Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsData collecting ICsData acquisition IC - DA converter (DAC) PDIP 8

_______________General Description

The MAX522 contains two 8-bit, buffered, voltage-output

digital-to-analog converters (DAC A and DAC B) in small

8-pin SO and DIP packages. DAC A’s buffer can source

and sink 5mA, and DAC B’s output can source and sink

500µA, both to within 0.5V of ground and V

. The

MAX522 operates with a single +2.7V to +5.5V supply.

The device utilizes a 3-wire serial interface, which oper-

ates at clock rates up to 5MHz and is compatible with

SPI™, QSPI™, and Microwire™ interface standards.

The serial input shift register is 16 bits long and con-

sists of eight bits of DAC input data and eight bits for

DAC selection and shutdown control. DAC registers

can be loaded independently or in parallel at the posi-

tive edge of CS.

The MAX522’s ultra-low power consumption and small

8-pin SO package make it ideal for portable and bat-

tery-powered applications. Supply current is less than

1mA and drops below 1µA in shutdown mode. In addi-

tion, the reference input is disconnected from the REF

pin during shutdown, further reducing the system’s total

power consumption. The software format is compatible

with the MAX512/MAX513 triple 8-bit DACs.

________________________Applications

Digital Gain and Offset Adjustment

Programmable Current Source

Programmable Voltage Source

Power-Amp Bias Control

VCO Tuning

____________________________Features

♦ Operates from a Single +2.7V to +5.5V Supply

♦ Dual Buffered Voltage Output

♦ Low Power Consumption:

1mA Operating Current

<1µA Shutdown Current

♦ Independently Programmable Shutdown Mode

♦ 5MHz, 3-Wire Serial Interface

♦ SPI™, QSPI™, and Microwire™ Compatible

♦ Space-Saving 8-Pin SO Package

MAX522

Dual, 8-Bit, Voltage-Output

Serial DAC in 8-Pin SO Package

________________________________________________________________

Maxim Integrated Products

DAC

LATCH

DAC A

DAC

LATCH

DAC B

SCLK

OUTA

OUTB

DIN REF

16-BIT SHIFT REGISTER

CONTROL (8) DATA (8)

MAX522

0.1µF

0.1µF

(OPTIONAL)

0.01µF

OUTA

OUTB

GND4

0.22µF

________________Functional Diagram

OUTB

OUTA

GND

DIN

REF

SCLK

MAX522



TOP VIEW

DIP/SO

__________________Pin Configuration

Call toll free 1-800-998-8800 for free samples or literature.

19-0403; Rev 0; 6/95

PART TEMP. RANGE PIN-PACKAGE

MAX522CPA 0°C to +70°C 8 Plastic DIP

MAX522CSA 0°C to +70°C 8 SO

MAX522EPA -40°C to +85°C 8 Plastic DIP

SPI and QSPI are trademarks of Motorola Inc.

Microwire is a trademark of National Semiconductor Corp.

______________Ordering Information

MAX522ESA -40°C to +85°C 8 SO

Summary of content (12 pages)

PAGE 1
9-0403; Rev 0; 6/95 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package ____________________________Features ♦ Operates from a Single +2.7V to +5.
PAGE 2
MAX522 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package ABSOLUTE MAXIMUM RATINGS VDD to GND ................................................................ -0.3V, +6V Digital Inputs and Outputs to GND............... -0.3V, (VDD + 0.3V) REF ................................................................-0.3V, (VDD + 0.3V) OUTA, OUTB (Note 1)............................................................VDD Continuous Power Dissipation (TA = +70°C) Plastic DIP (derate 9.09mW/°C above +70°C) ........
PAGE 3
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package MAX522 ELECTRICAL CHARACTERISTICS (continued) (VDD = +2.7V to +5.5V, REF = VDD, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DYNAMIC PERFORMANCE Voltage-Output Slew Rate SR CL = 0.1µF (DAC A), CL = 0.01µF (DAC B) Voltage-Output Settling Time To ±1⁄2LSB Digital Feedthrough and Crosstalk All 0s to all 1s 0.1 CL = 0.1µF (DAC A) 70 CL = 0.
PAGE 4
__________________________________________Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) DAC B 2.0 1.5 1.0 REF = VDD = 3V CODE = ALL 1s 0 0.0001 0.001 0.01 0.1 1 10 100 DAC B 400 300 200 MAX522 TOC-02 100 0.1 1 10 0 0.0001 0.001 0.01 100 0.1 1 10 POSITIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE POSITIVE SUPPLY CURRENT vs. TEMPERATURE 1.3 1.360 1.1 IDD (mA) -20 1.0 0.9 0.7 -30 -35 96 REF = VDD = 5V ALL LOGIC INPUTS = 5V ALL DACs SET TO ALL 1s 1.345 0.
PAGE 5
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package RELATIVE OUTPUT (dB) 0 MAX522 TOC-10 REFERENCE SMALL-SIGNAL FREQUENCY RESPONSE DAC A -20 DAC B -40 -60 -80 VDD = 3V VREF = 1.5V DC WITH ±40mVP-P SINE WAVE SUPERIMPOSED 0.1k 1k 10k 100k 1M 10M FREQUENCY (Hz) LINE-TRANSIENT RESPONSE (OUTA) CLOCK FEEDTHROUGH (OUTA) A 3.14V A 2.86V B B 20µs/div REF = 2.56V, NO LOAD, CODE = ALL 1s A : VDD, 100mV/div B : OUTA, 500µV/div 1µs/div CS = HIGH A: SCLK, 333kHz, 0V TO 2.
PAGE 6
MAX522 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package ____________________________Typical Operating Characteristics (continued) (TA = +25°C, unless otherwise noted). POSITIVE SETTLING TIME (DAC A) POSITIVE SETTLING TIME (DAC B) A A B B 20µs/div 20µs/div VDD = 3V, REF = VDD, RL = 1k Ω, CL = 0.1µF, ALL BITS OFF TO ALL BITS ON VDD = 3V, REF = VDD, RL = 10k Ω, CL = 0.
PAGE 7
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package PIN NAME FUNCTION 1 –—– CS Chip Select (active low). Enables data to be shifted into the 16-bit shift register. Programming commands –—– are executed at the rising edge of C S. 2 SCLK Serial Clock Input. Data is clocked in on the rising edge of SCLK. 3 VDD Positive Power Supply (2.7V to 5.5V). Bypass with 0.22µF to GND. 4 GND Ground 5 OUTA DAC A Output Voltage (Buffered). Connect 0.1µF capacitor or greater to GND.
PAGE 8
MAX522 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package 2R 2R R 2R R 2R OUT 2R REF GND SHOWN FOR ALL 1s ON DAC Figure 1. DAC Simplified Circuit Diagram CONTROL BITS R DATA BITS Table 1.
PAGE 9
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package MAX522 CS INSTRUCTION EXECUTED SCLK OPTIONAL DIN UB1 UB2 UB3 SB SA UB4 LB LA D7 D6 D5 (CONTROL BYTE) D4 D3 D2 D1 D0 (DATA BYTE) Figure 2. MAX522 3-Wire Serial-Interface Timing Diagram Table 2.
PAGE 10
MAX522 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package CS tCSPWH tCSS tCSH tCH SCLK tCL tDS tDH DIN Figure 3. MAX522 Detailed Serial-Interface Timing Diagram Digital Inputs The digital inputs are compatible with CMOS logic. Supply current increases slightly when toggling the logic inputs through the transition zone between (0.3)(VDD) and (0.7)(VDD). Microprocessor Interfacing The MAX522 serial interface is compatible with Microwire, SPI, and QSPI.
PAGE 11
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package MAX522 ______________Applications Information The MAX522 is specified for single-supply operation with VDD ranging from 2.7V to 5.5V, covering all commonly used supply voltages in 3V and 5V systems. Initialization There is no internal power-on reset. Therefore, at power-up, perform an initial write operation to set the outputs to the desired voltage.
PAGE 12
MAX522 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO Package ________________________________________________________Package Information D E DIM E1 A A1 A2 A3 B B1 C D1 E E1 e eA eB L A3 A A2 L A1 0° - 15° C e B1 eA B eB D1 Plastic DIP PLASTIC DUAL-IN-LINE PACKAGE (0.300 in.) INCHES MAX MIN 0.200 – – 0.015 0.175 0.125 0.080 0.055 0.022 0.016 0.065 0.045 0.012 0.008 0.080 0.005 0.325 0.300 0.310 0.240 – 0.100 – 0.300 0.400 – 0.150 0.115 PKG.