Part A
ADG508AKNZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 5168 PCS
- Package
- PDIP-16
- Series
- Interface - Conmutadores analógicos, Multiplexers, Demultiplexeres
Replacement verdict
Compatible functional replacement candidate
The ADG508AKNZ and ADG509FBN are both 8-channel CMOS analog multiplexers sharing a common 16-pin DIP footprint and comparable supply and signal ranges, but they differ in switch architecture and fault-protection behavior. The ADG508AKNZ is a standard multiplexer, while the ADG509FBN adds fault-protected inputs, so substitution is feasible only after validating the fault-protection requirement, channel configuration, and on-resistance tolerance in the target application.
Channel Configuration
Validation required
Package Type
High match
On-Resistance
Validation required
Fault Protection
Not compatible
Parts at a glance
Part B
ADG509FBN
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 8285 PCS
- Package
- DIP-16
- Series
- Interface - Conmutadores analógicos, Multiplexers, Demultiplexeres
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADG508AKNZ | ADG509FBN | Why it matters |
|---|---|---|---|
| Number of Channels | 8 (1:1 mux, 8-to-1) | 4 (differential 4-to-1) | Determines how many signal paths can be switched; an 8-channel single-ended mux is not a drop-in replacement for a 4-channel differential mux. |
| Switch Configuration | Single-ended 8:1 multiplexer | Differential 4:1 multiplexer | Defines whether the device switches single-ended or differential signals, which fundamentally affects circuit topology and substitutability. |
| On-Resistance (typ) | ~280 Ω | ~280 Ω | On-resistance affects signal attenuation and voltage drop; similar values here, but the channel count difference still prevents direct substitution. |
| Fault-Protected Inputs | No | Yes (fault-protected) | Fault protection allows the device to withstand overvoltage on inputs, a critical safety and reliability feature not present in the non-protected part. |
| Supply Voltage Range | ±15 V dual (or +12 V single) | ±15 V dual (or +12 V single) | Supply range must match the system rails; both share similar ranges, but the fault-protected variant may have tighter absolute maximum ratings. |
| Package | PDIP-16 (N) | PDIP-16 (N) | Package compatibility affects PCB footprint; both are 16-pin DIP, but pinout differences due to channel configuration prevent direct swap. |
| Pinout Compatibility | 8-channel single-ended pinout | 4-channel differential pinout | Different internal switch topology results in different pin functions, so the parts are not pin-for-pin interchangeable despite sharing a package. |
| Switching Time (typ) | ~250 ns | ~250 ns | Switching speed impacts multiplexing rate; comparable values mean timing is not the limiting substitution factor, but topology still differs. |
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 | ADG508AKNZ | ADG509FBN |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Part Status | Active | Obsolete |
| Mounting Type | Through Hole | Through Hole |
| Multiplexer / Demultiplexer Circuit | 8:1 | - |
| Number of Circuits | 1 | - |
| On - State Resistance(Max) | 300Ohm | - |
| Channel - to - Channel Matching(ΔRon) | 15Ohm | - |
| Voltage - Supply, Single (V+) | 10.8V ~ 16.5V | - |
| Voltage - Supply, Dual (V±) | ±10.8V ~ 16.5V | - |
| Switch Time(Ton Toff)(Max) | 300ns, 300ns | - |
| Charge Injection | 4pC | - |
| Channel Capacitance(CS(off)CD(off)) | 5pF, 22pF | - |
| Current - Leakage(IS(off))(Max) | 1nA | - |
| Operating Temperature | -40°C ~ 85°C (TA) | - |
Frequently asked questions
What are the primary differences between the ADG508AKNZ and the ADG509FBN?
The ADG508AKNZ is an 8-channel analog multiplexer from the ADG508A family, while the ADG509FBN is a 4-channel differential analog multiplexer from the ADG509F family. The ADG508AKNZ switches eight single-ended inputs to a common output, whereas the ADG509FBN switches four differential input pairs. They also differ in package type and specified operating temperature range per their respective datasheets.
Are the ADG508AKNZ and ADG509FBN pin-compatible?
No. The ADG508AKNZ is supplied in a 16-lead PDIP package, and the ADG509FBN is supplied in a 16-lead PDIP package, but their pin functions differ because one is an 8-channel single-ended multiplexer and the other is a 4-channel differential multiplexer. Pin assignments and channel configurations are not interchangeable, so they cannot be treated as pin-compatible substitutes.
What are the key analog switch specifications of the ADG508AKNZ?
Per the Analog Devices ADG508A datasheet, the ADG508AKNZ is an 8-channel single-ended multiplexer featuring low on-resistance, low leakage current, and TTL/CMOS-compatible logic inputs. It operates from dual supplies and is specified for the commercial temperature range in the KNZ grade. Designers should consult the official datasheet for exact on-resistance, switching time, and supply voltage limits.
What are the key analog switch specifications of the ADG509FBN?
Per the Analog Devices ADG509F datasheet, the ADG509FBN is a 4-channel differential multiplexer with fault-protected inputs, designed to withstand overvoltage conditions on the analog inputs. It offers low on-resistance and is specified for the industrial temperature range in the BN grade. Exact fault-protection thresholds, on-resistance, and switching times should be verified in the official datasheet.
Can the ADG508AKNZ and ADG509FBN be used interchangeably in a design?
No. Because one is an 8-channel single-ended multiplexer and the other is a 4-channel differential multiplexer with fault protection, their channel count, signal topology, and protection features differ. Substitution requires redesign of the signal routing and validation against the target application's requirements; they are not drop-in replacements.
Do both devices support the same supply voltage range?
Both the ADG508A and ADG509F families are designed for dual-supply operation, but the exact specified supply ranges and absolute maximum ratings differ between the two datasheets. The ADG509F additionally includes fault-protected inputs that affect its input voltage handling. Verify the specific supply limits for each grade in the respective Analog Devices datasheets before use.
Which device is better suited for differential signal switching?
The ADG509FBN is the appropriate choice for differential signal switching because it is a 4-channel differential multiplexer that switches input pairs. The ADG508AKNZ is an 8-channel single-ended multiplexer and is not intended for differential pair routing. Selection should be based on the signal topology required by the application.
Which device offers fault protection on its analog inputs?
The ADG509FBN offers fault-protected analog inputs as part of the ADG509F family design, allowing it to tolerate overvoltage conditions on the analog inputs. The ADG508AKNZ, from the ADG508A family, is not specified with the same fault-protection feature. Confirm the exact fault-protection ratings in the ADG509F datasheet for the target application.