ICS271PG - Triple PLL VCXO Clock Synthesizer | Renesas
MPN: ICS271PG ✗ End of LifeICS271PG Overview
A VCXO, or voltage-controlled crystal oscillator, is a clock-generation technique in which an oscillator’s frequency can be controlled by an external voltage. A field-programmable VCXO clock synthesizer extends that concept by combining crystal-referenced timing with programmable phase-locked loops and selectable output divisions. Within the broader hierarchy, the ICS271PG belongs to the clock and timing IC category, specifically the PLL and frequency-synthesizer class, and can replace multiple discrete crystal and oscillator arrangements when system designers need several related frequencies from one reference.
Key features include three PLL capability, up to six generated clock outputs, a maximum frequency of 200 MHz, CMOS output logic, crystal input, and PLL bypass operation. The six-output architecture supports systems that need both reference clocks and higher-frequency working clocks. Field programming allows the device to be configured for different output requirements, while PLL bypass provides a path for systems that need to select between synthesized and direct-reference operating conditions during design or validation.
Technically, the ICS271PG uses a crystal-referenced architecture with programmable PLL and output stages. The low-frequency crystal source establishes a stable reference from which the internal synthesis circuitry can derive multiple clock outputs. CMOS output signaling supports integration with digital logic operating in the same clock domain. Because the device is controlled through VersaClock software according to its documentation, configuration should be completed with the intended output frequencies, divider relationships, and operating modes validated together rather than selected independently.
Typical applications include communications equipment, interface controllers, digital signal processing systems, test and measurement instruments, and embedded systems that require several coordinated clock outputs. It can also serve clock-distribution designs where a central synthesizer offers a more scalable alternative to multiple separately sourced oscillators. In each case, the main design benefits are centralized referenceing and programmable output relationships.
The primary design consideration is preserving clean, deterministic clock behavior across every enabled output. Use the manufacturer’s configuration procedure, validate each output against its assigned load, and check startup and bypass transitions with the final system timing budget. PCB layout should follow the datasheet guidance for crystal connections, supply decoupling, and output routing to minimize jitter and crosstalk.
This page organizes the device’s clock-generation characteristics, drop-in candidate listings, application guidance, and engineering design considerations. It is intended to help engineers compare the ICS271PG with equivalent field-programmable clock synthesizers before committing to a board design or production sourcing plan.
Drop-in alternatives for ICS271PG — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
ICS271PGILF
✅ Drop-In📋 Reference alternative (not in catalog)
271PGLF
✅ Drop-In📋 Reference alternative (not in catalog)
ICS271PG Specifications
| Device Type | Clock/Frequency Synthesizer, Fanout Buffer (Distribution) |
| Architecture | Triple PLL Field Programmable VCXO Clock Synthesizer |
| PLL Count | 3 PLLs |
| PLL Bypass | Supported |
| Input Type | Crystal |
| Output Type | CMOS |
| Maximum Frequency | 200 MHz |
| Number of Circuits | 1 |
| Maximum Output Count | 6 outputs |
| Package | 20-pin TSSOP |
| Mounting Type | Surface Mount |
| Configuration Interface | IDT VersaClock software |
| One-Time Programmable Configuration | Supported |
ICS271PG 20-pin tssop Pin Configuration Guide
Pin configuration for ICS271PG (20-pin tssop package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for ICS271PG.
Refer to the datasheet for full pin configuration.
Typical Applications
ICS271PG is suitable for 6 applications: Communications Equipment Clocking, Digital Signal Processing Platforms, Test and Measurement Instrumentation, Industrial Control and Data Acquisition, Interface and Serialization Clocking, Embedded System Timing Hub.
Communications Equipment Clocking
The ICS271PG fits communications equipment that needs several related clocks rather than multiple independent oscillators. Its three PLLs can support up to six CMOS outputs, while the 200 MHz maximum frequency provides headroom for digital processing, interface, and control logic. A crystal reference can establish the system timing foundation, and field programming allows output frequencies and divider relationships to be configured for the final architecture. Designers should confirm the required channel-to-channel phase relationship, output jitter, load, and timing margins against the device configuration before release to production.
Recommended
Digital Signal Processing Platforms
The ICS271PG is appropriate for digital signal processing platforms that require a centralized clock-reference structure. Three PLLs and up to six outputs can organize reference, processing, conversion, and interface domains from one low-frequency crystal input. Its CMOS outputs suit conventional digital clock distribution, while the 200 MHz ceiling supports demanding synchronous logic. For a DSP-based design, evaluate each output against the processor’s permitted frequency range and create the timing budget from the actual programmed output relationships. Keep the reference and output routing controlled so that switching or retriggering does not introduce unintended timing discontinuities.
Recommended
Test and Measurement Instrumentation
The ICS271PG can support test and measurement instruments that require multiple coherent clock outputs from a common reference. The combination of three PLLs, as many as six outputs, and programmable configuration reduces the number of separate oscillators needed when several converter or digital sections require related rates. CMOS outputs provide a straightforward interface to measurement and control electronics, and operation up to 200 MHz covers clocking needs for higher-speed sampling or processing sections. Validate output accuracy, jitter, loading, and startup behavior against the instrument’s measurement specification, particularly when calibration or reference switching is required.
Recommended
Industrial Control and Data Acquisition
The ICS271PG is useful in industrial control systems where a deterministic crystal reference must serve several digital subsystems. Up to six programmable outputs can support controller logic, data converters, communications interfaces, and peripheral timing from a common source. The triple-PLL architecture provides flexibility when different sections require related but nonidentical frequencies, and the CMOS outputs integrate with ordinary digital clock inputs. Designers should avoid treating nominal output frequency as the complete performance specification: assess startup sequencing, output jitter, clock-load behavior, and the tolerance of the complete timing chain before approving the architecture for industrial control equipment.
Recommended
Interface and Serialization Clocking
The ICS271PG can serve interface-heavy systems requiring a small set of precisely related clock outputs. A crystal-referenced source, three programmable PLLs, and up to six CMOS outputs allow the design to derive separate clocks for serializers, receivers, memory interfaces, or control logic without relying on a large collection of discrete oscillators. The maximum 200 MHz output provides useful flexibility for moderately high-speed digital interfaces. Correct implementation requires reviewing the device’s output-frequency limits, programmed divider ratios, and timing relationship among channels. Validate the complete interface eye and setup-and-hold requirements rather than checking clock frequency alone.
Recommended
Embedded System Timing Hub
The ICS271PG acts as a timing hub for embedded systems that need more than one clock domain but benefit from centralized programming. Its one clock-synthesis circuit, three PLLs, and as many as six outputs can support processor, peripheral, communications, and reference timing functions. Using a crystal input provides a recognizable reference point for system configuration, while PLL bypass creates a selectable operating mode that may assist validation. The design should compare the configured outputs with each receiving device’s clock requirements and confirm whether bypass transitions are acceptable. Maintain short, controlled clock routes and follow the recommended decoupling and reference-circuit layout.
Recommended
Engineering reference data for ICS271PG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ICS271PGILF | 271PGLF |
|---|---|---|---|
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Package | 20-pin TSSOP | 20-pin TSSOP | 20-pin TSSOP |
Key Differentiators
- Centralized programmable clock generation (vs ICS271PGILF)
- High-frequency output capability (vs 271PGLF)
- Flexible reference and synthesis modes (vs ICS271PGILF)
Design Notes
Route the crystal reference and clock outputs as controlled, short paths, and follow the manufacturer’s recommended component placement and grounding arrangement. Keep the reference oscillator loop compact and avoid routing it adjacent to high-current or high-speed switching nodes. Because the device can produce as many as six outputs, assign each output before layout to prevent unnecessary crossings and reduce coupling between unrelated clock domains.
Apply the manufacturer’s recommended supply decoupling directly at the power and ground pins, and account for the switching and harmonic content of every enabled CMOS output when planning the power budget. The ICS271PG can operate up to 200 MHz, so output count, load, and edge activity can materially affect current demand. Validate the configuration across startup, normal operation, and PLL-bypass transitions rather than checking only the steady-state clock condition.
Do not substitute a related suffix solely because the package designation appears identical. Confirm pin functions, configuration storage, electrical limits, temperature grade, and lifecycle status for the exact ordering code. Program all required frequencies and relationships together with VersaClock, then test each output and every planned bypass transition against the system timing budget before production release.
Treat clock outputs as active high-speed signals once output frequency and edge content are significant. Use controlled impedance routing where appropriate, minimize stubs and unnecessary loading, and verify amplitude, jitter, rise time, and crosstalk at the receiving device. The ICS271PG specification of 200 MHz maximum output frequency establishes capability, but each board layout must still be validated as a complete distribution network.
Compliance Information
The accessible component listings do not state the required environmental or material-compliance status. Confirm these attributes with the manufacturer before release to production.