DS4026S+ACN ,10MHz to 51.84MHz TCXOApplicationsN.C. 8 9 N.C.Reference Clock Generation WirelessTelecom/Datacom/SATCOM Test and Measure ..
DS4026S+BCN ,10MHz to 51.84MHz TCXOELECTRICAL CHARACTERISTICS(V = 3.135V to 3.465V, T = -40°C to +85°C, unless otherwise noted.) (Note ..
DS4026S+FCN ,10MHz to 51.84MHz TCXODS4026Rev 2; 4/0810MHz to 51.84MHz TCXO
DS4026S+HCN ,10MHz to 51.84MHz TCXOELECTRICAL CHARACTERISTICS—TCXO(V = 3.135V to 3.465V, T = -40°C to +85°C, unless otherwise noted.) ..
DS4026S+JCN ,10MHz to 51.84MHz TCXOFeaturesThe DS4026 is a temperature-compensated crystal♦ ±1ppm Frequency Accuracy Over -40°C to +85 ..
DS4026S+MCN ,10MHz to 51.84MHz TCXOELECTRICAL CHARACTERISTICS(V = 3.135V to 3.465V, T = -40°C to +85°C, unless otherwise noted.) (Note ..
EC2-12NU ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
EC2-24 ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
EC2-24NU ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
EC2-4.5NJ ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
EC2-4.5NU ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
EC2-4.5TNU ,COMPACT AND LIGHTWEIGHT, SMALL MOUNTING SIZE, HIGH BREAKDOWN VOLTAGE
DS4026S+ACN-DS4026S+BCN-DS4026S+FCN-DS4026S+HCN-DS4026S+JCN-DS4026S+MCN-DS4026S+PCN-DS4026S+QCN-DS4026S+RCN
10MHz to 51.84MHz TCXO
General DescriptionThe DS4026 is a temperature-compensated crystal
oscillator (TCXO) that provides ±1ppm frequency stabili-
ty over the -40°C to +85°C industrial temperature range.
The DS4026 is also available in Stratum 3 versions (see
the Ordering Information—Stratum 3table). Each device
is factory calibrated over temperature to achieve the
±1ppm frequency stability. Standard frequencies for the
device include 10, 12.8, 19.44, 20, 38.88, 40, and
51.84MHz. Contact the factory for custom 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 20 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 con-
version 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 commu-
nicate with the DS4026 performs temperature readings
and frequency push-pull.
ApplicationsReference Clock GenerationWireless
Telecom/Datacom/SATCOMTest and Measurement
Features±1ppm Frequency Accuracy Over -40°C to +85°CStandard Frequencies: 10, 12.8, 19.44, 20, 38.88,
40, 51.84MHzStratum 3 Frequencies: 10, 12.8, 19.2, 20MHzMaximum ±4.6ppm Deviation Over 20 YearsMinimum ±8ppm (±5ppm for 10MHz) Digital
Frequency Tuning Through I2C InterfaceSurface-Mount 16-Pin SO PackagePb Free/RoHS Compliant
DS4026
10MHz to 51.84MHz TCXOGNDAVCCD
FOUT
GNDD
SCL
SDA
GND
N.C.
N.C.
TOP VIEW
VREF
VCC
N.C.
VOSC
GNDOSC
N.C.
N.C.
DS4026
Pin ConfigurationRev 2; 4/08
+Denotes a lead(Pb)-free/RoHS-compliant package.
*The top mark will include a “+” for a lead(Pb)-free/RoHS-compliant device.
Ordering Information continued at end of data sheet.
Ordering Information
PART TEMP RANGE OUTPUT (fC)
(MHz, CMOS) PIN-PACKAGE TOP MARK*DS4026S+ACC 0°C to +70°C 10.00 16 SO DS4026-ACC
DS4026S+ACN -40°C to +85°C 10.00 16 SO DS4026-ACN
DS4026S+BCC 0°C to +70°C 12.80 16 SO DS4026-BCC
DS4026S+BCN -40°C to +85°C 12.80 16 SO DS4026-BCN
DS4026S+ECC 0°C to +70°C 16.80 16 SO DS4026-ECC
DS4026S+ECN -40°C to +85°C 16.80 16 SO DS4026-ECN
DS4026S+FCC 0°C to +70°C 16.384 16 SO DS4026-FCC
DS4026S+FCN -40°C to +85°C 16.384 16 SO DS4026-FCN
DS4026
10MHz to 51.84MHz TCXO
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 VCC, VCCD, and VOSC
Relative to Ground..............................................-0.3V to +3.8V
Voltage Range on SDA, SCL, and FOUT
Relative to Ground...................................-0.3V to (VCC+ 0.3V)
Operating Temperature Range (noncondensing)....-40°C to +85°C
Storage Temperature Range...............................-40°C to +85°C
Soldering Temperature...........................Refer to the IPC/JEDEC
J-STD-020 Specification.
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSPower-Supply Voltage VCC 3.135 3.3 3.465 V
Oscillator Power Supply VOSC3.1353.33.465V
Driver Power Supply VCCD3.135 3.3 3.465 V
DC ELECTRICAL CHARACTERISTICS(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Notes 1, 2, 3)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS VCC Active-Supply Current ICC (Note 4) 1.5 2.5 mA
FOUT CMOS output on, CL = 10pF,
frequency < 25MHz 3 4 VOSC Oscillator Active-Supply
Current IOSC
FOUT CMOS output on, CL = 10pF,
frequency 25MHz 5 9
mA
FOUT CMOS output on, CL = 10pF,
frequency < 25MHz 2 3
VCCD Driver Active-Supply
Current ICCD
FOUT CMOS output on, CL = 10pF,
frequency 25MHz 3 5
mA
SCL Input Leakage ILI -1 +1 μA
SDA Leakage ILO Output off -1 +1 μA
SCL, SDA High Input Voltage VIH0.7 x
VCC
VCC
+ 0.3 V
SCL, SDA Low Input Voltage VIL -0.3 +0.3 x
VCCV
SDA Logic 0 Output IOL VCC = 3.0V, VOL = 0.4V 3 mA
FOUT High Output Voltage VOH VCCD = 3V, IOH = -2mA 2.4 V
FOUT Low Output Voltage VOL VCCD = 3V, IOL = 2.0mA 0.4 V
FOUT Rise/Fall Time tR/tF (0.1 x VCCD) - (0.9 x VCCD) 2 ns
FOUT Duty Cycle tD 0.5 x VCCD (Note 5) 45 55 %
DS4026
10MHz to 51.84MHz TCXO
AC ELECTRICAL CHARACTERISTICS—TCXO(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS Frequency Stability vs.
Temperature f/fC CL = 10pF to groundfC
– 1ppm fCfC
+ 1ppm ppm
Frequency Stability vs. Voltage fVOLTAGE
/fCCL = 10pF to ground, +25°C -2 +2 ppm/V
First Year -1 +1 Aging Years 2–20 fAGING/fC (Note 5) -2 +2 ppm
Except 10MHz ±8 ±15 Frequency Pull
Range 10MHz f/fCFTUNEH = 3Fh and FTUNEL = FFh;
FTUNEH = 40h and FTUNEL = 00h at +25°C ±5 ±10 ppm
Frequency Pull Resolution fRES/fC 1 ppb
AC ELECTRICAL CHARACTERISTICS—STRATUM 3(VCC= +3.135V to +3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
STRATUM 3 FREQUENCY STABILITYFrequency Stability vs.
Temperature fTEMP/fC -40°C to +85°C (Note 6) -0.28 +0.28 ppm
Initial Tolerance and Reflow fINITIAL /fC TA = +25°C, ±3°C and VDD = 3.3V-0.8 +0.8 ppm
Frequency Stability vs. Voltage fVOLTAGE
/fC
VCC = 3.3V ±5%, CL = 10pF to ground,
+25°C (Note 7) -0.33 +0.33 ppm
Frequency Stability vs.
Aging/20 Years fAGING/fC fC = Nominal (Note 8) -3.0 +3.0 ppm
Frequency Stability vs. Load
Change fLOAD/fC Load = 10pF ±5%, +25°C (Note 5) -0.1 +0.1 ppm
Free-Run Accuracy Operating temperature, load, supply, and
initial tolerance, aging (20 years) (Notes 5, 8) -4.6 +4.6 ppm
Holdover Stability (24 Hours) f24HOURS
/fC24-hour elapsed time (Notes 5, 9) -0.32 +0.32 ppm
PHASE NOISE
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
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
CARRIER
FREQUENCY
AC ELECTRICAL CHARACTERISTICS—I2C SERIAL INTERFACE(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSStandard mode 0 100 SCL Clock Frequency fSCLFast mode 100 400 kHz
Standard mode 4.7 Bus Free Time Between STOP
and START Conditions tBUFFast mode 1.3 μs
Standard mode 4.0 Hold Time (Repeated) START
Condition (Note 10) tHD:STAFast mode 0.6 μs
Standard mode 4.7 Low Period of SCL Clock tLOWFast mode 1.3 μs
Standard mode 4.0 High Period of SCL Clock tHIGHFast mode 0.6 μs
Standard mode 0 0.9 Data Hold Time
(Notes 11, 12) tHD:DAT
Fast mode 0 0.9
μs
Standard mode 250 Data Setup Time (Note 13) tSU:DATFast mode 100 ns
Standard mode 4.7 START Setup Time tSU:STAFast mode 0.6 μs
Standard mode 20 + 0.1CB 1000 Rise Time of Both SDA and SCL
Signals (Note 14) tRFast mode 20 + 0.1CB 300 ns
Standard mode 20 + 0.1CB 300 Fall Time of Both SDA and SCL
Signals (Note 14) tFFast mode 20 + 0.1CB 300 ns
Standard mode 4.7 Setup Time for STOP Condition tSU:STOFast mode 0.6 μs
Pin Capacitance SDA, SCL
(Note 5) CI/O 10 pF
DS4026
10MHz to 51.84MHz TCXO
TEMPERATURE SENSOR ELECTRICAL CHARACTERISTICS(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS Temperature Sensor Accuracy T -3 +3 °C
Temperature Sensor Conversion
Time tCONVT 11 ms
Temperature Sensor Resolution N2 12 Bits
DS4026
Note 1:Typical values are at +25°C, nominal supply voltages, unless otherwise indicated.
Note 2:Voltages referenced to ground.
Note 3:Limits at -40°C are guaranteed by design and not production tested.
Note 4:Specified with I2C bus inactive.
Note 5:Guaranteed by design and not production tested.
Note 6:Frequency stability vs. temperature is defined as (ΔfMAX- ΔfMIN)/2.
Note 7:Maximum power-supply variations to meet the specification are 5%.
Note 8:Crystal vendor specification.
Note 9:Holdover is defined as (fMAX- fMIN)/2 as measured within a 24-hour period. Warmup time = 1 hour.
Note 10:After this period, the first clock pulse is generated.
Note 11:A device must internally provide a hold time of at least 300ns for the SDA signal (referred to the VIH(MIN)of the SCL signal)
to bridge the undefined region of the falling edge of SCL.
Note 12:The maximum tHD:DATneed only be met if the device does not stretch the low period (tLOW) of the SCL signal.
Note 13:A fast-mode device can be used in a standard-mode system, but the requirement that tSU:DAT≥250ns must then be met.
This is automatically the case if the device does not stretch the low period of the SCL signal. If such a device does not
stretch the low period of the SCL signal, it must output the next data bit to the SDA line tR(MAX)+ tSU:DAT= 1000 + 250 =
1250ns before the SCL line is released.
Note 14:CB—total capacitance of one bus line in pF.
AC ELECTRICAL CHARACTERISTICS—I2C SERIAL INTERFACE (continued)(VCC= 3.135V to 3.465V, TA= -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSCapacitive Load for Each Bus
Line (Note 14) CB 400 pF
Pulse Width of Spikes That Must
Be Suppressed by the Input
Filter
tSP Fast mode 30 ns
10MHz to 51.84MHz TCXO
Data Transfer on I2C Serial BusSDA
SCL
tHD:STA
tLOW
tHIGHtF
tBUF
tHD:DAT
tSU:DATREPEATED
START
tSU:STA
tHD:STA
tSU:STO
tSP
STOPSTART
DS4026
10MHz to 51.84MHz TCXO
Typical Operating Characteristics(VCC= +3.3V, TA = +25°C, unless otherwise noted.)
ACTIVE-SUPPLY CURRENT
vs. POWER-SUPPLY CURRENTDS4026 toc01
VCC (V)
CURRENT (mA)
ACTIVE-SUPPLY CURRENT
vs. OSCILLATOR POWER SUPPLY
DS4026 toc02
VOSC (V)
CURRENT (mA)
ACTIVE-SUPPLY CURRENT
vs. DRIVER POWER SUPPLY
DS4026 toc03
VCCD (V)
CURRENT (mA)
FREQUENCY vs. FTUNE
DS4026 toc04
VC (V)
OFFSET (ppm)
000h4000h
3FFFh
FREQUENCY vs. TEMPERATURE
DS4026 toc05
TEMPERATURE (°C)
DEVIATION (ppm)40200-20
DCOMP = 1
DCOMP = 0
PHASE NOISE (TYP)DS4026 toc06
OFFSET (Hz)
PHASE NOISE (dBc/Hz)
-180.0100100010,000100,0001,000,000
51.84MHz
12.8MHz
19.44MHz
38.88MHz
DS4026
10MHz to 51.84MHz TCXOGNDA
0.1μF
0.1μF
0.1μF
20Ω
VREF
100μF ±20%
CERAMIC
3.3V
3.3V
3.3V ±5%
VCC
VOSC
GNDOSC
N.C.
N.C.
N.C.
VCCD
FOUT
GNDD
SCL
SDA
GND
N.C.
N.C.
DS4026
Pin Description
PINNAMEFUNCTION GNDA Ground for DAC
2 VREF Voltage Reference Output. This pin must be decoupled with a 100μF ceramic capacitor to ground.
3 VCCPower Supply for Digital Control and Temperature Sensor. This pin must be decoupled with a
100nF capacitor to ground.
4 VOSC Power Supply for Oscillator Circuit. This pin must be decoupled with a 0.1μF capacitor to ground.
5 GNDOSC Ground for Oscillator Circuit
6–10 N.C. No Connection. Must be connected to ground.
11 GND Ground for Digital Control, Temperature Sensor, and Controller Substrate
12 SDA Serial Data Input/Output. SDA is the data input/output for the I2C interface. This open-drain pin
requires an external pullup resistor.
13 SCL Serial Clock Input. SCL is the clock input for the I2C Interface and is used to synchronize data
movement on the serial interface.
14 GNDD Ground for Oscillator Output Driver
15 FOUT Frequency Output, CMOS Push-Pull
16 VCCDPower Supply for Oscillator Output Driver. This pin must be decoupled with a 0.1μF capacitor to
ground. A 20 resistor must be placed in series between the power supply and VCCD.
Figure 1. Typical Operating Circuit
