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SI5351

I2C-Programmable Any-Frequency CMOS Clock Generator + VCXO

The SI5351 is a i2c-programmable any-frequency cmos clock generator + vcxo from Skyworks Solutions. View the full SI5351 datasheet below including key specifications, pinout, electrical characteristics, absolute maximum ratings.

Official SI5351 datasheet (PDF) — the source this page was extracted from.

SI5351 Key Specifications

ParameterValue
Power-Up Time1 ms typ, 10 ms max
Frequency Error0 ppm
Output Impedance85 Ω typ
Number Of Outputs3 (10-MSOP) or 8 (24-QSOP, 20-QFN)
Power-Down Current20 μA max
Core Supply Current22 mA typ (3 outputs enabled), 27 mA typ (8 outputs enabled)
Output Period Jitter100 ps pp
Output Frequency Range8 kHz to 160 MHz
Communication InterfaceI2C
Crystal Input Frequency25 MHz or 27 MHz
Output Phase Offset Step333 ps/step
Core Supply Voltage (VDD)2.5 V or 3.3 V (2.25V to 2.75V / 3.0V to 3.6V)
VCXO Pull Range (Si5351B)±30 to ±240 ppm
Operating Temperature Range-40°C to 85°C
Output Buffer Supply Current2.2 mA typ per output (CL = 5 pF)
Output Supply Voltage (VDDO)1.8 V, 2.5 V, or 3.3 V
Spread Spectrum Modulation Rate31.5 kHz typ

SI5351 Overview

Part: Si5351A/B/C — Silicon Labs Type: I2C-Programmable Any-Frequency CMOS Clock Generator + VCXO

Description: The Si5351 is an I2C configurable clock generator capable of generating up to 8 non-integer-related frequencies from 8 kHz to 160 MHz with 0 ppm error, using a PLL/VCXO + high resolution MultiSynth fractional divider architecture.

Operating Conditions:

  • Supply voltage (VDD): 2.25–3.6 V
  • Output buffer voltage (VDDOx): 1.71–3.6 V
  • Operating temperature: -40 to 85 °C
  • CLKIN frequency range: 10–100 MHz
  • Output frequency range: 0.008–160 MHz

Absolute Maximum Ratings:

  • Max supply voltage (VDD): 3.8 V
  • Max input voltage (CLKIN, SCL, SDA): 3.8 V
  • Max junction temperature: 150 °C

Key Specs:

  • Core supply current (3 outputs enabled): 22 mA (typ)
  • Core supply current (8 outputs enabled): 27 mA (typ)
  • Core supply current (Power Down): 20 μA (max)
  • Output buffer supply current (per output, CL=5 pF): 2.2 mA (typ)
  • Output period jitter: 100 ps pk-pk (max)
  • RMS phase jitter (12 kHz-20 MHz): 11 ps rms (max)
  • I2C standard mode speed: 100 kbps
  • I2C fast mode speed: 400 kbps

Features:

  • Generates up to 8 non-integer-related frequencies from 8 kHz to 160 MHz
  • I2C user definable configuration
  • Exact frequency synthesis at each output (0 ppm error)
  • Highly linear VCXO (Si5351B only)
  • Optional clock input (CLKIN)
  • Low output period jitter: 100 ps pp
  • Glitchless frequency changes
  • Separate voltage supply pins: Core VDD (2.5 or 3.3 V), Output VDDO (1.8, 2.5, or 3.3 V)
  • Configurable spread spectrum selectable at each output
  • Operates from a low-cost, fixed frequency crystal: 25 or 27 MHz
  • Supports static phase offset
  • Programmable rise/fall time control

Applications:

  • HDTV, DVD/Blu-ray, set-top box
  • Audio/video equipment, gaming
  • Printers, scanners, projectors
  • Residential gateways
  • Networking/communication
  • Servers, storage
  • XO replacement

Package:

  • 10-MSOP (3 outputs)
  • 24-QSOP (8 outputs)
  • 20-QFN (4x4 mm) (8 outputs)

SI5351 Features

  • Generates up to 8 non-integer-related frequencies from 8 kHz to 160 MHz
  • I 2 C user definable configuration
  • Exact frequency synthesis at each output (0 ppm error)
  • Highly linear VCXO
  • Optional clock input (CLKIN)
  • Low output period jitter: 100 ps pp
  • Glitchless frequency changes
  • Separate voltage supply pins:
  • Core VDD: 2.5 or 3.3 V
  • Output VDDO: 1.8, 2.5, or 3.3 V
  • Excellent PSRR eliminates external power supply filtering
  • Very low power consumption
  • Adjustable output-output delay
  • Configurable spread spectrum selectable at each output
  • Available in 3 packages types:
  • 10-MSOP: 3 outputs
  • Operates from a low-cost, fixed frequency crystal: 25 or 27 MHz
  • 24-QSOP: 8 outputs
  • 20-QFN (4x4 mm): 8 outputs
  • Supports static phase offset
  • Programmable rise/fall time control

SI5351 Applications

  • HDTV, DVD/Blu-ray, set-top box
  • Audio/video equipment, gaming
  • Printers, scanners, projectors

SI5351 Pin Configuration

SI5351A 20-Pin QFN Pinout

Pin NumberPin NamePin TypeFunction
1XAIInput pin for external crystal
2XBIInput pin for external crystal
3A0II²C address bit
4SCLII²C bus serial clock input. Pull-up to VDD core with 1 kΩ
5SDAI/OI²C bus serial data input. Pull-up to VDD core with 1 kΩ
6SSENISpread spectrum enable. High = enabled, Low = disabled
7OEBIOutput driver enable. Low = enabled, High = disabled
8CLK3OOutput clock 3
9CLK2OOutput clock 2
10VDDOBPOutput voltage supply pin for CLK2 and CLK3
11VDDOAPOutput voltage supply pin for CLK0 and CLK1
12CLK1OOutput clock 1
13CLK0OOutput clock 0
14VDDODPOutput voltage supply pin for CLK6 and CLK7
15CLK7OOutput clock 7
16CLK6OOutput clock 6
17CLK5OOutput clock 5
18VDDOCPOutput voltage supply pin for CLK4 and CLK5
19CLK4OOutput clock 4
20VDDPCore voltage supply pin
Center PadGNDPGround. Use multiple vias to ensure a solid path to GND

Notes

  • Part Number Clarification: The datasheet section header states "Si5351A Pin Descriptions" and covers both 20-Pin QFN and 24-Pin QSOP variants. The pinout above is for the 20-Pin QFN package as shown in the attached pin diagram labeled "Si5351A 20-QFN Top View."
  • Requested Part (SI5351): The datasheet provided covers the Si5351A variant, not the base SI5351. If a pinout for the base SI5351 exists in the full datasheet, it was not included in this excerpt. The Si5351A is the variant documented here.
  • GND Center Pad: The 20-QFN package includes a center thermal/ground pad in addition to the four corner GND pins (pins 5, 8, 17, 19 in the 24-QSOP variant). For the 20-QFN, the center pad is the primary GND connection point.

SI5351 Electrical Characteristics

Table 1. Recommended Operating Conditions

ParameterSymbolTest ConditionMinTypMaxUnit
Ambient TemperatureT A-402585°C
Core Supply VoltageV DD33.33.6V
Core Supply Voltage2.252.52.75V
Output Buffer VoltageV DDOx1.711.81.89V
Output Buffer Voltage2.252.52.75V
Output Buffer Voltage33.33.6V

Notes: All minimum and maximum specifications are guaranteed and apply across the recommended operating conditions. Typical values apply at nominal supply voltages and an operating temperature of 25 °C unless otherwise noted. VDD and VDDOx can be operated at independent voltages.

Power supply sequencing for VDD and VDDOx requires that both voltage rails are powered at the same time.

SI5351 Absolute Maximum Ratings

ParameterSymbolTest ConditionValueUnit
DC Supply VoltageV DD_max-0.5 to 3.8V
Input VoltageV IN_CLKINCLKIN, SCL, SDA-0.5 to 3.8V
Input VoltageV IN_VCVC-0.5 to (VDD+0.3)V
Input VoltageV IN_XA/BPins XA, XB-0.5 to 1.3 VV
Junction TemperatureT J-55 to 150°C
Soldering Temperature (Pb-free profile) 2T PEAK260°C
Soldering Temperature Time at TPEAK (Pb-free profile) 2T P20-40Sec
  1. Permanent device damage may occur if the absolute maximum ratings are exceeded. Functional operation should be restricted to the conditions as specified in the operational sections of this data sheet. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
  2. The device is compliant with JEDEC J-STD-020.

SI5351 Package Information

Table 14. 24-QSOP Package Dimensions

Table 14. 24-QSOP Package Dimensions

DimensionMinNomMax
A--1.75
A10.10-0.25
b0.19-0.30
c0.15-0.25
D8.558.658.75
E6.00 BSC6.00 BSC6.00 BSC
E13.813.903.99
e0.635 BSC0.635 BSC0.635 BSC
L0.40-1.27
L20.25 BSC0.25 BSC0.25 BSC
q0-8
aaa0.100.100.10
bbb0.170.170.17
ccc0.100.100.10
  1. All dimensions shown are in millimeters (mm) unless otherwise noted.
  2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
  3. This drawing conforms to the JEDEC Solid State Outline MO-137, Variation C
  4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
SI5351ASkyworks Solutions—
SI5351A-B-GUSilicon Labs—
SI5351A/B/CSkyworks Solutions Inc.—
SI5351A/CSilicon Labs—
SI5351BSkyworks Solutions—
SI5351CSkyworks Solutions—

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Data on this page is extracted from publicly available manufacturer datasheets using automated tools including AI. It may contain errors or omissions. Always verify specifications against the official manufacturer datasheet before making design or purchasing decisions. See our Terms of Service. Rights holders can submit a takedown request.

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