Diodes Incorporated

PI7C9X7954BFDE - PCIe Quad UART Bridge 128-LQFP | Diodes Inc

N.º da peça: PI7C9X7954BFDE ✓ Ativo
Em estoque Enviado em 1 a 3 dias úteis
1.8 V Vdss 128-LQFP (14x14 mm) Package
Contato para preços
MOQ: 1 |
Preço atualizado: 2026-10-19
Preços por volume
Qtd. Preço unitário Total
1 $0 $0,00
10 $0 $0,00
100 $0 $0,00
500 $0 $0,00
1.000 $0 $0,00
ℹ️ Todos os preços estão em USD

PI7C9X7954BFDE Visão geral

The Diodes Incorporated PI7C9X7954BFDE is a PCI Express to Quad UART (Universal Asynchronous Receiver-Transmitter) I/O bridge delivered in a 128-pin LQFP (14x14 mm) package. It integrates a PCIe Gen1 x1 upstream link with four 16550-compatible UART channels, each with a 128-byte FIFO, and operates from 1.8V and 3.3V supply rails.

A PCIe-to-UART bridge is a serial interface controller that converts a PCI Express bus transaction into legacy-style asynchronous serial communication. In the system hierarchy, it sits between the interface controller family and the broader categories of communication ICs and bridge ICs, allowing modern PCIe-only CPU platforms to retain multi-channel RS-232/RS-485 serial ports without a legacy PCI bus.

Key features include four independent UART channels, 128-byte transmit and receive FIFOs per channel for reduced CPU interrupt overhead, a PCI Express x1 upstream interface, and dual 1.8V core / 3.3V I/O operation. The lead-free (Pb-free) construction and reduced 14x14 mm package size address modern system requirements for high performance and compact PCB footprints.

Architecturally, the device bridges PCIe configuration and memory-mapped transactions to the internal UART register set, maintaining 16550 register compatibility so standard OS serial drivers can operate the ports. The deep FIFOs decouple bursty processor access from slower serial line rates, improving throughput in multi-port systems.

Typical applications include remote access servers, industrial automation and process control, instrumentation, point-of-sale (POS) terminals, ATMs, and multi-port RS-232 cards.

Design consideration: verify the PCIe reference clock and reset sequencing against the manufacturer datasheet, and provide adequate decoupling on both 1.8V and 3.3V rails.

This page synthesizes distributor pricing context, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.

Alternativas drop-in para PI7C9X7954BFDE — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.

Variantes desta série

Modelos da mesma série compatíveis como drop-in com PI7C9X7954BFDE (mesmo formato e footprint) — diferindo em UART Compatibility, Function.

Diodes Incorporated
UART Compatibility: 16C550-type (software compatible)
Comparar com PI7C9X7954BFDE →
Diodes Incorporated
UART Compatibility: 16550-compatible with FIFO
Function: PCI Express x1 to 4-channel UART bridge
Comparar com PI7C9X7954BFDE →

Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:

PI7C9X7954AFDE

✅ Drop-In
📦 128-LQFP (14x14 mm)
different silicon revision/grade suffix in the same family; same PCIe Quad UART function, same footprint, pin-to-pin compatible per distributor comparison listings

📋 Alternativa de referência (fora do catálogo)

PI7C9X7954BFZE

✅ Drop-In ⚠️ Especificações não verificadas
📦 128-LQFP (14x14 mm)
same-family shipping-code variant of the identical BF silicon with different packing/order code; electrical performance identical per family datasheet

📋 Alternativa de referência (fora do catálogo)

PI7C9X7954BFDE Classificações máximas e características elétricas

Função PCI Express to Quad UART I/O Bridge
UART Channels 4
FIFO Size 128 byte per UART channel
Upstream Interface PCI Express x1
Supply Voltage (Core) 1.8 V
Supply Voltage (I/O) 3.3 V
Encapsulamento 128-LQFP (14x14 mm)
Tipo de montagem Surface Mount
UART Compatibility 16550-compatible register set
Lead-Free (Pb-Free) Yes
Status RoHS Compliant
Typical Applications Remote Access Servers, Automation, Process Control, Instrumentation, POS, ATM, Multi-port RS-232

Guia de Configuração de Pinos do PI7C9X7954BFDE 128-lqfp (14x14 mm)

Configuração de pinos para PI7C9X7954BFDE (pacote 128-lqfp (14x14 mm)). Este dispositivo de potência possui terminais de gate, drain e source. Para pacotes não polarizados, consulte o datasheet do fabricante para a orientação exata do pino 1 e detalhes do footprint. Aplicações comuns incluem projeto de fontes de alimentação, acionamento de motores e comutação de cargas.

Diagrama de pinagem do pacote 128-lqfp (14x14 mm) para PI7C9X7954BFDE

Nenhum dado detalhado de pinagem disponível para PI7C9X7954BFDE.

Consulte a ficha técnica para a configuração completa dos pinos.

Aplicações típicas

PI7C9X7954BFDE é adequado para 6 aplicaçãos: Remote Access Servers, Industrial Automation and Process Control, Point-of-Sale (POS) Terminals, ATM and Financial Kiosks, Instrumentation and Test Equipment, Multi-port RS-232 Add-in Cards.

🖥️

Remote Access Servers

Remote access servers concentrate dozens of dial-up, console, and management serial lines behind one host. The PI7C9X7954BFDE fits this role because its PCIe x1 upstream link attaches directly to modern server chipsets that no longer offer legacy PCI or ISA buses, while its four 16550-compatible UARTs with 128-byte FIFOs sustain buffered line rates without flooding the CPU with interrupts. Each channel is driver-compatible with standard operating system serial stacks, so console-management software works unchanged. Placed on a multi-port adapter card, one bridge serves four ports and multiple bridges can be cascaded across PCIe lanes, scaling port density. The main trade-off versus PCIe switch plus discrete UARTs is integration: fewer parts, smaller board area, but port count fixed at four per device.

🏭

Industrial Automation and Process Control

Factory automation and process-control equipment still communicates with PLCs, drives, meters, and sensors over RS-232 and RS-485 serial links. The PI7C9X7954BFDE suits these systems because it bridges a PCI Express host (industrial PC or edge controller) to four legacy UART channels with 16550 register compatibility, letting existing control software run unmodified. The 128-byte FIFOs absorb burst transfers during polling cycles of multiple field devices, and the 3.3 V I/O rail interfaces cleanly to standard RS-485 transceivers. According to the manufacturer product description, automation and process control are explicitly listed target applications. Designers should verify the operating temperature range in the datasheet for cabinet environments and provide isolation between the UART lines and field wiring via the transceiver stage.

🧾

Point-of-Sale (POS) Terminals

Retail POS terminals connect receipt printers, barcode scanners, card readers, and cash drawers that frequently expose RS-232 serial interfaces. The PI7C9X7954BFDE fits because a single PCIe x1 link from the terminal's x86 or ARM host yields four independent COM ports, each with a 16550-compatible register set that standard POS application software addresses without custom drivers. The 128-byte FIFOs smooth bursty printer data streams, and the 14x14 mm 128-LQFP package keeps the adapter area small inside compact terminal enclosures. POS and ATM are named applications in the manufacturer product description. Design considerations include ESD protection on all externally accessible serial lines, since retail environments subject connectors to frequent human contact and cable swaps.

🏧

ATM and Financial Kiosks

ATMs and financial kiosks interface to encrypting PIN pads, receipt printers, currency modules, and modems over serial ports managed by a modern PCIe host. The PI7C9X7954BFDE addresses this need directly: the manufacturer product description names ATM as a target application, and the bridge's 16550 compatibility preserves the legacy serial driver model that kiosk software stacks rely on. Four channels with 128-byte FIFOs handle concurrent peripheral traffic without host intervention between transactions. The dual 1.8 V core and 3.3 V I/O operation supports low-power standby states required by energy regulations for always-on kiosks. Hardware designers should implement the PCIe reset and clock sequencing exactly as specified in the datasheet and protect each external serial port with robust ESD and surge clamping for unattended public environments.

🔧

Instrumentation and Test Equipment

Bench and rack instrumentation frequently retains RS-232 command interfaces defined by legacy SCPI-style protocols. The PI7C9X7954BFDE lets an instrument's PCIe-based controller board drive four such serial devices - or expose four external ports - with guaranteed register-level compatibility, since the four UART channels implement the standard 16550 register set. The 128-byte FIFOs maintain data integrity during long ASCII transaction sequences at moderate baud rates, and the PCIe enumeration presents each port as a standard COM device to host software. Instrumentation is explicitly listed among the manufacturer's target applications. Because measurement timing can be sensitive, designers should validate the UART clock source tolerance specified in the datasheet and budget interrupt latency for simultaneous activity on all four channels in high-throughput test sequences.

🔌

Multi-port RS-232 Add-in Cards

The classic use case for this device is a PCI Express add-in card providing four RS-232 COM ports for servers, thin clients, and embedded PCs. The PI7C9X7954BFDE is purpose-built for this: PCIe x1 upstream, four 16550-compatible UARTs, 128-byte FIFOs per channel, and a 128-LQFP (14x14 mm) package that fits a half-height card layout with room for four line transceivers and DB-9 connectors. Multi-port RS-232 is a named application in the manufacturer product description. Compared to stacking two dual-UART USB bridges, a single bridge IC reduces BOM count and firmware complexity, and enumeration is deterministic at boot - important for port-name stability in server management software. Verify the maximum UART baud rate and clock configuration options in the datasheet against your target line speeds.

Resumo dos produtos recomendados

MAX3232E RS-232 line transceiver for UART ports Usado em: Remote Access Servers, Point-of-Sale (POS) Terminals MAX3243E Multi-channel RS-232 transceiver Usado em: Remote Access Servers, Multi-port RS-232 Add-in Cards MAX3485 RS-485 transceiver for UART channel Usado em: Industrial Automation and Process Control SN65HVD3082E Half-duplex RS-485 transceiver Usado em: Industrial Automation and Process Control SP3010 ESD protection for serial line Usado em: Point-of-Sale (POS) Terminals MAX3237E High-speed RS-232 transceiver Usado em: ATM and Financial Kiosks TPD4E05U06 ESD protection array for UART lines Usado em: ATM and Financial Kiosks MAX3222E RS-232 transceiver for instrument ports Usado em: Instrumentation and Test Equipment SN65HVD75 RS-485 transceiver for long cable runs Usado em: Instrumentation and Test Equipment SP3232E Dual RS-232 transceiver Usado em: Multi-port RS-232 Add-in Cards
What is the PI7C9X7954BFDE?
The PI7C9X7954BFDE is a PCI Express to Quad UART I/O bridge from Diodes Incorporated. It provides a PCI Express x1 upstream link and four independent 16550-compatible UART channels, each with a 128-byte FIFO, in a 128-pin LQFP (14x14 mm) package. According to the manufacturer product description, it is designed for high performance, lead-free systems used in remote access servers, automation, process control, instrumentation, POS, ATM, and multi-port RS-232 applications.
How many UART channels does the PI7C9X7954BFDE have?
The PI7C9X7954BFDE provides four independent UART (Universal Asynchronous Receiver-Transmitter) channels behind a single PCI Express x1 bridge. Each channel has a 128-byte FIFO, which reduces processor interrupt load compared to byte-oriented 16550 UARTs. This makes the part well suited to multi-port serial cards where four RS-232 or RS-485 ports must be driven from one PCIe slot without a legacy PCI bus.
What is the FIFO size of the PI7C9X7954BFDE UARTs?
Each of the four UART channels in the PI7C9X7954BFDE integrates a 128-byte FIFO for both transmit and receive directions, per distributor listings (Arrow: UART 4-CH 128byte FIFO). The 128-byte depth is four times larger than the 16-byte FIFO of classic 16550A UARTs, allowing larger burst transfers over PCIe and fewer CPU interrupts at high serial line rates.
What supply voltages does the PI7C9X7954BFDE require?
The PI7C9X7954BFDE operates from dual supply rails: 1.8 V for the core logic and 3.3 V for the I/O and PCIe interface, as listed by distributors (Arrow: 1.8V/3.3V, 128-Pin LQFP). Designers must sequence or verify both rails per the manufacturer datasheet and decouple each supply pin pair with local ceramic capacitors to maintain PCIe signal integrity and UART timing accuracy.
What package does the PI7C9X7954BFDE come in?
The PI7C9X7954BFDE is housed in a 128-pin LQFP (Low-Profile Quad Flat Package) with a 14x14 mm body, per DigiKey and FindIC listings (also described as 128-Pin LFQFP). This surface-mount package supports compact multi-port serial designs and is lead (Pb)-free, meeting the reduced package size and RoHS-oriented requirements stated in the manufacturer product description.
What are the key specifications of the PI7C9X7954BFDE engineers should know?
Key specifications: a PCI Express x1 upstream bridge, four 16550-compatible UART channels, 128-byte FIFOs per channel, dual 1.8 V core and 3.3 V I/O supplies, and a 128-pin LQFP (14x14 mm) lead-free package. According to the Diodes Incorporated product description, the PI7C9X7954 targets remote access servers, automation, process control, instrumentation, POS, ATM, and multi-port RS-232 systems requiring modern PCIe host connectivity.
What is the difference between PI7C9X7954BFDE and PI7C9X7954AFDE?
The PI7C9X7954BFDE and PI7C9X7954AFDE are both Diodes Incorporated (Pericom heritage) PCI Express Quad UART bridges in the same 128-pin LQFP package; the letter code identifies a different silicon revision or grade. Distributor comparison listings (Avaq) treat them as closely matched variants. Engineers should confirm the revision-specific errata and electrical differences in the manufacturer datasheet before substituting one for the other, since both share the same footprint and pinout.
What is the best drop-in replacement for PI7C9X7954BFDE?
The closest drop-in replacement is the same-family PI7C9X7954AFDE from Diodes Incorporated, which shares the 128-LQFP (14x14 mm) footprint and the PCIe-to-Quad-UART function. No cross-brand pin-compatible equivalents were found in the available cross-reference data, which is typical for specialized PCIe-to-UART bridges. Before replacement, verify the suffix-code differences (silicon revision, electrical grade) against the manufacturer datasheet and qualification requirements of your design.
Can PI7C9X7954BFDE replace PI7C9X7954AFDE?
Yes, in most designs the PI7C9X7954BFDE can replace the PI7C9X7954AFDE because both are members of the PI7C9X7954 PCI Express Quad UART bridge family in the identical 128-LQFP (14x14 mm) package with the same pinout. According to distributor comparison data (Avaq), the two are specification-comparable variants. Confirm the revision letter implications - firmware, errata, and timing margins - with the Diodes Incorporated datasheet before committing the swap in production.
Is there a cross-brand equivalent for the PI7C9X7954BFDE?
No verified cross-brand pin-compatible equivalent for the PI7C9X7954BFDE was found in available manufacturer or distributor cross-reference data. PCIe-to-multi-channel-UART bridges with 128-byte FIFOs are a niche function largely served by the Diodes Incorporated (Pericom) PI7C9X795x family. Engineers needing a second source should evaluate functional alternatives such as PCIe-to-multi-UART solutions from other vendors, but these require PCB redesign rather than drop-in substitution.
When should I choose the PI7C9X7954BFDE over a discrete quad UART solution?
Choose the PI7C9X7954BFDE when a modern PCIe-only host platform must expose four legacy serial ports without a PCI bus. Compared to a PCIe switch plus four discrete UARTs, it integrates the bridge and the UARTs in one 128-LQFP device, saving board area, BOM lines, and PCIe lanes. Compared to USB-to-serial solutions, it provides deterministic PCIe enumeration and standard OS serial drivers. Discrete or USB approaches suit designs needing only one or two ports.
Is the PI7C9X7954BFDE suitable for industrial automation and POS applications?
Yes. According to the Diodes Incorporated product description, the PI7C9X7954 family is explicitly designed for automation, process control, instrumentation, POS, ATM, remote access servers, and multi-port RS-232 applications. Its 16550-compatible register set works with standard serial drivers, and the 128-byte FIFOs handle buffered communication at typical industrial line rates. Designers should verify the operating temperature range and any required conformance qualifications for their specific industrial environment in the datasheet.
Where can I buy PI7C9X7954BFDE and what is the price?
The PI7C9X7954BFDE is listed at major distributors including DigiKey (ships today per its listing), Mouser, Arrow, and via aggregators Octopart and DigiPart, which compare bulk discounts from 5 distributors. Exact unit pricing varies by quantity and stock; as of 2026-10-20, consult the distributor listings for live pricing and availability. On XAIPART, submit an RFQ for volume pricing on this part.
Is the PI7C9X7954BFDE in stock and what is the lead time?
DigiKey's listing for the PI7C9X7954BFDE states "Buy now, ships today", indicating distributor stock exists as of the data retrieval date (2026-10-20). Mouser, Arrow, and additional brokers listed on Octopart also carry the part. Lead times for in-stock distributor product are typically a few business days; for production volumes beyond distributor stock, request a quotation since factory lead times can extend to several weeks depending on Diodes Incorporated scheduling.
Where can I download the PI7C9X7954BFDE datasheet PDF and find its pinout?
The official PI7C9X7954 datasheet is available from the Diodes Incorporated product page at diodes.com/part/view/PI7C9X7954, and a PDF copy is also hosted on Mouser's catalog site. The 128-LQFP pinout, register map, and PCIe interface details are documented in the manufacturer datasheet; distributor pages (DigiKey, FindIC, Jotrin) also provide datasheet download links. Always use the manufacturer's latest revision for pinout and electrical design work.
Is the PI7C9X7954BFDE RoHS compliant and lead-free?
Yes. According to the Diodes Incorporated product description, the PI7C9X7954 is specifically designed to meet "the latest system requirements of high performance, lead (Pb)-free" systems, and the BF suffix denotes the lead-free RoHS-compliant version. The 128-pin LQFP package is manufactured without lead-based finishes. For formal REACH, halogen-free, and conflict-minerals declarations, request the latest compliance certificates from Diodes Incorporated or your distributor, as those documents are updated independently of the datasheet.
Does the PI7C9X7954BFDE work with standard operating system serial drivers?
Yes. The PI7C9X7954BFDE implements a 16550-compatible UART register set behind the PCI Express bridge, which is the de facto standard that legacy serial drivers in Windows, Linux, and RTOS environments expect. According to the manufacturer's product description, this compatibility is a core design goal of the family. In practice, the four ports enumerate as standard PCIe-connected serial COM ports without vendor-specific drivers on mainstream platforms, simplifying integration into POS, ATM, and automation systems.

Dados de referência de engenharia para PI7C9X7954BFDE — comparação, orientação de projeto e informações de conformidade.

Guia de seleção

Choose the PI7C9X7954BFDE when a PCIe-only host platform needs four legacy serial ports with standard 16550 driver compatibility in a single bridge IC - typical for remote access servers, POS/ATM terminals, instrumentation, and multi-port RS-232 add-in cards. Within the family, choose between the BFDE and the PI7C9X7954AFDE based on silicon revision: both are pin-compatible in the same 128-LQFP (14x14 mm) package, so check revision errata notes and current availability, then standardize on one suffix. No verified cross-brand drop-in equivalent exists, so designs requiring a second source must plan for PCB redesign or accept functional alternatives (PCIe switch plus discrete UARTs, or USB-to-serial hubs) with their larger BOM and footprint. For one- or two-port designs, a simpler PCIe-to-single/dual-UART device may reduce cost; the 7954 wins on per-port integration density at four ports.

Comparação com alternativas

Parâmetro Este produto PI7C9X7954AFDE PI7C9X7954BFZE
Package 128-LQFP (14x14 mm) 128-LQFP (14x14 mm) - same 128-LQFP (14x14 mm) - same
Brand Diodes Incorporated Diodes Incorporated Diodes Incorporated
UART Channels 4 4 4
FIFO Size per Channel 128 byte 128 byte 128 byte
Upstream Interface PCI Express x1 PCI Express x1 PCI Express x1
Supply Voltages 1.8 V / 3.3 V 1.8 V / 3.3 V 1.8 V / 3.3 V
UART Register Compatibility 16550-compatible 16550-compatible 16550-compatible
Lead-Free / RoHS Yes / Compliant Yes / Compliant Yes / Compliant

Principais diferenciais

  • Integrated PCIe bridge + four UARTs in one package (vs PI7C9X7954AFDE)
  • 128-byte FIFOs per channel (vs PI7C9X7954AFDE)
  • Compact 14x14 mm 128-LQFP lead-free package (vs PI7C9X7954AFDE)

Notas de projeto

The PI7C9X7954BFDE requires dual rails: 1.8 V for core logic and 3.3 V for I/O and the PCIe interface (per distributor listings). Place 100 nF ceramic decoupling capacitors at each supply pin pair plus bulk 10 uF per rail. Verify power-rail sequencing requirements in the manufacturer datasheet - violating core/I/O sequencing order can back-power the device through internal ESD structures and cause reliability issues. Estimated: total power dissipation is low for bridge devices of this class, but confirm the datasheet typical/max current figures for your clock configuration before finalizing the regulator budget.

The PCIe x1 differential pair (PETp/n, PERp/n) should follow standard PCIe layout rules: 100 ohm differential impedance, length matching within 5 mils between the pair, no stubs, and AC coupling capacitors (typically 75-100 nF, per PCIe CEM/base spec values - confirm exact values for your form factor) placed near the transmitter side. Keep the pair away from the UART switching lines to minimize crosstalk. Reference the manufacturer datasheet layout section for the reference clock input requirements, since incorrect clock levels are the most common cause of link-training failures with bridge ICs.

When substituting the same-family PI7C9X7954AFDE for the BFDE, verify the suffix code's silicon revision implications in the manufacturer documentation - revision errata can affect PCIe link training behavior or UART timing edge cases even on pin-compatible parts. Also confirm reset timing: PERST# must be asserted long enough relative to power-good and the 100 MHz reference clock, per the datasheet power-up sequence. Skipping this verification is the most frequent source of field failures when second-sourcing PCIe bridge silicon.

Informações de conformidade

RoHS
Compliant
REACH
Unknown
AEC-Q100
Not Applicable
Sem chumbo
Yes
Sem halogênios
Unknown
Minerais de conflito
Unknown

Manufacturer product description states the PI7C9X7954 is designed to meet latest system requirements of high performance and lead (Pb)-free construction. REACH, halogen-free, and conflict-minerals declarations were not found in the provided data.

Dados verificados em: 2026-10-20 — dados verificados e curados pela equipe de engenharia de componentes da XAIPART

Buscas relacionadas

PI7C9X7954BFDE PI7C9X7954BFDE datasheet Diodes Incorporated PI7C9X7954BFDE PCIe quad UART bridge 128 LQFP PI7C9X7954BFDE vs PI7C9X7954AFDE PI7C9X7954BFDE drop-in replacement PCI express to 4 port RS-232 bridge IC PI7C9X7954BFDE price buy PI7C9X7954BFDE equivalent substitute PI7C9X7954 pinout 128-pin LQFP PCIe UART bridge for POS ATM terminal 16550 compatible UART PCIe controller

Componentes & termos relacionados

Diodes Incorporated PI7C9X7954BFDE PI7C9X7954 PI7C9X7954AFDE Pericom PCI Express PCIe x1 bridge UART Universal Asynchronous Receiver-Transmitter 16550-compatible UART 128-byte FIFO LQFP 128-LQFP (14x14 mm) RoHS Pb-free RS-232 RS-485 remote access server point-of-sale (POS) ATM industrial automation process control instrumentation interface bridge IC
RFQ de cotação rápida
Preencha todos os detalhes — nossa equipe de vendas responderá em até 24 horas
Part number Fabricante Encapsulamento QTY Preço-alvo Total
Total: $0.00 USD
✓
Cotação enviada!

Responderemos seu e-mail em até 24 horas

1
RFQ enviada
2
Cotação recebida
3
Pedido realizado
4
Pagamento
5
Enviado
6
Entregue
Ver detalhes da RFQ