ICS281PG - 200 MHz Triple-PLL Clock Synthesizer | Renesas
N.º da peça: ICS281PG ✓ AtivoICS281PG Visão geral
A clock synthesizer generates stable timing signals from a lower-frequency reference and, in this case, uses three phase-locked loops to produce multiple high-frequency outputs. The PLL-based approach belongs to the clock and timing IC hierarchy, where frequency synthesis supports processor clocks, communications infrastructure, storage interfaces, and other digital systems requiring controlled clock distribution.
The principal feature is the combination of triple-PLL architecture, field programmability, and spread-spectrum clock generation. Bypass operation gives the design team a way to move between the synthesized and reference-clock paths, while CMOS output signaling supports integration with compatible digital logic. The 200 MHz maximum frequency makes the device suitable for clock trees operating below that limit.
The ICS281 family provides up to three clock outputs, including multiple reference clocks according to the manufacturer documentation. The 1:3 ratio identifies a supported clock-generation relationship, while field programming allows configuration through the device's programming interface. These features make the ICS281PG more versatile than a fixed-frequency oscillator for systems that require programmable timing and controlled spectral spreading.
Typical applications include communications equipment, network interface clock trees, high-speed digital processing systems, storage controllers, and clock-generation blocks in industrial equipment. Spread-spectrum operation can reduce narrowband emissions, making the device useful when electromagnetic compatibility is important. Designers must still verify each output's frequency, jitter, duty-cycle, and modulation limits against the target system requirements.
The principal design consideration is preserving clean, low-jitter reference distribution to every PLL. Use the recommended reference and loop-filter network from the manufacturer datasheet, keep clock traces short, and provide solid return paths beneath high-speed signals. Decoupling should be placed close to supply pins, while output buffering or additional clock drivers may be needed for fanout beyond the device's intended loading.
This page consolidates the documented 200 MHz frequency capability, triple-PLL architecture, programming features, package data, sourcing guidance, and practical clock-tree considerations. It also distinguishes confirmed drop-in candidates from lower-confidence engineering options so that schematic and PCB decisions can be checked before production release.
Alternativas drop-in para ICS281PG — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
281PGLF
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
ICS281
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
ICS280
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
ICS282
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
ICS289
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
ICS281PG Especificações
| Product Type | Clock/Frequency Synthesizer IC |
| Architecture | Triple PLL |
| Maximum Output Frequency | 200 MHz |
| Number of Circuits | 1 |
| Input Type | Clock or crystal |
| Tipo de saída | CMOS |
| PLL Bypass | Yes |
| Input-to-Output Ratio | 1:3 |
| Programming Method | Field programmable |
| Clock Modulation | Spread spectrum |
| Output Count | Up to 3 |
| Encapsulamento | 16-TSSOP |
| Package Width | 4.40 mm |
| Package Length | 0.173 inch |
| Tipo de montagem | Surface mount |
Guia de Configuração de Pinos do ICS281PG 0.173 inch
Configuração de pinos para ICS281PG (pacote 0.173 inch). A numeração dos pinos, funções e diagramas de conexão estão definidos no datasheet do fabricante. Consulte-o para o footprint exato e diretrizes de soldagem.
Nenhum dado detalhado de pinagem disponível para ICS281PG.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
ICS281PG é adequado para 6 aplicaçãos: Network Interface Clock Tree, Communications Equipment Timing, Processor and FPGA Clock Distribution, Storage Controller Clocking, Industrial Control and Instrumentation, High-Speed Digital Test Equipment.
Network Interface Clock Tree
The ICS281PG fits network-interface clock trees that need several related CMOS clocks derived from one stable reference. Its triple-PLL architecture can generate up to three outputs, while the documented 200 MHz maximum frequency covers many digital interface clock domains. Field programming allows divider and frequency relationships to be adjusted without changing the oscillator itself. The design must still verify the required output frequency, jitter, duty cycle, load, and spread-spectrum profile for each network interface, and it must preserve a low-noise reference to avoid degrading all three clock paths.
Communications Equipment Timing
Communications equipment benefits from programmable clock synthesis when multiple transceiver, controller, and data-conversion domains require coherent timing. The ICS281PG accepts a clock or crystal reference and uses three PLLs to produce up to three high-quality outputs, reducing the number of separate frequency-generation blocks needed. Its spread-spectrum capability can also spread narrowband clock energy to support EMC design goals. Engineers should select the reference frequency and programming mode from the manufacturer limits, then confirm jitter and modulation values against the communications system's mask and regulatory requirements.
Processor and FPGA Clock Distribution
The ICS281PG can provide programmable clocks for processor, FPGA, and other high-speed digital subsystems that need more than one derived timing signal. A 200 MHz maximum output frequency, CMOS outputs, and programmable divider relationships suit designs where the same reference must feed multiple clock domains. Use the device close to the clock-distribution point, provide a clean reference, and minimize stub branches to control edge degradation and skew. The exact fanout and operating frequency must remain within the datasheet's load, jitter, and output-slew specifications.
Storage Controller Clocking
Storage controllers and their attached interface logic can benefit from the ICS281PG's field-programmable triple-PLL architecture. The device can derive multiple related clock outputs from one reference while supporting spread-spectrum operation for systems that need reduced narrowband emissions. Its 16-TSSOP package also supports compact PCB layouts where component area is constrained. Validation should include the controller's required clock frequency, source-synchronous timing margin, jitter tolerance, and the relationship between reference and output clocks during startup, bypass, and reprogramming transitions.
Industrial Control and Instrumentation
Industrial control and instrumentation systems can use the ICS281PG to organize several digital clock domains around a common reference. Programmable PLL ratios make the device adaptable to different controller, converter, and communication-clock requirements, while the CMOS outputs support conventional digital logic connections. Spread-spectrum operation may assist with conducted or radiated-emission control when the programmed profile satisfies the applicable equipment standard. Confirm operating-temperature limits, supply tolerances, clock jitter, and EMC performance in the final industrial equipment design.
High-Speed Digital Test Equipment
The ICS281PG is appropriate for clock-generation sections of high-speed digital test equipment where programmable frequencies and multiple outputs simplify synchronization across channels. Its triple-PLL design and field programmability allow a reference source to be converted into several required timing signals, and bypass mode supports controlled reference routing during setup or diagnostic sequences. Engineers should verify phase relationships, output-to-output skew, deterministic jitter, and the effect of spread-spectrum modulation before using the clock as a precision measurement reference.
Dados de referência de engenharia para ICS281PG — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | 281PGLF | ICS281 | ICS280 | ICS282 | ICS289 |
|---|---|---|---|---|---|---|
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Package | 16-TSSOP, 4.40 mm width | 16-TSSOP | 16-TSSOP | 16-TSSOP | 16-TSSOP | 16-TSSOP |
Principais diferenciais
- Provides three programmable PLL paths in one clock synthesizer (vs 281PGLF)
- Supports programmable spread-spectrum clock generation (vs ICS280)
- Combines PLL synthesis with a bypass path (vs ICS282)
Notas de projeto
Treat the reference clock as the foundation of all three PLL outputs. Route it over a continuous reference plane, avoid split planes and long stubs, and place termination at the correct end of the transmission line. Because phase noise and reference jitter propagate into the synthesized outputs, a clean reference can improve output timing more effectively than adding filtering after the clock has already accumulated noise.
Place the ICS281PG close to the branches that consume its clocks and keep the traces short and matched where output-to-output skew matters. Use a solid ground reference beneath every clock trace, avoid vias where practical, and do not create unterminated test pads on sensitive nodes. If a clock must fan out to distant circuits, use an appropriate clock-buffer stage rather than relying on long PCB branches.
Place the required bypass capacitors at the device supply pins with very short ground returns, following the manufacturer datasheet's recommended network. Keep switching-converter routing and clock outputs spatially separated to reduce supply-induced jitter. Validate startup and bypass transitions because changing between PLL and reference-clock paths can alter the relationship among the three outputs.
Do not select a clock synthesizer from maximum frequency alone. Verify the supported reference range, programmed divider ratios, output count, bypass behavior, jitter, duty-cycle limits, load capability, and spread-spectrum profile for the intended configuration. Before substituting an ICS28x-family device, compare its complete pin table and programming procedure with the ICS281PG even when both use a 16-TSSOP outline.
Informações de conformidade
No definitive environmental, automotive, lead-free, halogen-free, or conflict-minerals declarations were included in the product information. The 'L' suffix in 281PGLF must not be treated as proof of a specific compliance declaration without the relevant manufacturer labeling document.