Rainbow Electronics MAX5302 User Manual

__________________General Description

The MAX5302 combines a low-power, voltage-output, 12-bit digital-to-analog converter (DAC) and a precision output amplifier in an 8-pin µMAX package. It operates from a single +5V supply, drawing less than 280µA of supply current.

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 MAX5302 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 SPI™/QSPI™/MICROWIRE™ compatible. 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/CMOSlogic compatible and buffered with Schmitt triggers to allow direct interfacing to optocouplers.

Applications

Industrial Process Control

Automatic Test Equipment

Digital Offset and Gain Adjustment

Motion Control

Remote Industrial Control

Microprocessor-Controlled Systems

Features

♦ 12-Bit DAC with Configurable Output Amplifier

♦ +5V Single-Supply Operation

♦ Low Supply Current: 0.28mA Normal Operation

2µA Shutdown Mode

♦ Available in 8-Pin µMAX

♦ Power-On Reset Clears DAC Output to Zero

♦ SPI/QSPI/MICROWIRE Compatible

♦ Schmitt-Trigger Digital Inputs for Direct

Optocoupler Interface

MAX5302

Low-Power, 12-Bit Voltage-Output DAC

with Serial Interface

________________________________________________________________ Maxim Integrated Products 1

MAX5302

OUT

DIN

SCLK

DAC

REF

DAC

INPUT

CONTROL

GND

16-BIT

SHIFT

Functional Diagram Pin Configuration

19-1559; Rev 0; 10/99

Ordering Information

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.

SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp.

8 µMAX

PIN-PACKAGETEMP. RANGE

0°C to +70°C

-40°C to +85°CMAX5302EUA

MAX5302CUA

PART

REF

DIN

SCLK

GND

OUT

MAX5302

µMAX

TOP VIEW

MAX5302

Low-Power, 12-Bit Voltage-Output DAC with Serial Interface

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 8, VDD= +5V ±10%, V

REF

= +2.5V, RL= 5kΩ, CL= 100pF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical val-

ues are at T

= +25°C. Output buffer connected in unity-gain configuration.)

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.

VDDto GND..............................................................-0.3V to +6V

REF, OUT, FB to GND ................................-0.3V to (V

+ 0.3V)

Digital Inputs to GND ...............................................-0.3V to +6V

Continuous Current into Any Pin.......................................±20mA

Continuous Power Dissipation (T

= +70°C)

8-Pin µMAX (derate 4.10mW/°C above +70°C) .........330mW

Operating Temperature Ranges

MAX5302CUA...................................................0°C to +70°C

MAX5302EUA ................................................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10sec) .............................+300°C

Code dependent, minimum at code 1554 hex

4.5V ≤ VDD≤ 5.5V

CONDITIONS

kΩ

14 20R

REF

Reference Input Resistance

- 1.4V

REF

Reference Input Range

µV/V

PSRR

Power-Supply Rejection Ratio

800

±4

Bits

12N

Resolution

ppm/°C1Gain-Error Tempco

LSBGEGain Error (Note 1) -0.3 ±3

ppm/°C6TCV

Offset-Error Tempco

LSBINLIntegral Nonlinearity (Note 1)

±0.3 ±8 mVV

Offset Error

UNITS

MIN TYP MAXSYMBOL

PARAMETER

REF

= 0.67Vp-p

kHz

650

Reference -3dB Bandwidth

Input code = all 0s, V

REF

= 3.6Vp-p at 1kHz

REF

= 1Vp-p at 25kHz, code = full scale

77SINAD

Signal-to-Noise Plus Distortion Ratio

dB-84Reference Feedthrough

2.4V

Input Voltage High

VIN= 0 or V

pF8C

Input Capacitance

µA0.001 ±0.5I

Input Leakage Current

V0.8V

Input Voltage Low

STATIC PERFORMANCE—ANALOG SECTION

DIGITAL INPUTS

REFERENCE INPUT

MULTIPLYING-MODE PERFORMANCE

Guaranteed monotonic LSB±1.0DNLDifferential Nonlinearity

MAX5302

Low-Power, 12-Bit Voltage-Output DAC

with Serial Interface

_______________________________________________________________________________________ 3

(Note 3)

CS = VDD, DIN = 100kHz

Rail-to-rail (Note 2)

To ±1/2LSB, V

STEP

= 2.5V

CONDITIONS

mA0.28 0.4I

Supply Current

V4.5 5.5V

Supply Voltage

nVs5Digital Feedthrough

µs20Start-Up Time

µA0.001 ±0.1Current into FB

V0 to V

Output Voltage Swing

µs14Output Settling Time

V/µs0.6SRVoltage Output Slew Rate

UNITSMIN TYP MAXSYMBOLPARAMETER

(Note 3) µA420Supply Current in Shutdown

µA0.001 ±0.5Reference Current in Shutdown

ns40t

SCLK Pulse Width High

ns100t

SCLK Clock Period

ns40t

CSS

CS Fall to SCLK Rise Setup Time

ns40t

DIN Setup Time

ns0t

CSH

SCLK Rise to CS Rise Hold Time

ns40t

SCLK Pulse Width Low

ns40t

CS1

CS Rise to SCLK Rise Hold Time

ns100t

CSW

CS Pulse Width High

ns40t

CS0

SCLK Rise to CS Fall Delay

ns0t

DIN Hold Time

Note 1: Guaranteed from code 11 to code 4095 in unity-gain configuration. Note 2: Accuracy is better than 1LSB for V

OUT

= 8mV to (V

- 100mV), guaranteed by a power-supply rejection test at the end

points.

Note 3: R

= ∞, digital inputs at GND or VDD.

DIGITAL INPUTSDYNAMIC PERFORMANCE

POWER SUPPLIES

TIMING CHARACTERISTICS (Figure 6)

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 8, VDD= +5V ±10%, V

REF

= +2.5V, RL= 5kΩ, CL= 100pF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical val-

ues are at T

= +25°C. Output buffer connected in unity-gain configuration.)

MAX5302

Low-Power, 12-Bit Voltage-Output DAC with Serial Interface

4 _______________________________________________________________________________________

-60 -20 20 60 100 140

MAX5302 toc04

POWER-DOWN SUPPLY CURRENT (µA)

POWER-DOWN SUPPLY CURRENT

vs. TEMPERATURE

TEMPERATURE (°C)

-100

0.5 1.6 3.8

OUTPUT FFT PLOT

-60

MAX5302 toc07

FREQUENCY (kHz)

2.7 4.9 6.0

-20

-40

-80

REF

= 3.6Vp-p CODE = FULL SCALE f

= 1kHz

SIGNAL AMPLITUDE (dB)

4.0 4.4 4.8 6.05.2 5.6

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX5302 toc05

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

400

350

500

450

300

250

150

100

200

-50

-90 1

100

TOTAL HARMONIC DISTORTION

PLUS NOISE vs. FREQUENCY

-85

MAX5302 toc06

FREQUENCY (kHz)

THD + NOISE (dB)

-70

-60

-55

-80

-75

-65

REF

= 2.5VDC + 1Vp-p SINE

CODE = FULL SCALE

2.49956

2.49960

2.49964

2.49968

2.49972

2.49976

2.49980

0.1k 1k 10k 1M100k

FULL-SCALE OUTPUT vs. LOAD

MAX5302 toc08

LOAD (Ω)

FULL-SCALE OUTPUT (V)

-100

0.5 1.6 3.8

REFERENCE FEEDTHROUGH

AT 1kHz

-60

MAX5302-09a/09b

FREQUENCY (kHz)

2.7 4.9 6.0

-20

-40

-80

OUTPUT FEEDTHROUGH

REFERENCE INPUT SIGNAL

SIGNAL AMPLITUDE (dB)

__________________________________________Typical Operating Characteristics

(VDD= +5V, RL= 5kΩ, CL= 100pF, TA = +25°C, unless otherwise noted.)

INL (LSB)

-0.5

0.4 1.2 2.0 2.8 3.6 REFERENCE VOLTAGE (V)

MAX5302 toc01

4.4

0.3

0.2

0.1

-0.1

-0.2

-0.3

-0.4

INTEGRAL NONLINEARITY

vs. REFERENCE VOLTAGE

-4

-8

-12

-16

-20 500k0

1M 1.5M

2M 2.5M 3M

MAX5302 toc02

RELATIVE OUTPUT (dB)

REFERENCE VOLTAGE INPUT

FREQUENCY RESPONSE

FREQUENCY (Hz)

400

380

360

340

320

300

280

260

240

220

200

-60 -20 20 60 100 140

MAX5302 toc03

SUPPLY CURRENT (µA)

SUPPLY CURRENT

vs. TEMPERATURE

TEMPERATURE (°C)

RL = ∞

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