Part A
74HC4066D
東芝電晶體與存儲
- Lifecycle
- Active
- Stock
- 7546 件
- Package
- SOIC-14
- Series
- 介面-類比開關、多工器、解復用器
Replacement verdict
Not a drop-in replacement
The 74HC4066D and 74HC4051D,652 are not functionally interchangeable despite sharing the same 74HC CMOS logic family and SO-16 package. The 74HC4066D provides four independent bilateral analog switches with individual control, while the 74HC4051D,652 is an 8-channel analog multiplexer/demultiplexer with a single 3-bit address decoder and one common I/O path. This fundamental difference in switch topology, channel count, and control interface prevents direct substitution in existing designs without circuit redesign.
Different switch topology
Different channel count
Different control interface
Different signal routing
Parts at a glance
Part B
74HC4051D,652
Nexperia美國公司
- Lifecycle
- Active
- Stock
- 4733 件
- Package
- SOIC-16
- Series
- 介面-類比開關、多工器、解復用器
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 74HC4066D | 74HC4051D,652 | Why it matters |
|---|---|---|---|
| Function | Quad bilateral switch (4 independent SPST switches) | Single 8-channel analog multiplexer/demultiplexer | Defines the core signal-routing behavior; these parts are not functionally interchangeable. |
| Number of Channels / Switches | 4 bilateral switches | 8 channels (1-of-8 selection) | Determines how many independent signals can be routed or selected. |
| Control Inputs | 4 independent control pins (one per switch) | 3 address select pins (S0, S1, S2) plus enable | Affects logic interface complexity and how the device is driven by a controller. |
| On-Resistance (typ) | ~50 Ω at VCC = 4.5 V | ~80 Ω at VCC = 4.5 V | Lower on-resistance reduces signal attenuation and voltage drop in analog paths. |
| Supply Voltage Range | 2 V to 10 V | 2 V to 10 V | Both support similar logic-level supplies, but confirm compatibility with the target system rails. |
| Propagation Delay (typ) | ~7 ns at VCC = 4.5 V | ~10 ns at VCC = 4.5 V | Impacts maximum usable switching speed in multiplexing or signal-gating applications. |
| Package | SO-14 | SO-16 | Different pin counts and footprints prevent direct drop-in PCB replacement. |
| Pin Count | 14 | 16 | Board layout and socket compatibility depend on matching pin count. |
| Typical Application | Analog signal gating, sample-and-hold, modulation | Analog/digital multiplexing, signal selection, data acquisition | Highlights the intended use case and whether the part fits the system architecture. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 74HC4066D | 74HC4051D,652 |
|---|---|---|
| Supplier | - | Nexperia USA Inc. |
| Part Status | Active | Obsolete |
| Multiplexer / Demultiplexer Circuit | 1:1 | 8:1 |
| Number of Circuits | 4 | 1 |
| On - State Resistance(Max) | 80Ohm | 120Ohm |
| Channel - to - Channel Matching(ΔRon) | 5Ohm (Typ) | 6Ohm |
| Voltage - Supply, Single (V+) | 2V ~ 12V | 2V ~ 10V |
| Voltage - Supply, Dual (V±) | - | ±1.5V ~ 5V |
| Switch Time(Ton Toff)(Max) | 12ns, 12ns | 51ns, 42ns |
| -3 dB Bandwidth | 200MHz | 180MHz |
| Channel Capacitance(CS(off)CD(off)) | 3pF | 3.5pF |
| Current - Leakage(IS(off))(Max) | 100nA | 400nA |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 125°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
| Crosstalk | -60dB @ 1MHz | - |
Frequently asked questions
What is the main functional difference between the 74HC4066D and the 74HC4051D,652?
The 74HC4066D contains four independent bilateral analog switches (quad SPST), while the 74HC4051D,652 is a single 8-channel analog multiplexer/demultiplexer (1-of-8). The 74HC4066D is used for switching four separate signal paths, whereas the 74HC4051D,652 selects one of eight channels to a common input/output.
Are the 74HC4066D and 74HC4051D,652 pin-compatible?
No. The 74HC4066D is typically supplied in a 14-pin SOIC package, while the 74HC4051D,652 is supplied in a 16-pin SOIC package. They have different pin counts and pin functions, so they are not drop-in replacements for each other.
Can the 74HC4066D be used to replace the 74HC4051D,652 in an existing design?
No, not directly. The 74HC4066D provides four independent SPST switches, while the 74HC4051D,652 provides an 8-to-1 multiplexer function with three digital address inputs. Replacing one with the other would require significant circuit redesign and additional logic to emulate the multiplexer addressing.
What are the typical on-state resistance characteristics of these devices?
Both the 74HC4066D and 74HC4051D,652 are specified with a typical on-state resistance (Ron) in the range of tens of ohms at 4.5 V supply, with the exact value depending on supply voltage and temperature. For precise Ron limits, consult the respective manufacturer datasheets, as values vary by manufacturer and test conditions.
Do both devices support bidirectional analog signal switching?
Yes. The 74HC4066D is a bilateral switch designed for bidirectional analog or digital signal transmission. The 74HC4051D,652 is also bidirectional, allowing it to be used as either a multiplexer or a demultiplexer for analog signals within the specified voltage range.
What supply voltage range is common to both the 74HC4066D and 74HC4051D,652?
Both devices are members of the 74HC family and typically operate over a supply voltage range of 2 V to 6 V. Some manufacturers may specify a slightly wider or narrower range, so the exact limits should be verified from the specific manufacturer datasheet.
Which device is better suited for routing eight separate signal channels to one output?
The 74HC4051D,652 is the appropriate choice for routing eight channels to one output, as it is an 8-channel analog multiplexer/demultiplexer. The 74HC4066D would require additional external logic and multiple packages to achieve the same function.
Are the control inputs of the 74HC4066D and 74HC4051D,652 compatible with standard CMOS logic levels?
Yes. Both devices have control inputs that are compatible with standard CMOS logic levels when operated at the same supply voltage. The 74HC4066D has four independent control inputs, while the 74HC4051D,652 has three address inputs plus an enable input.