19-1428; Rev 0; 2/99
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
with Internal Reference
General Description
The MAX5120/MAX5121 are low-power, 12-bit, voltage-
output digital-to-analog converters (DACs) with an inter-
nal precision bandgap reference and an output amplifier.
The MAX5120 operates on a +5V supply with an internal
amplifier reference of +2.5V and is capable of a +4.095V
full-scale output range. The MAX5121, operating on +3V,
delivers its +2.0475V full-scale output with an internal
precision reference of +1.25V. If necessary, the user can
override the internal, <10ppm/°C voltage reference with
an external reference. Both devices draw only 500µA of
supply current, which reduces to 3µA in power-down
mode. In addition, their power-up reset feature allows for
a user-selectable initial output state of either 0V or mid-
scale and minimizes output voltage glitches during
power-up.
The serial interface is compatible with SPI™, QSPI™
and MICROWIRE™, which makes the MAX5120/
MAX5121 suitable for cascading multiple devices. Each
DAC has a double-buffered input organized as an input
register followed by a DAC register. A 16-bit shift regis-
ter loads data into the input register. The DAC register
may be updated independently or simultaneously with
the input register.
Both devices are available in a 16-pin QSOP package
and are specified for the extended industrial (-40°C to
+85°C) temperature range. For pin-compatible 14-bit
upgrades, see the MAX5170/MAX5172 data sheet;
for pin-compatible 13-bit versions, see the MAX5130/
MAX5131 data sheet.
o
Single-Supply Operation
+5V (MAX5120)
+3V (MAX5121)
o
Full-Scale Output Range
+4.095V (MAX5120)
+2.0475V (MAX5121)
o
Built-In 10ppm/°C (max) Precision Bandgap
Reference
+2.5V (MAX5120)
+1.25V (MAX5121)
o
Adjustable Output Offset
o
SPI/QSPI/MICROWIRE-Compatible, 3-Wire Serial
Interface
o
Pin-Programmable Shutdown Mode and Power-
Up Reset (0V or Midscale Output Voltage)
o
Buffered Output Capable of Driving 5kΩ
100pF
or 4–20mA Loads
o
Space-Saving 16-Pin QSOP Package
o
Pin-Compatible 13-Bit Upgrades Available
(MAX5130/MAX5131)
o
Pin-Compatible 14-Bit Upgrades Available
(MAX5170/MAX5172)
Features
MAX5120/MAX5121
________________________Applications
Industrial Process Controls
Automatic Test Equipment (ATE)
Digital Offset and Gain Adjustment
Motion Control
µP-Controlled Systems
Pin Configuration
TOP VIEW
OS 1
OUT 2
RSTVAL 3
PDL 4
CLR 5
CS 6
DIN 7
SCLK 8
16 V
DD
15 REFADJ
14 REF
Ordering Information
PART
MAX5120AEEE
MAX5120BEEE
MAX5121AEEE
MAX5121BEEE
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
16 QSOP
16 QSOP
16 QSOP
16 QSOP
INL
(LSB)
±0.5
±1
±1
±2
MAX5120
MAX5121
13 AGND
12 PD
11 UPO
10 DOUT
9
DGND
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
1
QSOP
________________________________________________________________
Maxim Integrated Products
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
with Internal Reference
MAX5120/MAX5121
ABSOLUTE MAXIMUM RATINGS
V
DD
to AGND, DGND ...............................................-0.3V to +6V
AGND to DGND.....................................................-0.3V to +0.3V
Digital Inputs to DGND.............................................-0.3V to +6V
Digital Outputs (DOUT, UPO) to DGND .....-0.3V to (V
DD
+ 0.3V)
OUT to AGND.............................................-0.3V to (V
DD
+ 0.3V)
OS to AGND ...................................(AGND - 4V) to (V
DD
+ 0.3V)
REF, REFADJ to AGND ..............................-0.3V to (V
DD
+ 0.3V)
Maximum Current into Any Pin............................................50mA
Continuous Power Dissipation (T
A
= +70°C)
QSOP (derate 8.00mW/°C above +70°C) .....................667mW
Operating Temperature Range ..........................-40°C to +85°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—MAX5120 (+5V)
(V
DD
= +5V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
STATIC PERFORMANCE
Resolution
Integral Nonlinearity (Note 1)
Differential Nonlinearity
Offset Error (Note 2)
Gain Error
Full-Scale Voltage
Full-Scale Temperature
Coefficient (Note 3)
Power-Supply Rejection Ratio
REFERENCE
Output Voltage
Output Voltage Temperature
Coefficient
Reference External Load Regulation
Reference Short-Circuit Current
REFADJ Current
DIGITAL INPUT
Input High Voltage
Input Low Voltage
Input Hysteresis
Input Leakage Current
Input Capacitance
DIGITAL OUTPUTS
Output High Voltage
Output Low Voltage
V
OH
V
OL
I
SOURCE
= 2mA
I
SINK
= 2mA
V
DD
- 0.5
0.13
0.4
V
V
V
IH
V
IL
V
HYS
I
IN
C
IN
V
IN
= 0 or V
DD
-1
200
0.001
8
1
3
0.8
V
V
mV
µA
pF
REFADJ = V
DD
V
REF
TCV
REF
V
OUT
/I
OUT
T
A
= +25°C
MAX5120A
MAX5120B
0
≤
I
OUT
≤
100µA (sourcing)
2.5
3
10
0.1
4
3.3
7
1
V
ppm/°C
µV/µA
mA
µA
N
INL
DNL
V
OS
GE
V
FS
TCV
FS
PSRR
Code = FFF hex, T
A
= +25°C
MAX5120A
MAX5120B
4.5V
≤
V
DD
≤
5.5V
MAX5120A
MAX5120B
12
-0.5
-1
-1
-10
-3
4.0458
-0.2
4.095
3
10
20
0.5
1
1
10
3
4.1442
10
30
250
Bits
LSB
LSB
mV
mV
V
ppm/°C
µV/V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
with Internal Reference
ELECTRICAL CHARACTERISTICS—MAX5120 (+5V) (continued)
(V
DD
= +5V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
DYNAMIC PERFORMANCE
Voltage Output Slew Rate
Output Settling Time
Output Voltage Swing (Note 4)
OS Input Resistance
Time Required to Exit Shutdown
Digital Feedthrough
POWER REQUIREMENTS
Power-Supply Voltage (Note 5)
Power-Supply Current (Note 5)
Power-Supply Current in Shutdown
V
DD
I
DD
I
SHDN
4.5
500
3
5.5
600
20
V
µA
µA
CS
= V
DD
, f
SCLK
= 100kHz,
V
SCLK
= 5Vp-p
R
OS
83
SR
To ±0.5LSB, V
STEP
= 4V
0.6
20
0 to V
DD
121
2
5
V/µs
µs
V
kΩ
ms
nV-s
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX5120/MAX5121
ELECTRICAL CHARACTERISTICS—MAX5121 (+3V)
(V
DD
= +3V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
STATIC PERFORMANCE
Resolution
Integral Nonlinearity (Note 1)
Differential Nonlinearity
Offset Error (Note 2)
Gain Error
Full-Scale Voltage
Full-Scale Temperature
Coefficient (Note 3)
Power-Supply Rejection Ratio
REFERENCE
Output Voltage
Output Voltage Temperature
Coefficient
Reference External Load Regulation
Reference Short-Circuit Current
REFADJ Current
DIGITAL INPUT
Input High Voltage
Input Low Voltage
Input Hysteresis
V
IH
V
IL
V
HYS
200
2.2
0.8
V
V
mV
REFADJ = V
DD
V
REF
TCV
REF
V
OUT
/I
OUT
T
A
= +25°C
MAX5121A
MAX5121B
0
≤
I
OUT
≤
100µA (sourcing)
1.25
3
10
0.1
4
3.3
7
1
V
ppm/°C
µV/µA
mA
µA
N
INL
DNL
V
OS
GE
V
FS
TCV
FS
PSRR
Data = FFF hex, T
A
= +25°C
MAX5121A
MAX5121B
2.7V
≤
V
DD
≤
3.3V
MAX5121A
MAX5121B
12
-1
-2
-1
-10
-5
2.0229
-0.2
2.0475
3
10
20
1
2
1
10
5
2.0721
10
30
250
Bits
LSB
LSB
mV
mV
V
ppm/°C
µV/V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
_______________________________________________________________________________________
3
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
with Internal Reference
MAX5120/MAX5121
ELECTRICAL CHARACTERISTICS—MAX5121 (+3V) (continued)
(V
DD
= +3V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
Input Leakage Current
Input Capacitance
DIGITAL OUTPUTS
Output High Voltage
Output Low Voltage
DYNAMIC PERFORMANCE
Voltage Output Slew Rate
Output Settling Time
Output Voltage Swing (Note 4)
OS Input Resistance
Time Required to Exit Shutdown
Digital Feedthrough
POWER REQUIREMENTS
Power-Supply Voltage (Note 5)
Power-Supply Current (Note 5)
Power-Supply Current in Shutdown
V
DD
I
DD
I
SHDN
2.7
500
3
3.6
600
20
V
µA
µA
CS
= V
DD
, f
SCLK
= 100kHz,
V
SCLK
= 3Vp-p
R
OS
83
SR
To ±0.5LSB, V
STEP
= 2V
0.6
20
0 to V
DD
121
2
5
V/µs
µs
V
kΩ
ms
nV-s
V
OH
V
OL
I
SOURCE
= 2mA
I
SINK
= 2mA
V
DD
- 0.5
0.13
0.4
V
V
SYMBOL
I
IN
C
IN
CONDITIONS
V
IN
= 0 or V
DD
MIN
-1
TYP
0.001
8
MAX
1
UNITS
µA
pF
TIMING CHARACTERISTICS—MAX5120 (+5V)
(V
DD
= +5V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SCLK Clock Period
SCLK Pulse Width High
SCLK Pulse Width Low
CS
Fall to SCLK Rise Setup Time
SCLK Rise to
CS
Rise Hold Time
SDI Setup Time
SDI Hold Time
SCLK Rise to DOUT Valid
Propagation Delay Time
SCLK Fall to DOUT Valid
Propagation Delay Time
SCLK Rise to
CS
Fall Delay Time
CS
Rise to SCLK Rise Hold Time
CS
Pulse Width High
SYMBOL
t
CP
t
CH
t
CL
t
CSS
t
CSH
t
DS
t
DH
t
DO1
t
DO2
t
CS0
t
CS1
t
CSW
C
LOAD
= 200pF
C
LOAD
= 200pF
10
40
100
CONDITIONS
MIN
100
40
40
40
0
40
0
80
80
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
4
_______________________________________________________________________________________
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
with Internal Reference
TIMING CHARACTERISTICS—MAX5121 (+3V)
(V
DD
= +3V ±10%, OS = AGND = DGND = 0V, 33nF capacitor at REFADJ, internal reference, R
L
= 5kΩ, C
L
= 100pF, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SCLK Clock Period
SCLK Pulse Width High
SCLK Pulse Width Low
CS
Fall to SCLK Rise Setup Time
SCLK Rise to
CS
Rise Hold Time
SDI Setup Time
SDI Hold Time
SCLK Rise to DOUT Valid
Propagation Delay Time
SCLK Fall to DOUT Valid
Propagation Delay Time
SCLK Rise to
CS
Fall Delay Time
CS
Rise to SCLK Rise Hold Time
CS
Pulse Width High
SYMBOL
t
CP
t
CH
t
CL
t
CSS
t
CSH
t
DS
t
DH
t
DO1
t
DO2
t
CS0
t
CS1
t
CSW
C
LOAD
= 200pF
C
LOAD
= 200pF
10
75
150
CONDITIONS
MIN
150
75
75
60
0
60
0
200
200
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
MAX5120/MAX5121
Note 1:
Accuracy is guaranteed as shown in the following table:
V
DD
(V)
5
3
Accuracy Guaranteed
From Code:
10
20
To Code:
4095
4095
Note 2:
Offset is measured at the code closest to 10mV.
Note 3:
The temperature coefficient is determined by the “box” method in which the maximum
∆V
OUT
over the temperature range is
divided by
∆T.
Note 4:
Accuracy is better than 1.0LSB for V
OUT
= 10mV to (V
DD
- 180mV). Guaranteed by PSR test on end points.
Note 5:
R
LOAD
=
∞
and digital inputs are at either V
DD
or DGND.
Typical Operating Characteristics
(V
DD
= +5V (MAX5120), V
DD
= +3V (MAX5121), R
L
= 5kΩ, C
L
= 100pF, OS = AGND, T
A
= +25°C, unless otherwise noted.)
MAX5120
INTEGRAL NONLINEARITY vs.
DIGITAL INPUT CODE
MAX5120/21 toc01
MAX5120
DIFFERENTIAL NONLINEARITY vs.
DIGITAL INPUT CODE
0.15
0.10
DNL (LSB)
0.05
0
MAX5120/21 toc02
MAX5120
REFERENCE VOLTAGE vs. TEMPERATURE
MAX5120/21 toc03
0.20
0.15
0.10
INL (LSB)
0.05
0
0.20
2.510
REFERENCE VOLTAGE (V)
2.505
2.500
-0.05
-0.10
-0.15
-0.20
0
1000
2000
3000
4000
5000
DIGITAL INPUT CODE
-0.05
-0.10
-0.15
-0.20
0
1000
2000
3000
4000
5000
DIGITAL INPUT CODE
2.495
2.490
-60 -40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
_______________________________________________________________________________________
5