Maxim Integrated Producs DS4026S+JCN, DS4026 Datasheet

General Description

The DS4026 is a temperature-compensated crystal
oscillator (TCXO) that provides ±1ppm frequency sta­bility over the -40°C to +85°C industrial temperature
range. Each device is factory calibrated over tempera­ture to achieve the ±1ppm frequency stability. Standard
frequencies for the device include 12.8, 19.44, 20.0,

38.88, 40.0, and 51.84MHz. Contact the factory for cus­tom frequencies.

The DS4026 provides excellent phase-noise characteris­tics. The output is a push-pull CMOS square wave with
symmetrical rise and fall times. In addition, the DS4026 is
designed to provide a maximum frequency deviation of
less than ±4.6ppm over 10 years. The device also pro­vides an I2C interface to allow pushing and pulling of the
output frequency by a minimum of ±8ppm (±5ppm for
10MHz) with typical 1ppb resolution.

The DS4026 implements a temperature-to-voltage con­version with a nonlinear relationship. The output from the
temperature-to-voltage converter is used to drive the volt­age-controlled crystal oscillator to compensate for fre­quency change.

The device implements an on-chip temperature sensor
lookup table, and a digital-to-analog converter (DAC) to
adjust the frequency. An I2C interface used to communi­cate with the DS4026 performs temperature readings and
frequency push-pull.

Applications

Reference Clock Generation Wireless

Telecom/Datacom/SATCOM Test and Measurement

Features

o ±1ppm Frequency Accuracy Over -40°C to +85°C

o Standard Frequencies: 12.8, 19.44, 20.0, 38.88,

40.0, 51.84MHz

o Maximum ±4.6ppm Deviation Over 10 Years

o Minimum ±8ppm (±5ppm for 10MHz) Digital

Frequency Tuning Through I2C Interface

o Surface-Mount 16-Pin SO Package

o Pb Free/RoHS Compliant

DS4026

10MHz to 51.84MHz TCXO

______________________________________________

Maxim Integrated Products

1

Pin Configuration

Rev 1; 9/07

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

+

Denotes a lead-free package.

*

The top mark will include a “+” for a lead-free/RoHS-compliant device.

Ordering Information continued at end of data sheet.

Ordering Information

TOP VIEW

GNDA

V

REF

V

V

OSC

GNDOSC

N.C.

N.C.

N.C.

1

2

3

CC

4

DS4026

5

6

7

8

SO

16

V

CCD

15

FOUT

14

GNDD

13

SCL

12

SDA

GND

11

10

N.C.

9

N.C.

PART TEMP RANGE

DS4026S+BCC

DS4026S+BCN -40°C to +85°C 12.8 16 SO DS4026-BCN

DS4026S+HCC 0°C to +70°C 19.44 16 SO DS4026-HCC

DS4026S+HCN -40°C to +85°C 19.44 16 SO DS4026-HCN

DS4026S+JCC 0°C to +70°C 20.0 16 SO DS4026-JCC

DS4026S+JCN -40°C to +85°C 20.0 16 SO DS4026-JCN

0°C to +70°C 12.8 16 SO DS4026-BCC

OUTPUT (f

(MHz, CMOS)

NOM

)

PIN-PACKAGE TOP MARK*

DS4026

10MHz to 51.84MHz TCXO

2 _____________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

RECOMMENDED DC OPERATING CONDITIONS

(TA= -40°C to +85°C, unless otherwise noted.)

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.

Voltage Range on V

CC

,

V

CCD

, and V

OSC

Relative to Ground..............................................-0.3V to +3.8V

Voltage Range on SDA, SCL, and FOUT

Relative to Ground...................................-0.3V to (V

CC

+ 0.3V)

Operating Temperature Range (noncondensing)....-40°C to +85°C

Storage Temperature Range .............................-55°C to +125°C

Soldering Temperature………………………….See IPC/JEDEC

J-STD-020 Specification

DC ELECTRICAL CHARACTERISTICS (Note 1)

(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Notes 2, 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Power-Supply Voltage V

Oscillator Power Supply V

Driver Power Supply V

CC

OSC

CCD

VCC Active-Supply Current I

V

OSC

Current

V

CCD

Current

SCL Input Leakage I

SDA Leakage I

SCL, SDA High Input Voltage V

SCL, SDA Low Input Voltage V

SDA Logic 0 Output I

FOUT High Output Voltage V

FOUT Low Output Voltage V

FOUT Rise/Fall Time tR/t

FOUT Duty Cycle t

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CC

(Note 4) 1.5 2.5 mA

FOUT CMOS output on, CL = 10pF,

Oscillator Active-Supply

I

OSC

frequency < 25MHz

FOUT CMOS output on, CL = 10pF,
frequency ≥ 25MHz

FOUT CMOS output on, CL = 10pF,

Driver Active-Supply

I

CCD

frequency < 25MHz

FOUT CMOS output on, CL = 10pF,
frequency ≥ 25MHz

LI

LO

OL

OH

OL

Output off -1 +1 µA

IH

IL

VCC = 3.0V, VOL = 0.4V 3 mA

V

= 3V, IOH = -2mA 2.4 V

CCD

V

= 3V, IOL = 2.0mA 0.4 V

CCD

(0.1 x V

F

D

0.5 x V

CCD

CCD

3.135 3.3 3.465 V

3.135 3.3 3.465 V

3.135 3.3 3.465 V

34

59

23

35

-1 +1 µA

) - (0.9 x V

0.7 x
V

CC

-0.3

)2ns

CCD

V

CC

+ 0.3

+0.3 x

V

CC

(Note 5) 45 55 %

mA

mA

V

V

DS4026

10MHz to 51.84MHz TCXO

_____________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS (Note 1)

(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.)

PHASE NOISE

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Frequency Stability vs.
Temperature

Frequency Stability vs. Voltage Δf1/V CL = 10pF to ground, +25°C -2 +2 ppm/V

Aging, First Year Δf1/Yr (Note 5) -1 +1 ppm

Aging, Years 2–15 Δf1/Yr (Note 5) -2 +2 ppm

Frequency Pull
Range

Frequency Pull Resolution Δf

Except 10MHz ±8 ±15

10MHz

Δf

1/TA

Δf

RES

CL = 10pF to ground

FTU N E H = 3Fh and FTU N E L = FFh;
FTU N E H = 40h and FTU N E L = 00h at + 25° C

f

NOM

– 1ppm

±5 ±10

f

NOM

f

NOM

+ 1ppm

1 ppb

ppm

ppm

PHASE NOISE (dBc/Hz) (TYPICAL, +25°C, 3.3V)

OFFSET (MHz) 10Hz 100Hz 1kHz 10kHz 100kHz 1MHz

12.80 -88.41 -130.16 -147.84 -150.84 -151.71 -151.87

19.44 -82.63 -125.12 -145.03 -146.87 -151.69 -151.52

20.00 -83.71 -120.76 -145.44 -150.96 -151.18 -151.45

CARRIER

FREQUENCY

38.88 -79.01 -120.06 -141.75 -150.59 -152.50 -153.06

40.00 -80.80 -115.44 -141.17 -151.59 -152.37 -153.00

51.84 -74.09 -120.39 -142.33 -151.14 -153.21 -153.94

10.0 -92.52 -134.83 -147.22 -150.84 -151.25 -150.84

16.384 -87.44 -128.53 -147.67 -150.78 -152.72 -151.75

16.8 -89.6 -126.20 -146.88 -151.90 -152.28 -151.93

24.0 -83.98 -119.45 -143.08 -150.33 -150.34 -150.67

DS4026

10MHz to 51.84MHz TCXO

4 _____________________________________________________________________

TEMPERATURE SENSOR ELECTRICAL CHARACTERISTICS (Note 1)

(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.)

AC ELECTRICAL CHARACTERISTICS

(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 2)

PARAMETER S YMBOL CONDITIONS MIN TYP MAX UNITS

Temperature Sensor Accuracy T -3 +3 °C

Temperature Sensor Convers ion
Time

Temperature Sensor Resolution N2 12 Bits

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

SCL Clock Frequency f

Bus Free Time Between STOP
and START Conditions

Hold Time (Repeated) START
Condition (Note 6)

Low Period of SCL Clock t

High Period of SCL Clock t

Data Hold Time
(Notes 7, 8)

Data Setup Time (Note 9) t

Start Setup Time t

Rise Time of Both SDA and SCL
Signals (Note 10)

Fall Time of Both SDA and SCL
Signals (Note 10)

t

11 ms

CONVT

SCL

t

BUF

t

HD:STA

LOW

HIGH

t

HD:DAT

SU:DAT

SU:STA

t

t

Standard mode 0 100

Fast mode 100 400

Standard mode 4.7

Fast mode 1.3

Standard mode 4.0

Fast mode 0.6

Standard mode 4.7

Fast mode 1.3

Standard mode 4.0

Fast mode 0.6

Standard mode 0 0.9

Fast mode 0 0.9

Standard mode 250

Fast mode 100

Standard mode 4.7

Fast mode 0.6

Standard mode 20 + 0.1C

R

Fast mode 20 + 0.1C

Standard mode 20 + 0.1C

F

Fast mode 20 + 0.1C

B

B

B

B

1000

300

300

300

kHz

µs

µs

µs

µs

µs

ns

µs

ns

ns