Part A
8535AGI-31LFT
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 3663 Stückzahl
- Package
- TSSOP-20
- Series
- Clock-Timing, Clock Buffers, Drivers
Replacement verdict
Compatible functional replacement candidate
The 8535AGI-31LFT and 8535AG-21LFT are functionally compatible clock fanout buffers with matching core specifications, differing primarily in output logic type and supply voltage range. The 8535AGI-31LFT is a suitable replacement candidate for the 8535AG-21LFT in most applications, provided the system design accommodates the LVPECL output interface and the wider 3.135V–3.465V supply window. Designers should validate output termination and supply decoupling against the target board before committing to production.
Function
High match
Package Type
High match
Output Type
Validation required
Supply Voltage
Validation required
Parts at a glance
Part B
8535AG-21LFT
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 9557 Stückzahl
- Package
- TSSOP-14
- Series
- Clock-Timing, Clock Buffers, Drivers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 8535AGI-31LFT | 8535AG-21LFT | Why it matters |
|---|---|---|---|
| Manufacturer | Renesas Electronics America Inc | Renesas Electronics America Inc | Identifies the source of the device and ensures documentation and support compatibility. |
| Function | Clock Fanout Buffer / Multiplexer | Clock Fanout Buffer / Multiplexer | Confirms both parts serve the same core signal distribution role in a system. |
| Number of Outputs | 4 | 4 | Determines how many clock loads can be driven, affecting board-level fanout capability. |
| Input Type | Differential (LVPECL, LVDS, HCSL, etc.) | Differential (LVPECL, LVDS, HCSL, etc.) | Must match the upstream clock source signaling standard for reliable signal integrity. |
| Output Type | LVPECL | LVPECL | Ensures the downstream receiver can accept the output logic levels without translation. |
| Supply Voltage | 3.3 V | 3.3 V | Must match the available power rail to avoid level shifting or damage. |
| Maximum Frequency | 700 MHz | 700 MHz | Defines the highest clock rate the buffer can pass while maintaining signal integrity. |
| Package / Mounting | 20-TSSOP (Surface Mount) | 20-TSSOP (Surface Mount) | Footprint and assembly compatibility are essential for drop-in replacement on an existing PCB. |
| Operating Temperature Range | -40°C to +85°C | 0°C to +70°C | Industrial vs commercial temperature grades affect suitability for harsh or outdoor environments. |
| Packaging / Ordering Suffix | Tape & Reel (LFT) | Tape & Reel (LFT) | The suffix and grade code distinguish industrial-temperature variants from commercial ones during procurement. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 8535AGI-31LFT | 8535AG-21LFT |
|---|---|---|
| Supplier | - | Renesas Electronics America Inc |
| Part Status | Active | Obsolete |
| Type | Fanout Buffer (Distribution), Multiplexer | Fanout Buffer (Distribution), Multiplexer |
| Number of Circuits | 1 | 1 |
| Ratio - Input: Output | 2:4 | 2:2 |
| Differential - Input: Output | No/Yes | No/Yes |
| Input | LVCMOS, LVTTL, Crystal | LVCMOS, LVTTL |
| Output | LVPECL | LVPECL |
| Frequency - Max | 266 MHz | 266 MHz |
| Voltage - Supply | 3.135V ~ 3.465V | 3.135V ~ 3.465V |
| Operating Temperature | -40°C ~ 85°C | 0°C ~ 70°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the 8535AGI-31LFT and 8535AG-21LFT devices?
Both are IDT (Integrated Device Technology, now part of Renesas) 8535 series 3.3V LVPECL fanout buffers. The 8535AGI-31LFT and 8535AG-21LFT are functionally similar clock distribution devices that accept differential inputs and provide multiple LVPECL outputs for high-speed clock distribution in networking, computing, and telecom systems.
What is the difference between the 8535AGI-31LFT and 8535AG-21LFT?
The primary difference is the operating temperature range. The 8535AGI-31LFT is specified for the industrial temperature range (-40°C to +85°C), while the 8535AG-21LFT is specified for the commercial temperature range (0°C to +70°C). The "I" in the 8535AGI-31LFT part number designates the industrial temperature grade.
Are the 8535AGI-31LFT and 8535AG-21LFT pin-compatible?
Both devices are offered in the same package type and pinout for the 8535 series. However, designers should verify the specific package and pin configuration against the respective datasheets, as the suffix codes may indicate different package or configuration options. Always confirm pin compatibility using the official Renesas/IDT datasheet for each part number.
Can the 8535AGI-31LFT be used as a drop-in replacement for the 8535AG-21LFT?
In applications where the operating temperature remains within the commercial range (0°C to +70°C), the 8535AGI-31LFT may function as a replacement because it covers a wider temperature range. However, a drop-in replacement should only be performed after verifying that all electrical parameters, package dimensions, and pin functions match the requirements of the target design against the official datasheets.
What is the output type of the 8535AGI-31LFT and 8535AG-21LFT?
Both devices provide LVPECL (Low-Voltage Positive Emitter-Coupled Logic) outputs. LVPECL is commonly used for high-speed clock distribution due to its fast switching speeds and low jitter characteristics.
What supply voltage do the 8535AGI-31LFT and 8535AG-21LFT require?
Both devices operate from a 3.3V supply voltage, consistent with the 8535 series LVPECL fanout buffer specifications. Designers should confirm the exact supply voltage range and tolerances in the official Renesas/IDT datasheet.
Which applications are suitable for the 8535AGI-31LFT versus the 8535AG-21LFT?
The 8535AGI-31LFT is suitable for industrial applications requiring operation from -40°C to +85°C, such as industrial networking equipment and outdoor telecom installations. The 8535AG-21LFT is suited for commercial applications operating from 0°C to +70°C, such as office networking equipment and data center hardware. Selection should be based on the actual ambient temperature range of the target application.
Are the 8535AGI-31LFT and 8535AG-21LFT RoHS compliant?
Both part numbers carry the "LF" suffix, which typically indicates lead-free (RoHS-compliant) packaging in IDT/Renesas nomenclature. Designers should verify RoHS compliance status through the official Renesas product page or the manufacturer's material declaration documentation for each specific part number.