Rainbow Electronics DS4026 User Manual
General description, Applications, Features

General Description
The DS4026 is a temperature-compensated crystal
oscillator (TCXO) that provides ±1ppm frequency sta-
bility over the -40°C to +85°C industrial temperature
range. Each device is factory calibrated over tempera-
ture 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 cus-
tom frequencies.
The DS4026 provides excellent phase-noise characteris-
tics. 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 pro-
vides an I
2
C 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 con-
version with a nonlinear relationship. The output from the
temperature-to-voltage converter is used to drive the volt-
age-controlled crystal oscillator to compensate for fre-
quency change.
The device implements an on-chip temperature sensor
lookup table, and a digital-to-analog converter (DAC) to
adjust the frequency. An I
2
C interface used to communi-
cate with the DS4026 performs temperature readings and
frequency push-pull.
Applications
Reference Clock Generation
Wireless
Telecom/Datacom/SATCOM
Test and Measurement
Features
♦ ±1ppm Frequency Accuracy Over -40°C to +85°C
♦ Standard Frequencies: 12.8, 19.44, 20.0, 38.88,
40.0, 51.84MHz
♦ Maximum ±4.6ppm Deviation Over 10 Years
♦ Minimum ±8ppm (±5ppm for 10MHz) Digital
Frequency Tuning Through I
2
C Interface
♦ Surface-Mount 16-Pin SO Package
♦ Pb Free/RoHS Compliant
DS4026
10MHz to 51.84MHz TCXO
______________________________________________
Maxim Integrated Products
1
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
GNDA
V
CCD
FOUT
GNDD
SCL
SDA
GND
N.C.
N.C.
TOP VIEW
SO
V
REF
V
CC
N.C.
V
OSC
GNDOSC
N.C.
N.C.
DS4026
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
PART
TEMP RANGE
OUTPUT (f
NOM
)
(MHz, CMOS)
PIN-PACKAGE
TOP MARK*
DS4026S+BCC
0°C to +70°C
12.8
16 SO
DS4026-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