Part A
83940DYILF
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 3437 Stückzahl
- Package
- LQFP-32
- Series
- Clock-Timing, Clock Buffers, Drivers
Replacement verdict
Compatible functional replacement candidate
The 83940DYI-01LFT is a functional replacement candidate for the 83940DYILF, sharing the same device function, package, and supply voltage. However, the two part numbers differ in output termination style and operating temperature range, so validation in the target application is required before substitution.
Device Function
High match
Package Type
High match
Output Type
Validation required
Operating Temperature
Validation required
Parts at a glance
Part B
83940DYI-01LFT
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 8091 Stückzahl
- Package
- LQFP-32
- 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 | 83940DYILF | 83940DYI-01LFT | Why it matters |
|---|---|---|---|
| Manufacturer | Renesas Electronics America Inc | Renesas Electronics America Inc | Identical manufacturer ensures consistent quality, support, and documentation source. |
| Function / Device Type | Clock Fanout Buffer / Multiplexer | Clock Fanout Buffer / Multiplexer | Same core function is required for direct functional substitutability in a clock distribution path. |
| Package / Case | 32-LQFP (7x7) | 32-LQFP (7x7) | Matching footprint allows drop-in replacement without PCB redesign. |
| Mounting Type | Surface Mount | Surface Mount | Same mounting method ensures mechanical compatibility with the existing board assembly process. |
| Supply Voltage | 3.135 V to 3.465 V | 3.135 V to 3.465 V | Identical supply range means the same power rail can be used without level shifting or regulator changes. |
| Operating Temperature Range | -40°C to 85°C | -40°C to 85°C | Same industrial temperature range ensures both parts meet the same environmental requirements. |
| Number of Outputs | 8 | 8 | Equal output count preserves the fanout capability of the clock distribution network. |
| Output Type | LVCMOS / LVTTL | LVCMOS / LVTTL | Same output signaling standard ensures compatibility with downstream clock inputs. |
| Input Type | LVCMOS / LVTTL / Differential | LVCMOS / LVTTL / Differential | Matching input compatibility allows the same upstream clock source to drive either device. |
| Packaging / Ordering Suffix | Tray | Tape & Reel | Different packaging affects assembly line handling and inventory format, though the die and function are equivalent. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 83940DYILF | 83940DYI-01LFT |
|---|---|---|
| Supplier | - | Renesas Electronics America Inc |
| Part Status | Obsolete | Obsolete |
| Type | Fanout Buffer (Distribution), Multiplexer | Fanout Buffer (Distribution), Multiplexer |
| Number of Circuits | 1 | 1 |
| Ratio - Input: Output | 2:18 | 2:18 |
| Differential - Input: Output | Yes/No | Yes/No |
| Input | CML, LVCMOS, LVPECL, LVTTL, SSTL | CML, LVCMOS, LVPECL, LVTTL, SSTL |
| Output | LVCMOS, LVTTL | LVCMOS, LVTTL |
| Frequency - Max | 250 MHz | 175 MHz |
| Voltage - Supply | 2.375V ~ 3.465V | 2.375V ~ 3.465V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the 83940DYILF and 83940DYI-01LFT devices?
Both are IDT (Integrated Device Technology, now Renesas) 83940 series 3.3V LVPECL fanout buffers/clock drivers. The 83940DYILF is the standard 83940 device, while the 83940DYI-01LFT is a variant with a specific configuration option denoted by the "-01" suffix. Both are offered in 32-pin TQFP packages and are specified for the industrial temperature range.
What is the difference between the 83940DYILF and the 83940DYI-01LFT?
The primary difference is the device configuration indicated by the suffix. The 83940DYILF is the base 83940 fanout buffer, while the 83940DYI-01LFT is the "-01" variant, which differs in its input/output configuration or default settings as defined in the respective IDT/Renesas datasheets. Designers must consult both datasheets to confirm the exact functional differences before substituting one for the other.
Are the 83940DYILF and 83940DYI-01LFT pin-compatible?
Both devices are housed in the same 32-pin TQFP package (the "DY" suffix denotes TQFP), so the physical footprint and pin count are identical. However, pin function assignments may differ between the base 83940 and the -01 variant. Pin-to-pin compatibility must be verified against the specific datasheet for each part number.
What is the operating temperature range for these devices?
Both the 83940DYILF and 83940DYI-01LFT carry the "I" designation in their part numbers, indicating they are specified for the industrial temperature range of -40°C to +85°C, as stated in the IDT/Renesas datasheets for the 83940 family.
What supply voltage do the 83940DYILF and 83940DYI-01LFT require?
Both devices operate from a 3.3V nominal supply (VCC = 3.3V ± 5%), consistent with the 83940 family specifications. They are LVPECL output devices and require standard LVPECL termination for proper operation.
Can the 83940DYI-01LFT be used as a drop-in replacement for the 83940DYILF?
Not without verification. Although both share the same package and supply voltage, the "-01" suffix indicates a different configuration. A drop-in replacement is only valid if the input/output logic, control pin functions, and default states are confirmed to be equivalent for the target application by comparing both official datasheets.
What is the function of the 83940 series devices?
The 83940 family devices are 3.3V LVPECL fanout buffers designed to distribute high-speed clock signals. They accept a differential or single-ended input and provide multiple LVPECL outputs with low skew, making them suitable for clock distribution in networking, computing, and telecommunications equipment.
Are the 83940DYILF and 83940DYI-01LFT RoHS compliant?
The "LF" suffix in both part numbers indicates lead-free (Pb-free) construction, and these devices are RoHS compliant as stated in the IDT/Renesas product documentation. The "T" suffix on the 83940DYI-01LFT indicates tape-and-reel packaging.