Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsData collecting ICsData acquisition IC - DA converter (DAC) SOT 23 8

General Description

The MAX5222 contains two 8-bit, buffered, voltage-out-

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

small 8-pin SOT23 package. Both DAC outputs can

source and sink 1mA to within 100mV of ground and

. The MAX5222 operates with a single +2.7V to

+5.5V supply.

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

ates at clock rates up to 25MHz and is compatible with

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

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

sists of 8 bits of DAC input data and 8 bits for DAC

selection and shutdown control. DAC registers can be

loaded independently or in parallel at the positive edge

of CS.

The MAX5222’s ultra-low power consumption and tiny

8-pin SOT23 package make it ideal for portable and

battery-powered applications. Supply current is less

than 1mA and drops below 1µA in shutdown mode. In

addition, the reference input is disconnected from the

REF pin during shutdown, further reducing the system’s

total power consumption.

________________________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

♦ Tiny 8-Pin SOT23 Package (3mm

3mm)

♦ Dual Buffered Voltage Output

♦ Low Power Consumption

0.4mA Operating Current

<1µA Shutdown Current

♦ Programmable Shutdown Mode

♦ 25MHz, 3-Wire Serial Interface

♦ SPI, QSPI, and MICROWIRE Compatible

MAX5222

Dual, 8-Bit, Voltage-Output

Serial DAC in 8-Pin SOT23

________________________________________________________________ Maxim Integrated Products 1

DAC

LATCH

DAC A

DAC

LATCH

DAC B

SCLK

OUTA

OUTB

DIN REF

16-BIT SHIFT REGISTER

CONTROL (8) DATA (8)

MAX5222

0.1µF

(OPTIONAL)

OUTA

OUTB

GND2

0.22µF

Functional Diagram

OUTB

OUTA

SCLK

DIN

REF

GND

MAX5222

TOP VIEW

SOT23-8

Pin Configuration

19-1720; Rev 0; 4/00

PART TEMP. RANGE PIN-PACKAGE

MAX5222EKA-T -40°C to +85°C 8 SOT23-8

SPI and QSPI are trademarks of Motorola, Inc.

MICROWIRE is a trademark of National Semiconductor Corp.

Ordering Information

For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.

For small orders, phone 1-800-835-8769.

Summary of content (12 pages)

PAGE 1
9-1720; Rev 0; 4/00 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 The MAX5222’s ultra-low power consumption and tiny 8-pin SOT23 package make it ideal for portable and battery-powered applications. Supply current is less than 1mA and drops below 1µA in shutdown mode. In addition, the reference input is disconnected from the REF pin during shutdown, further reducing the system’s total power consumption. Features ♦ Operates from a Single +2.7V to +5.
PAGE 2
MAX5222 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 ABSOLUTE MAXIMUM RATINGS VDD to GND ............................................................. -0.3V to +6V All Other Pins to GND (Note 1).................. -0.3V to (VDD + 0.3V) Continuous Power Dissipation (TA = +70°C) 8-Pin SOT23 (derate 8.7mW/°C above +70°C)............696mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................
PAGE 3
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 MAX5222 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 CL = 100pF 1 V/µs Voltage-Output Settling Time SR To ±1⁄2LSB, CL = 100pF 10 µs Digital Feedthrough and Crosstalk All 0s to all 1s 0.
PAGE 4
__________________________________________Typical Operating Characteristics (VDD = +3V, TA = +25°C, unless otherwise noted.) 3.0 OUTPUT VOLTAGE vs. OUTPUT SINK CURRENT 800 MAX5222-02 6 MAX5222-01 3.5 OUTPUT VOLTAGE vs. OUTPUT SOURCE CURRENT (VDD = 5V) 5 MAX5222-03 OUTPUT VOLTAGE vs. OUTPUT SOURCE CURRENT (VDD = 3V) 700 2.0 1.5 1.0 OUTPUT VOLTAGE (mV) 2.5 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) 600 4 3 2 500 400 300 200 100 1 0.5 0 0.01 0.1 1 10 0 0.0001 100 0.01 1 -100 0.
PAGE 5
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 LARGE-SIGNAL OUTPUT STEP RESPONSE CLOCK FEEDTHROUGH MAX5222-10 MAX5222-11 VREF = VDD = 3V, RL = 10kΩ, CL = 100pF CH1 CH1 SCLK, 5MHz 0 TO 2.
PAGE 6
MAX5222 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 Typical Operating Characteristics (continued) (VDD = +3V, TA = +25°C, unless otherwise noted.
PAGE 7
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 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 GND Ground 3 VDD Positive Power Supply (+2.7V to +5.5V). Bypass with 0.22µF to GND. 4 SCLK Serial Clock Input. Data is clocked in on the rising edge of SCLK.
PAGE 8
MAX5222 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 R 2R 2R R 2R R 2R OUT 2R DATA BITS Table 1. Input Shift Register SHOWN FOR ALL 1s ON DAC Figure 1. DAC Simplified Circuit Diagram Serial Interface –—– An active-low chip select (CS) enables the shift register to receive data from the serial data input. Data is clocked into the shift register on every rising edge of the serial clock signal (SCLK). The clock frequency can be as high as 25MHz.
PAGE 9
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 MAX5222 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. 3-Wire Serial-Interface Timing Diagram Table 2.
PAGE 10
MAX5222 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 CS tCSPWH tCSS tCSH tCH SCLK tCL tDS tDH DIN Figure 3. 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 MAX5222 serial interface is compatible with MICROWIRE, SPI, and QSPI.
PAGE 11
Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 MAX5222 Applications Information The MAX5222 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 An internal power-on reset circuit forces the outputs to zero scale and initializes all external registers to zero. This is equivalent to being in the shutdown state.
PAGE 12
________________________________________________________Package Information SOT23, 8L.EPS MAX5222 Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SOT23 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.