19-1167; Rev 1; 2/97
10-Bit Voltage-Output DACs
in 8-Pin µMAX
______________________________Features
♦ 10-Bit DAC with Configurable Output Amplifier
The output amplifier’s inverting input is available to the
user, allowing specific gain configurations, remote
sensing, and high output current capability. This makes
the MAX5354/MAX5355 ideal for a wide range of applications, including industrial process control. Other features include a software shutdown and power-on reset.
The serial interface is compatible with SPI™/QSPI™
and Microwire™. The DAC has a double-buffered input,
organized as an input register followed by a DAC register. A 16-bit serial word loads data into the input register. The DAC register can be updated independently or
simultaneously with the input register. All logic inputs
are TTL/CMOS-logic compatible and buffered with
Schmitt triggers to allow direct interfacing to optocouplers.
♦ Available in 8-Pin µMAX
________________________Applications
Digital Offset and Gain Adjustment
Industrial Process Controls
♦ +5V Single-Supply Operation (MAX5354)
+3.3V Single-Supply Operation (MAX5355)
♦ Low Supply Current: 0.28mA Normal Operation
2µA Shutdown Mode
♦ Power-On Reset Clears DAC Output to Zero
♦ SPI/QSPI and Microwire Compatible
♦ Schmitt-Trigger Digital Inputs for Direct
Optocoupler Interface
♦ +3.3V MAX5355 Directly Interfaces with +5V Logic
_________________Ordering Information
PART*
TEMP. RANGE
PIN-PACKAGE
MAX5354CPA
0°C to +70°C
8 Plastic DIP
MAX5354CUA
0°C to +70°C
8 µMAX
MAX5354EPA
-40°C to +85°C
8 Plastic DIP
MAX5354EUA
-40°C to +85°C
8 µMAX
MAX5354MJA
-55°C to +125°C
8 CERDIP**
Ordering Information continued at end of data sheet.
*Contact factory for availability of 8-pin SO package.
**Contact factory for availability and processing to MIL-STD-883.
Microprocessor-Controlled Systems
Portable Test Instruments
Remote Industrial Controls
____________________Functional Diagram
VDD
GND
REF
FB
DAC
REGISTER
_______________________Pin Configuration
TOP VIEW
OUT
DAC
OUT 1
8
VDD
7
GND
6
REF
5
FB
CONTROL
CS 2
INPUT
REGISTER
DIN 3
CS
DIN
SCLK
16-BIT
SHIFT
REGISTER
MAX5354
MAX5355
MAX5354
MAX5355
SCLK 4
DIP/µMAX
SPI and QSPI are trademarks of Motorola, Inc. Microwire is a trademark of National Semiconductor Corp.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
MAX5354/MAX5355
__________________General Description
The MAX5354/MAX5355 combine a low-power, voltageoutput, 10-bit digital-to-analog converter (DAC) and a
precision output amplifier in an 8-pin µMAX or DIP package. The MAX5354 operates from a single +5V supply,
and the MAX5355 operates from a single +3.3V supply.
Both devices draw less than 280µA of supply current.
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
ABSOLUTE MAXIMUM RATINGS
VDD to GND ..............................................................-0.3V to +6V
REF, OUT, FB to GND ................................-0.3V to (VDD + 0.3V)
Digital Inputs to GND ...............................................-0.3V to +6V
Continuous Current into Any Pin.......................................±20mA
Continuous Power Dissipation (TA = +70°C)
Plastic DIP (derate 9.09mW/°C above +70°C) .................727mW
µMAX (derate 4.10mW/°C above +70°C) ......................330mW
CERDIP (derate 8.00mW/°C above +70°C) ...................640mW
Operating Temperature Ranges
MAX5354C_A/MAX5355C_A ................................0°C to +70°C
MAX5354E_A/MAX5355E_A ..............................-40°C to +85°C
MAX5354MJA/MAX5355MJA ..........................-55°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
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: MAX5354
(VDD = +5V ±10%, GND = 0V, REF = 2.5V, RL = 5kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C. Output buffer connected in unity-gain configuration (Figure 8).)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
STATIC PERFORMANCE—ANALOG SECTION
Resolution
N
10
Bits
MAX5354C/E
±1
MAX5354M
±2
Integral Nonlinearity
(Note 1)
INL
Differential Nonlinearity
DNL
Offset Error
VOS
±0.3
TCVOS
6
GE
-0.3
Offset-Error Tempco
Gain Error (Note 1)
Guaranteed monotonic
±1.0
Gain-Error Tempco
Power-Supply Rejection Ratio
±8
4.5V ≤ VDD ≤ 5.5V
LSB
mV
ppm/°C
±2
1
PSRR
LSB
LSB
ppm/°C
800
µV/V
REFERENCE INPUT
Reference Input Range
VREF
Reference Input Resistance
RREF
0
Code dependent, minimum at code 1550 hex
18
VDD - 1.4
V
30
kΩ
MULTIPLYING-MODE PERFORMANCE
Reference -3dB Bandwidth
VREF = 0.67Vp-p
650
kHz
Reference Feedthrough
Input code = all 0s, VREF = 3.6Vp-p at 1kHz
-84
dB
VREF = 1Vp-p at 25kHz, code = full scale
77
dB
Signal-to-Noise Plus
Distortion Ratio
SINAD
DIGITAL INPUTS
2
Input High Voltage
VIH
Input Low Voltage
VIL
Input Leakage Current
IIN
Input Capacitance
CIN
2.4
VIN = 0V or VDD
V
0.001
8
_______________________________________________________________________________________
0.8
V
±0.5
µA
pF
10-Bit Voltage-Output DACs
in 8-Pin µMAX
(VDD = +5V ±10%, GND = 0V, REF = 2.5V, RL = 5kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C. Output buffer connected in unity-gain configuration (Figure 8).)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DIGITAL INPUTS
DYNAMIC
PERFORMANCE
Voltage Output Slew Rate
SR
Output Settling Time
To ±1/2LSB, VSTEP = 2.5V
Output Voltage Swing
Rail-to-rail (Note 2)
0.6
V/µs
10
µs
0 to VDD
V
Current into FB
0.001
Start-Up Time
20
µs
5
nV-s
CS = VDD, DIN = 100kHz
Digital Feedthrough
±0.1
µA
POWER SUPPLIES
Supply Voltage
VDD
Supply Current
IDD
Supply Current in Shutdown
4.5
(Note 3)
5.5
V
0.4
mA
4
20
µA
0.001
±0.5
µA
0.28
(Note 3)
Reference Current in Shutdown
TIMING CHARACTERISTICS (Figure 6)
SCLK Clock Period
tCP
100
ns
SCLK Pulse Width High
tCH
40
ns
SCLK Pulse Width Low
tCL
40
ns
CS Fall to SCLK Rise Setup Time
tCSS
40
ns
SCLK Rise to CS Rise Hold Time
tCSH
0
ns
tDS
40
ns
DIN Setup Time
DIN Hold Time
tDH
0
ns
SCLK Rise to CS Fall Delay
tCS0
40
ns
CS Rise to SCLK Rise Hold Time
tCS1
40
ns
CS Pulse Width High
tCSW
100
ns
Note 1: Guaranteed from code 3 to code 1023 in unity-gain configuration.
Note 2: Accuracy is better than 1LSB for VOUT = 8mV to VDD - 100mV, guaranteed by a power-supply rejection test at the
end points.
Note 3: RL = ∞, digital inputs at GND or VDD.
_______________________________________________________________________________________
3
MAX5354/MAX5355
ELECTRICAL CHARACTERISTICS: MAX5354 (continued)
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
ELECTRICAL CHARACTERISTICS: MAX5355
(VDD = +3.15V to +3.6V, REF = 1.25V, GND = 0V, RL = 5kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted. Typical values
are at TA = +25°C. Output buffer connected in unity-gain configuration (Figure 8).)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
STATIC PERFORMANCE—ANALOG SECTION
Resolution
N
Integral Nonlinearity
(Note 4)
INL
Differential Nonlinearity
DNL
Offset Error
VOS
Offset-Error Tempco
Gain Error (Note 4)
10
±1
MAX5355M
±2
Guaranteed monotonic
±0.3
TCVOS
6
GE
-0.3
Gain-Error Tempco
Power-Supply Rejection Ratio
Bits
MAX5355C/E
LSB
±1.0
LSB
±8
mV
ppm/°C
±2
1
LSB
ppm/°C
PSRR
800
µV/V
REFERENCE INPUT
Reference Input Range
VREF
Reference Input Resistance
RREF
0
Code dependent, minimum at code 1550 hex
18
VDD - 1.4
V
30
kΩ
MULTIPLYING-MODE PERFORMANCE (VDD = +3.3V)
Reference -3dB Bandwidth
VREF = 0.67Vp-p
650
kHz
Reference Feedthrough
Input code = all 0s, VREF = 1.9Vp-p at 1kHz
-84
dB
VREF = 1Vp-p at 25kHz, code = full scale
72
dB
Signal-to-Noise Plus
Distortion Ratio
SINAD
DIGITAL INPUTS
Input High Voltage
VIH
Input Low Voltage
VIL
2.4
Input Leakage Current
IIN
Input Capacitance
CIN
8
pF
SR
0.6
V/µs
10
µs
VIN = 0V or VDD
V
0.001
0.6
V
±0.5
µA
DYNAMIC PERFORMANCE
Voltage Output Slew Rate
Output Settling Time
To ±1/2LSB, VSTEP = 1.25V
Output Voltage Swing
Rail-to-rail (Note 5)
0 to VDD
Current into FB
0.001
Start-Up Time
CS = VDD, DIN = 100kHz
Digital Feedthrough
V
±0.1
µA
20
µs
5
nV-s
POWER SUPPLIES
Supply Voltage
VDD
Supply Current
IDD
Supply Current in Shutdown
Reference Current in Shutdown
4
3.15
(Note 6)
(Note 6)
3.6
V
0.4
mA
1.6
10
µA
0.001
±0.5
µA
0.24
_______________________________________________________________________________________
10-Bit Voltage-Output DACs
in 8-Pin µMAX
(VDD = +3.15V to +3.6V, REF = 1.25V, GND = 0V, RL = 5kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted. Typical values
are at TA = +25°C. Output buffer connected in unity-gain configuration (Figure 8).)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
TIMING CHARACTERISTICS (Figure 6)
SCLK Clock Period
tCP
100
ns
SCLK Pulse Width High
tCH
40
ns
SCLK Pulse Width Low
tCL
40
ns
CS Fall to SCLK Rise Setup Time
tCSS
40
ns
SCLK Rise to CS Rise Hold Time
tCSH
0
ns
DIN Setup Time
tDS
40
ns
DIN Hold Time
tDH
0
ns
SCLK Rise to CS Fall Delay
tCS0
40
ns
CS Rise to SCLK Rise Hold Time
tCS1
40
ns
CS Pulse Width High
tCSW
100
ns
Note 4: Guaranteed from code 6 to code 1023 in unity-gain configuration.
Note 5: Accuracy is better than 1LSB for VOUT = 8mV to VDD - 150mV, guaranteed by a power-supply rejection test at the
end points.
Note 6: RL = ∞, digital inputs at GND or VDD.
_______________________________________________________________________________________
5
MAX5354/MAX5355
ELECTRICAL CHARACTERISTICS: MAX5355 (continued)
__________________________________________Typical Operating Characteristics
(MAX5354 only, VDD = +5V, RL = 5kΩ, CL = 100pF, TA = +25°C, unless otherwise noted.)
MAX5354
REFERENCE VOLTAGE INPUT
FREQUENCY RESPONSE
-0.025
360
SUPPLY CURRENT (µA)
RELATIVE OUTPUT (dB)
0
RL = ∞
380
-4
0.025
INL (LSB)
400
MAX5354-02
0
MAX5354-01
0.050
SUPPLY CURRENT
vs. TEMPERATURE
MAX5354-03
INTEGRAL NONLINEARITY
vs. REFERENCE VOLTAGE
-8
-12
-16
340
320
300
280
260
240
220
-20
1.2
2.0
2.8
3.6
0
4.4
500k
1M
REFERENCE VOLTAGE (V)
20
60
100
140
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
-50
MAX5354-05
9
450
VREF = 2.5VDC + 1 Vp-p SINE
CODE = FULL SCALE
-55
400
7
6
5
4
3
-60
350
THD + NOISE (dB)
SUPPLY CURRENT (µA)
8
300
250
200
100
1
50
20
60
100
-90
4.4
4.8
5.6
FREQUENCY (kHz)
REFERENCE FEEDTHROUGH
AT 1kHz
2.49976
-60
-80
2.49972
2.49968
2.49964
1.6
2.7
3.8
FREQUENCY (kHz)
4.9
6.0
2.49956
0.1k
-40
-60
OUTPUT FEEDTHROUGH
-80
2.49960
-100
REFERENCE INPUT SIGNAL
-20
SIGNAL AMPLITUDE (dB)
OUTPUT VOLTAGE (V)
-40
0
MAX5354-08
2.49980
MAX5354-07
VREF = +3.6Vp-p
CODE = FULL SCALE
fIN = 1kHz
100
10
1
6.0
OUTPUT VOLTAGE
vs. LOAD
OUTPUT FFT PLOT
-20
5.2
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
0
-75
-85
4.0
140
-70
-80
0
-20
-65
150
2
0.5
-20
TEMPERATURE (°C)
500
MAX5354-04
POWER-DOWN SUPPLY CURRENT (µA)
200
-60
3M
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
10
6
2.5M
FREQUENCY (Hz)
POWER-DOWN SUPPLY CURRENT
vs. TEMPERATURE
0
-60
2M
1.5M
MAX5354-09a/09b
0.4
MAX5354-06
-0.050
SIGNAL AMPLITUDE (dB)
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
-100
1k
10k
LOAD (Ω)
100k
1M
0.5
1.6
2.7
3.8
FREQUENCY (kHz)
_______________________________________________________________________________________
4.9
6.0
10-Bit Voltage-Output DACs
in 8-Pin µMAX
(MAX5354 only, VDD = +5V, RL = 5kΩ, CL = 100pF, TA = +25°C, unless otherwise noted.)
MAX5354 (continued)
DIGITAL FEEDTHROUGH (fSCLK = 100kHz)
MAX5354-11a
MAX5354-10a
MAJOR-CARRY TRANSITION
CS
5V/div
SCLK,
2V/div
OUT,
AC COUPLED
100mV/div
OUT,
AC COUPLED
10mV/div
CODE = 512
2µs/div
10µs/div
CS = 5V
MAX5354-12a
DYNAMIC RESPONSE
OUT
1V/div
GND
10µs/div
GAIN = +2, SWITCHING FROM CODE 0 TO 1005
_______________________________________________________________________________________
7
MAX5354/MAX5355
____________________________Typical Operating Characteristics (continued)
____________________________Typical Operating Characteristics (continued)
(MAX5355 only, VDD = +3.3V, RL = 5kΩ, CL = 100pF, TA = +25°C, unless otherwise noted.)
MAX5355
-0.025
SUPPLY CURRENT (µA)
RELATIVE OUTPUT (dB)
0
-8
-12
MAX5355-12
RL = ∞
340
-4
0.025
INL (LSB)
360
MAX5355-11
0
MAX5355-10
0.050
SUPPLY CURRENT
vs. TEMPERATURE
REFERENCE VOLTAGE INPUT
FREQUENCY RESPONSE
INTEGRAL NONLINEARITY
vs. REFERENCE VOLTAGE
-16
320
300
280
260
240
220
0.8
1.2
1.6
2.0
REFERENCE VOLTAGE (V)
2.4
500k
2.5M
2.0
1.5
350
THD + NOISE (dB)
SUPPLY CURRENT (µA)
2.5
300
250
200
1.0
100
-20
20
60
100
3.1
3.2
TEMPERATURE (°C)
OUTPUT FFT PLOT
3.4
3.5
3.6
-60
-80
0.5
1.6
2.7
3.8
FREQUENCY (kHz)
4.9
6.0
-70
3.8
FULL-SCALE OUTPUT
vs. LOAD
REFERENCE FEEDTHROUGH
AT 1kHz
0
MAX5355-17
1.24930
1.24925
1.24920
1.24910
100
100
10
1
FREQUENCY (kHz)
REFERENCE INPUT SIGNAL
-20
-40
-60
OUTPUT FEEDTHROUGH
-80
1.24915
-100
-65
SUPPLY VOLTAGE (V)
1.24935
-40
3.7
SIGNAL AMPLITUDE (dB)
-20
3.3
1.24940
MAX5355-16
VREF = 1.9Vp-p
CODE = FULL SCALE
fIN = 1kHz
FULL-SCALE OUTPUT (V)
0
-60
-80
3.0
140
140
-75
150
0.5
100
VREF = 1VDC + 0.5Vp-p SINE
CODE = FULL SCALE
-55
4.0
3.0
60
-50
MAX5355-14
400
3.5
20
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
450
MAX5355-13
4.5
0
-60
-20
TEMPERATURE (°C)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
5.0
POWER-DOWN SUPPLY CURRENT (µA)
2M
1.5M
FREQUENCY (Hz)
POWER-DOWN SUPPLY CURRENT
vs. TEMPERATURE
8
1M
200
-60
MAX5355-15
0.4
-20
100k
MAX5355-18
-0.050
SIGNAL AMPLITUDE (dB)
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
-100
1k
10k
100k
LOAD (Ω)
1M
10M
0.5
1.2
1.9
2.6
FREQUENCY (kHz)
_______________________________________________________________________________________
3.3
4.0
10-Bit Voltage-Output DACs
in 8-Pin µMAX
FB
PIN
NAME
FUNCTION
1
OUT
2
CS
Chip-Select Input. Active low.
3
DIN
Serial-Data Input
4
SCLK
Serial-Clock Input
5
FB
6
REF
Reference Voltage Input
7
GND
Ground
8
VDD
Positive Power Supply
R
DAC Output Voltage
DAC Output Amplifier Feedback
2R
2R
R
2R
OUT
R
2R
2R
MSB
REF
AGND
SHOWN FOR ALL 1s ON DAC
Figure 1. Simplified DAC Circuit Diagram
_______________Detailed Description
The MAX5354/MAX5355 contain a voltage-output digital-to-analog converter (DAC) that is easily addressed
using a simple 3-wire serial interface. Each IC includes
a 16-bit shift register, and has a double-buffered input
composed of an input register and a DAC register (see
Functional Diagram). In addition to the voltage output,
the amplifier’s negative input is available to the user.
The DAC is an inverted R-2R ladder network that converts a digital input (10 data bits plus three sub-bits)
into an equivalent analog output voltage in proportion
to the applied reference voltage. Figure 1 shows a simplified circuit diagram of the DAC.
Reference Inputs
The reference input accepts positive DC and AC signals. The voltage at the reference input sets the fullscale output voltage for the DAC. The reference input
voltage range is 0V to (VDD - 1.4V). The output voltage
(VOUT) is represented by a digitally programmable voltage source, as expressed in the following equation:
VOUT = (VREF x NB / 1024) x Gain
where NB is the numeric value of the DAC’s binary
input code (0 to 1023), VREF is the reference voltage,
and Gain is the externally set voltage gain.
The impedance at the reference input is code dependent, ranging from a low value of 18kΩ when the DAC
has an input code of 1550 hex, to a high value exceeding several giga ohms (leakage currents) with an input
code of 0000 hex. Because the input impedance at the
reference pin is code dependent, load regulation of the
reference source is important.
In shutdown mode, the MAX5354/MAX5355’s REF input
enters a high-impedance state with a typical input leakage current of 0.001µA.
The reference input capacitance is also code dependent and typically ranges from 15pF (with an input
code of all 0s) to 50pF (at full scale).
The MAX873 +2.5V reference is recommended for use
with the MAX5354.
Output Amplifier
The MAX5354/MAX5355’s DAC output is internally
buffered by a precision amplifier with a typical slew rate
of 0.6V/µs. Access to the output amplifier’s inverting
input provides the user greater flexibility in output gain
setting/signal conditioning (see the Applications
Information section).
With a full-scale transition at the MAX5354/MAX5355
output, the typical settling time to ±1/2LSB is 10µs
when loaded with 5kΩ in parallel with 100pF (loads less
than 2kΩ degrade performance).
The amplifier’s output dynamic responses and settling
performances are shown in the Typical Operating
Characteristics.
Shutdown Mode
The MAX5354/MAX5355 feature a software-programmable shutdown that reduces supply current to a typical
value of 4µA. Writing 111X XXXX XXXX XXXX as the inputcontrol word puts the device in shutdown mode (Table 1).
_______________________________________________________________________________________
9
MAX5354/MAX5355
_____________________Pin Description
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
In shutdown mode, the amplifier’s output and the reference input enter a high-impedance state. The serial
interface remains active. Data in the input register is
retained in shutdown, allowing the MAX5354/MAX5355
to recall the output state prior to entering shutdown. Exit
shutdown mode by either recalling the previous configuration or updating the DAC with new data. When powering up the device or bringing it out of shutdown, allow
20µs for the outputs to stabilize.
MAX5354
MAX5355
SCLK
SK
DIN
SO
CS
I/O
MICROWIRE
PORT
Serial-Interface Configurations
The MAX5354/MAX5355’s 3-wire serial interface is compatible with both Microwire™ (Figure 2) and
SPI™/QSPI™ (Figure 3). The serial input word consists of
three control bits followed by 10+3 data bits (MSB first),
as shown in Figure 4. The 3-bit control code determines
the MAX5354/MAX5355’s response outlined in Table 1.
The MAX5354/MAX5355’s digital inputs are double
buffered. Depending on the command issued through
the serial interface, the input register can be loaded
without affecting the DAC register, the DAC register can
be loaded directly, or the DAC register can be updated
from the input register (Table 1).
The +3.3V MAX5355 can also directly interface with +5V
logic.
Figure 2. Connections for Microwire
+5V
SS
Serial-Interface Description
The MAX5354/MAX5355 require 16 bits of serial data.
Table 1 lists the serial-interface programming commands. For certain commands, the 10+3 data bits are
“don’t cares.” Data is sent MSB first and can be sent in
two 8-bit packets or one 16-bit word (CS must remain
low until 16 bits are transferred). The serial data is composed of three control bits (C2, C1, C0), followed by the
10+3 data bits D9...D0, S2, S1, S0 (Figure 4). Set the
sub-bits (S2, S1, S0) to zero. The 3-bit control code
determines:
• the register to be updated,
• the configuration when exiting shutdown.
Figure 5 shows the serial-interface timing requirements.
The chip-select pin (CS) must be low to enable the
DAC’s serial interface. When CS is high, the interface
control circuitry is disabled. CS must go low at least
t CSS before the rising serial clock (SCLK) edge to
properly clock in the first bit. When CS is low, data is
clocked into the internal shift register via the serial-data
input pin (DIN) on SCLK’s rising edge. The maximum
guaranteed clock frequency is 10MHz. Data is latched
into the MAX5354/MAX5355 input/DAC register on CS’s
rising edge.
DIN
MAX5354
MAX5355
MOSI
SCLK
SCK
CS
I/O
CPOL = 0, CPHA = 0
Figure 3. Connections for SPI/QSPI
MSB ..................................................................................LSB
16 Bits of Serial Data
Control
Bits
C2
C1
Data Bits
MSB............................LSB Sub-Bits
C0
D9 ...............................D0, S2, S1, S0
3 Control
Bits
10+3 Data Bits
Figure 4. Serial-Data Format
10
SPI/QSPI
PORT
______________________________________________________________________________________
10-Bit Voltage-Output DACs
in 8-Pin µMAX
MAX5354/MAX5355
Table 1. Serial-Interface Programming Commands
16-BIT16-BIT
SERIAL
SERIAL
WORDWORD
C2 C1
FUNCTION
C0
D9.......................D0
MSB
LSB
S2...S0
X
0
0
10 bits of data
000
Load input register; DAC register immediately updated (also exit
shutdown).
X
0
1
10 bits of data
000
Load input register; DAC register unchanged.
X
1
0
XXXXXXXXXX
XXX
Update DAC register from input register (also exit shutdown; recall
previous state).
1
1
1
XXXXXXXXXX
XXX
Shutdown
0
1
1
XXXXXXXXXX
XXX
No operation (NOP)
“X” = Don’t care
CS
COMMAND
EXECUTED
SCLK
1
DIN
8
C1
C2
C0
D9
D8
D7
D6
D5
9
D4
16
D3
D2
D1
D0
S2
S1
S0
Figure 5. Serial-Interface Timing Diagram
tCSW
CS
tCSO
tCSS
tCL
tCH
tCP
tCSH
tCS1
SCLK
tDS
tDH
DIN
Figure 6. Detailed Serial-Interface Timing Diagram
______________________________________________________________________________________
11
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
DIN
SCLK
CS1
CS2
TO OTHER
SERIAL DEVICES
CS3
CS
CS
MAX5354
MAX5355
CS
MAX5354
MAX5355
MAX5354
MAX5355
SCLK
SCLK
SCLK
DIN
DIN
DIN
Figure 7. Multiple MAX5354/MAX5355s Sharing Common DIN and SCLK Lines
Figure 7 shows a method of connecting several
MAX5354/MAX5355s. In this configuration, the clock
and the data bus are common to all devices, and separate chip-select lines are used for each IC.
__________Applications Information
Table 2. Unipolar Code Table
MSB
DAC CONTENTS
LSB
11 1111 1111
(000)
1023
+VREF
1024
10 0000 0001
(000)
513
+VREF
1024
10 0000 0000
(000)
512
+ VREF
+VREF
=
2
1024
01 1111 1111
(000)
511
+VREF
1024
00 0000 0001
(000)
1
+VREF
1024
00 0000 0000
(000)
Unipolar Output
For a unipolar output, the output voltage and the reference input have the same polarity. Figure 8 shows the
MAX5354/MAX5355 unipolar output circuit, which is
also the typical operating circuit. Table 2 lists the unipolar output codes.
Figure 9 illustrates a rail-to-rail output configuration.
This circuit shows the MAX5354 with the output amplifier configured for a closed-loop gain of +2, to provide a
0V to 5V full-scale range when a 2.5V reference is
used. When the MAX5355 is used with a 1.25V reference, this circuit provides a 0V to 2.5V full-scale range.
ANALOG OUTPUT
0V
Bipolar Output
The MAX5354/MAX5355 output can be configured for
bipolar operation using Figure 10’s circuit, according to
the following equation:
VOUT = VREF [(2NB / 1024) - 1]
where NB is the numeric value of the DAC’s binary
input code. Table 3 shows digital codes (offset binary)
and corresponding output voltage for Figure 10’s circuit.
12
NOTE: ( ) are for sub-bits.
Using an AC Reference
In applications where the reference has AC-signal components, the MAX5354/MAX5355 have multiplying
capability within the reference input range specifications. Figure 11 shows a technique for applying a sinewave signal to the reference input where the AC signal
is offset before being applied to REF. The reference
voltage must never be more negative than GND.
______________________________________________________________________________________
10-Bit Voltage-Output DACs
in 8-Pin µMAX
MSB
DAC CONTENTS
LSB
ANALOG OUTPUT
11 1111 1111
(000)
511
+VREF
512
10 0000 0001
(000)
1
+VREF
512
10 0000 0000
(000)
01 1111 1111
(000)
1
-VREF
512
00 0000 0001
(000)
511
-VREF
512
00 0000 0000
(000)
The MAX5354’s total harmonic distortion plus noise
(THD+N) is typically less than -77dB (full-scale code),
and the MAX5355’s THD+N is typically less than -72dB
(full-scale code), given a 1Vp-p signal swing and input
frequencies up to 25kHz. The typical -3dB frequency is
650kHz for both devices, as shown in the Typical
Operating Characteristics graphs.
Digitally Programmable Current Source
0V
512
-VREF
= - VREF
512
The circuit of Figure 12 places an NPN transistor
(2N3904 or similar) within the op-amp feedback loop
to implement a digitally programmable, unidirectional
current source. The output current is calculated with
the following equation:
IOUT = (VREF/R) x (NB/1024)
where NB is the numeric value of the DAC’s binary
input code and R is the sense resistor shown in
Figure 12.
NOTE: ( ) are for sub-bits.
MAX5354
MAX5355
MAX5354
MAX5355
+5V/3.3V
REF
+5V/+3.3V
REF
VDD
VDD
FB
10k
FB
10k
DAC
OUT
GND
Figure 8. Unipolar Output Circuit
DAC
OUT
GND
Figure 9. Unipolar Rail-to-Rail Output Circuit
______________________________________________________________________________________
13
MAX5354/MAX5355
Table 3. Bipolar Code Table
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
R1
+5V/
+3.3V
R2
REF
AC
REFERENCE
INPUT
+5V/+3.3V
VDD
V+
+5V/+3.3V
26k
MAX495
500mVp-p
FB
10k
VDD
REF
VOUT
DAC
OUT
V-
MAX5354
MAX5355
GND
DAC
OUT
R1 = R2 = 10kΩ ± 0.1%
MAX5354
MAX5355 GND
Figure 10. Bipolar Output Circuit
Figure 11. AC Reference Input Circuit
Grounding and Layout Considerations
+5V/+3.3V REF
VDD
VL
DAC
MAX5354
MAX5355
IOUT
OUT
2N3904
Digital or AC transient signals on GND can create noise
at the analog output. Tie GND to the highest-quality
ground available.
Good printed circuit board ground layout minimizes
crosstalk between the DAC output, reference input, and
digital input. Reduce crosstalk by keeping analog lines
away from digital lines. Wire-wrapped boards are not
recommended.
FB
GND
R
Figure 12. Digitally Programmable Current Source
Power-Supply Considerations
On power-up, the input and DAC registers are cleared
(set to zero code).
For rated MAX5354/MAX5355 performance, REF must
be at least 1.4V below VDD. Bypass VDD with a 4.7µF
capacitor in parallel with a 0.1µF capacitor to GND.
Use short lead lengths and place the bypass capacitors as close to the supply pins as possible.
14
______________________________________________________________________________________
10-Bit Voltage-Output DACs
in 8-Pin µMAX
___________________Chip Information
PART*
MAX5355CPA
MAX5355CUA
MAX5355EPA
MAX5355EUA
MAX5355MJA
TRANSISTOR COUNT: 1677
TEMP. RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
PIN-PACKAGE
8 Plastic DIP
8 µMAX
8 Plastic DIP
8 µMAX
8 CERDIP**
MAX5354/MAX5355
_Ordering Information (continued)
*Contact factory for availability of 8-pin SO package.
**Contact factory for availability and processing to MIL-STD-883.
PDIPN.EPS
CDIPS.EPS
________________________________________________________Package Information
______________________________________________________________________________________
15
___________________________________________Package Information (continued)
8LUMAXD.EPS
MAX5354/MAX5355
10-Bit Voltage-Output DACs
in 8-Pin µMAX
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.
16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1997 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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