INPUT REGISTER
SERIAL INPUT REGISTER
CLR
CLR
GND
GND
Chip Information
TRANSISTOR COUNT: 2800
PROCESS: BiCMOS
10 ______________________________________________________________________________________
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
________________________________________________________Package Information
______________________________________________________________________________________ 11
+3V/+5V, Serial-Input,
Voltage-Output, 14-Bit DACs
Package Information (continued)
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600_____________________12
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
相关型号：
MAX5143EUA+
D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO8, 3 X 5 MM, ROHS COMPLIANT, MINIATURE, MICRO MAX PACKAGE-8
MAXIM
MAX5143EUA+T
D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO8, 3 X 5 MM, MINIATURE, MICRO MAX PACKAGE-8
MAXIM
MAX5144EUB+T
D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO10, MICRO MAX PACKAGE-10
MAXIM
MAX5144EUB-T
D/A Converter, 1 Func, Serial Input Loading, 1us Settling Time, PDSO10, MICRO MAX PACKAGE-10
MAXIM
MAX514ACNG-T
D/A Converter, 4 Func, Serial Input Loading, 0.25us Settling Time, PDIP24, PLASTIC, DIP-24
MAXIM
©2020 ICPDF网 联系我们和版权申明