Rainbow Electronics MAX5550 User Manual

General Description

The MAX5550 dual, 10-bit, digital-to-analog converter
(DAC) features high-output-current capability. The
MAX5550 sources up to 30mA per DAC, making it ideal
for PIN diode biasing applications. Outputs can also be
paralleled for high-current applications (up to 60mA
typ). Operating from a single +2.7V to +5.25V supply,
the MAX5550 typically consumes 1.5mA per DAC in
normal operation and less than 1µA (max) in shutdown
mode. The MAX5550 also features low output leakage
current in shutdown mode (±1µA max) that is essential
to ensure that the external PIN diodes are off.

Additional features include an integrated +1.25V
bandgap reference, and a control amplifier to ensure
high accuracy and low-noise performance. A separate
reference input (REFIN) allows for the use of an external
reference source, such as the MAX6126, for improved
gain accuracy. A pin-selectable I

2

C*-/SPI™-compatible
serial interface provides optimum flexibility for the
MAX5550. The maximum programmable output current
value is set using software and an adjustment resistor.

The MAX5550 is available in a (3mm x 3mm) 16-pin thin
QFN package, and is specified over the extended
(-40°C to +85°C) temperature range.

Applications

PIN Diode Biasing

RF Attenuator Control

VCO Tuning

Features

♦ Pin-Selectable I2C- or SPI-Compatible Interface

♦ Guaranteed Low Output Leakage Current in

Shutdown (±1µA max)

♦ Guaranteed Monotonic over Extended

Temperature Range

♦ Dual Outputs for Balanced Systems

♦ Current Outputs Source Up to 30mA per DAC

♦ Parallelable Outputs for 60mA Applications

♦ Output Stable with RF Filters

♦ Internal or External Reference Capability

♦ Digital Output (DOUT) Available for Daisy

Chaining in SPI Mode

♦ +2.7V to +5.25V Single-Supply Operation

♦ 16-Pin (3mm x 3mm) Thin QFN Package

♦ Programmable Output Current Range Set by

Software and Adjustment Resistor

MAX5550

Dual, 10-Bit, Programmable, 30mA

High-Output-Current DAC

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-3871; Rev 0; 10/05

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.

*Purchase of I2C components from Maxim Integrated Products,
Inc., or one of its sublicensed Associated Companies, conveys
a license under the Philips I

2

C Patent Rights to use these com-

ponents in an I

2

C system, provided that the system conforms

to the I

2

C Standard Specification as defined by Philips.

SPI is a trademark of Motorola, Inc.

+1.25V

REF

REFIN

BUFFER

10-BIT CURRENT-STEERING

DAC A

P

OUTA

V

DD

FSADJA

V

DD

OUTB

FSADJB

GND

DOUT/A1

CS/A0

DIN/SDASCLK/SCL

SPI/I2C

16-BIT INPUT REGISTER

DAC REGISTER A

DAC REGISTER B

10-BIT CURRENT-STEERING

DAC B

MAX5550

P

Functional Diagram

Pin Configuration appears at end of data sheet.

PART

MAX5550ETE

TEMP

RANGE

-40°C to
+85°C

PIN­PACKAGE

16 Thin QFN T1633F-3 ACZ

PKG

CODE

MARK

TOP

MAX5550

Dual, 10-Bit, Programmable, 30mA
High-Output-Current DAC

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

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

OUTA, OUTB to GND.................................-0.3V to (V

DD

+ 0.3V)

REFIN, CS/AO, DOUT/AI, SPI/I2C, FSADJA,

FSADJB to GND ......................................-0.3V to (V

DD

+ 0.3V)

SCLK/SCL, DIN/SDA ................................................-0.3V to +6V

Continuous Power Dissipation (T

A

= +85°C)

16-Pin Thin QFN (derate 17.5mW/°C above +70°C) ..1398.6mW

Operating Temperature Range ...........................-40°C to +85°C

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

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

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

ELECTRICAL CHARACTERISTICS

(VDD= +2.7V to +5.25V, GND = 0, V

REFIN

= +1.25V, internal reference, R

FSADJ_

= 20kΩ; compliance voltage = (VDD- 0.6V),

V

SCLK/SCL

= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VDD= +3.0V and TA= +25°C.) (Note 1)

STATIC PERFORMANCE—ANALOG SECTION

Resolution 10 Bits

Integral Nonlinearity INL I

Differential Nonlinearity DNL Guaranteed monotonic ±1 LSB

Offset I

Zero-Scale Error I

Full-Scale Error

REFERENCE

Internal Reference Range 1.21 1.25 1.29 V

Internal Reference Tempco 30 ppm/°C

External Reference Range 0.5 1.5 V

External Reference Input Current 108 225 µA

DAC OUTPUTS

Full-Scale Current (Note 3) 1 30 mA

Output Current Leakage in
Shutdown

Output Capacitance 10 pF

Current Source Dropout Voltage
(V

Output Impedance at Full-Scale
Current

Capacitive Load to Ground C

Series Inductive Load L

Maximum FSADJ_ Capacitive
Load

DYNAMIC PERFORMANCE

Settling Time t

Digital Feedthrough 2 nVs

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

- V

OUT

_)

DD

_ = 1mA to 30mA (Note 2) ±2 LSB

OUT

OS

_ = 1mA to 30mA, code = 0x000 1 µA

OUT

I

_ = 1mA to 30mA, code = 0x3FF,

OUT

includes offset

I

_ = 30mA 1

OUT

I

_ = 20mA

OUT

LOAD

LOAD

C

FSADJ_

C

S

LOAD

= 24pF, L

-50 -16 LSB

-16 LSB

±1 µA

TA = +25°C 0.55

= -40°C to +85°C 0.6

T

A

100 kΩ

10 nF

100 nH

75 pF

= 27nH (Note 4) 30 µs

LOAD

V

MAX5550

Dual, 10-Bit, Programmable, 30mA

High-Output-Current DAC

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +5.25V, GND = 0, V

REFIN

= +1.25V, internal reference, R

FSADJ_

= 20kΩ; compliance voltage = (VDD- 0.6V),

V

SCLK/SCL

= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VDD= +3.0V and TA= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Digital-to-Analog Glitch Impulse 40 nVs

DAC-to-DAC Current Matching 2%

Wake-Up Time

VDD = +3V 400

= +5V 10

V

DD

µs

POWER SUPPLIES

Supply Voltage V

Supply Current I

DD

DD

VDD = +5.25V, no load 3 6 mA

+2.70 +5.25 V

Shutdown Current 1.2 µA

LOGIC AND CONTROL INPUTS

0.7 x
V

DD

V

Input High Voltage (Note 5) V

+2.7V ≤ V

IH

DD

≤ +3.4V

+3.4V < VDD ≤ +5.25V 2.4

Input Low Voltage V

Input Hysteresis V

Input Capacitance C

Input Leakage Current I

Output Low Voltage V

Output High Voltage V

HYS

IN

OL

OH

(Note 5) 0.8 V

IL

0.1 x
V

DD

IN

I

= 3mA 0.6 V

SINK

V

I

SOURCE

= 2mA

DD

0.5

10 pF

-

V

±1 µA

V

I2C TIMING CHARACTERISTICS (Figure 2)

SCL Clock Frequency f

Setup Time for START Condition t

Hold Time for START Condition t

SCL Pulse-Width Low t

SCL Pulse-Width High t

Data Setup Time t

Data Hold Time t

SCL Rise Time t

SCL Fall Time t

SDA Rise Time t

SDA Fall Time t

SCL

SU:STA

HD:STA

LOW

HIGH

SU:DAT

HD:DAT

RCL

FCL

RDA

FDA

600 ns

600 ns

130 ns

600 ns

100 ns

070ns

20 + 0.1

x C

B

20 + 0.1

x C

B

20 + 0.1

x C

B

20 + 0.1

x C

B

400 kHz

300 ns

300 ns

300 ns

300 ns

MAX5550

Dual, 10-Bit, Programmable, 30mA
High-Output-Current DAC

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +5.25V, GND = 0, V

REFIN

= +1.25V, internal reference, R

FSADJ_

= 20kΩ; compliance voltage = (VDD- 0.6V),

V

SCLK/SCL

= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VDD= +3.0V and TA= +25°C.) (Note 1)

Note 1: 100% production tested at TA= +25°C. Limits over temperature are guaranteed by design.
Note 2: INL linearity is guaranteed from code 60 to code 1024.
Note 3: Connect a resistor from FSADJ_ to GND to adjust the full-scale current. See the Reference Architecture and Operation section.
Note 4: Settling time is measured from (0.25 x full scale) to (0.75 x full scale).
Note 5: The device draws higher supply current when the digital inputs are driven with voltages between (V

DD

- 0.5V) and (GND +

0.5V). See the Supply Current vs. Digital Input Voltage graph in the Typical Operating Characteristics.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Bus Free Time Between a STOP
and START Condition

Setup Time for STOP Condition t

Maximum Capacitive Load for
Each Bus Line

SPI TIMING CHARACTERISTICS (Figure 6)

SCLK Clock Period t

SCLK Pulse-Width High t

SCLK Pulse-Width Low t
CS Fall to SCLK Rise Setup Time t
SCLK Rise to CS Rise Hold Time t

DIN Setup Time t

DIN Hold Time t

SCLK Fall to DOUT Transition t

CS Fall to DOUT Enable t
CS Rise to DOUT Disable t
SCLK Rise to CS Fall Delay t
CS Rise to SCLK Rise Hold Time t
CS Pulse-Width High t

SPI TIMING CHARACTERISTICS FOR DAISY CHAINING (Figure 6)

SCLK Clock Period t

SCLK Pulse-Width High t

SCLK Pulse-Width Low t
CS Fall to SCLK Rise Setup Time t
SCLK Rise to CS Rise Hold Time t

DIN Setup Time t

DIN Hold Time t

SCLK Fall to DOUT Transition t

CS Fall to DOUT Enable t
CS Rise to DOUT Disable t
SCLK Rise to CS Fall Delay t
CS Rise to SCLK Rise Hold Time t
CS Pulse-Width High t

t

BUF

SU:STO

C

B

CP

CH

CL

CSS

CSH

DS

DH

C

DO1

CSE

CSD

CS0

CS1

CSW

CP

CH

CL

CSS

CSH

DS

DH

DO1

CSE

CSD

CS0

CS1

CSW

= 30pF 40 ns

LOAD

C

= 30pF 40 ns

LOAD

= 30pF 40 ns

C

LOAD

C

= 30pF 40 ns

LOAD

C

= 30pF 40 ns

LOAD

= 30pF 40 ns

C

LOAD

1.3 µs

160 ns

400 pF

100 ns

40 ns

40 ns

25 ns

50 ns

40 ns

0ns

50 ns

40 ns

100 ns

200 ns

80 ns

80 ns

25 ns

50 ns

40 ns

0ns

50 ns

40 ns

100 ns

MAX5550

Dual, 10-Bit, Programmable, 30mA

High-Output-Current DAC

_______________________________________________________________________________________ 5

Typical Operating Characteristics

(VDD= +3.0V, GND = 0, V

REFIN

= +1.25V, internal reference, R

FSADJ_

= 20kΩ, TA= +25°C. unless otherwise noted).

INL vs. CODE

2.0

1.5

1.0

0.5

0

INL (LSB)

-0.5

-1.0

-1.5

-2.0
0 128 384 640256 512 768 896 1024

CODE

DNL vs. TEMPERATURE

0.40

0.35

0.30

0.25

0.20

DNL (LSB)

0.15

0.10

0.05

0

-40 -15 10 35 60 85
TEMPERATURE (°C)

1.00

0.75

MAX5550 toc01

0.50

0.25

DNL (LSB)

-0.25

-0.50

-0.75

-1.00

MAX5550 toc04

INL (LSB)

DNL vs. CODE

0

0 128 384 640256 512 768 896 1024

CODE

MAXIMUM INL ERROR vs.

3.0

2.5

2.0

1.5

1.0

0.5

OUTPUT CURRENT RANGES

0

1–2

1.5–3 4.5–9

OUTPUT CURRENT RANGE (mA)

8–162–5

15–30

4.0

3.5

MAX5550 toc02

3.0

2.5

2.0

INL (LSB)

1.5

1.0

0.5

0

-40 -15 10 35 60 85

4.5

4.0

MAX5550 toc05

3.5

3.0

2.5

2.0

1.5

ZERO-SCALE CURRENT (nA)

1.0

0.5

0

-40 10-15 35 60 85

INL vs. TEMPERATURE

MAX5550 toc03

TEMPERATURE (°C)

ZERO-SCALE OUTPUT CURRENT

vs. TEMPERATURE

MAX5550 toc06

VDD = 5V

VDD = 3V

TEMPERATURE (°C)

FULL-SCALE CURRENT vs. TEMPERATURE

29.88

29.86

29.84

29.82

29.80

29.78

29.76

FULL-SCALE CURRENT (mA)

29.74

29.72

-40 -15 10 35 60 85

VDD = 3V

TEMPERATURE (°C)

VDD = 5V

MAX5550 toc07

SETTLING TIME

(FULL-SCALE POSITIVE STEP)

10µs/div

R
C

LOAD
LOAD

MAX5550 toc08

= 65Ω
= 24pF

CS
2V/div

V

OUT_

1V/div

SETTLING TIME

(FULL-SCALE NEGATIVE STEP)

10µs/div

R
C

LOAD
LOAD

MAX5550 toc09

= 65Ω
= 24pF

CS
2V/div

V

OUT_

1V/div