Rainbow Electronics MAX5821 - Manual

General Description
The MAX5822 is a dual, 12-bit, voltage-output, digital-to-
analog converter (DAC) with an I
2 C ™ -compatible, 2-wire
interface that operates at clock rates up to 400kHz. The
device operates from a single 2.7V to 5.5V supply and
draws only 115µA at V
DD = 3.6V. A power-down mode
decreases current consumption to less than 1µA. The
MAX5822 features three software-selectable power-
down output impedances: 100k
Ω, 1kΩ, and high imped-
ance. Other features include internal precision
Rail-to-Rail
® output buffers and a power-on reset (POR)
circuit that powers up the DAC in the 100k Ω power-down
mode.
The MAX5822 features a double-buffered I
2 C-compatible
serial interface that allows multiple devices to share a
single bus. All logic inputs are CMOS-logic compatible
and buffered with Schmitt triggers, allowing direct inter-
facing to optocoupled and transformer-isolated inter-
faces. The MAX5822 minimizes digital noise feedthrough
by disconnecting the clock (SCL) signal from the rest of
the device when an address mismatch is detected.
The MAX5822 is specified over the extended tempera-
ture range of -40°C to +85°C and is available in a minia-
ture 8-pin µMAX package. Refer to the MAX5821 data
sheet for the 10-bit version.
Applications
Digital Gain and Offset Adjustments
Programmable Voltage and Current Sources
Programmable Attenuation
VCO/Varactor Diode Control
Low-Cost Instrumentation
Battery-Powered Instrumentation
Features
♦ Ultra-Low Supply Current
115µA at V DD = 3.6V
135µA at V
DD
= 5.5V
♦ 300nA Low-Power Power-Down Mode
♦ Single 2.7V to 5.5V Supply Voltage
♦ Fast 400kHz I
2 C-Compatible 2-Wire Serial
Interface
♦ Schmitt-Trigger Inputs for Direct Interfacing to
Optocouplers
♦ Rail-to-Rail Output Buffer Amplifiers
♦ Three Software-Selectable Power-Down Output
Impedances
100k Ω, 1kΩ, and High Impedance
♦ Read-Back Mode for Bus and Data Checking
♦ Power-On Reset to Zero
♦ 8-Pin µMAX Package
MAX5822
Dual, 12-Bit, Low-Power, 2-Wire, Serial
Voltage-Output DAC
________________________________________________________________ Maxim Integrated Products 1
REF
SDA SCL
1
2
8
7
OUTB
OUTA GND
ADD
V
DD
µMAX
TOP VIEW
3
4
6
5
MAX5822
Pin Configuration
Ordering Information
R P
R P
V DD
µC
SDA SCL
SDA
SDA
REF
REF
REF
SCL
SCL
V DD
V DD
R S
R S
V DD
OUTA
OUTB
OUTA
OUTB
MAX5822
MAX5822
R S
R S
Typical Operating Circuit
19-2315; Rev 0; 1/02
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART
TEMP
RANGE
PIN-
PACKAGE
ADDRESS
MAX5822LEUA -40 o C to +85 o C 8 µMAX 0111 00X
MAX5822MEUA -40 o C to +85 o C 8 µMAX 1011 00X
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
I
2 C is a trademark of Philips Corp.