DG408 - 8-Channel CMOS Analog Multiplexer 100Ω | Renesas
MPN: DG408 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.1 | $3.10 |
| 10 | $2.79 | $27.90 |
| 100 | $2.36 | $236.00 |
| 500 | $1.98 | $990.00 |
| 1,000 | $1.72 | $1,720.00 |
DG408 Overview
An analog multiplexer is a signal-routing device that selects one of several analog inputs and connects it to a single output using an array of CMOS transmission gates controlled by digital address inputs. In the signal-chain hierarchy, the DG408 sits between sensors or signal sources and an ADC or amplifier, functioning as a digitally controlled switch matrix within the broader family of analog switches and multiplexers in data acquisition systems.
Key features include guaranteed channel-to-channel on-resistance matching of 8 ohms max and on-resistance flatness of 9 ohms max, which preserve signal accuracy when switching between channels. The device offers TTL/CMOS-compatible digital inputs over the full operating temperature range, an ENABLE input for paralleling multiple muxes, and break-before-make switching to prevent momentary channel shorting. ESD protection exceeds 2000 V per datasheet specifications.
Technically, the DG408 integrates eight CMOS analog switches, a TTL/CMOS-compatible 3-bit decoder, an internal voltage reference for logic thresholds, and an enable circuit on one monolithic die. Rail-to-rail analog signal handling allows the full supply range to be switched, and input leakage current is limited to 5 nA max at +85C, minimizing signal errors in high-impedance paths.
Typical applications include high-speed data acquisition front ends, audio signal switching and routing, automatic test equipment (ATE) systems, and avionics, where its low leakage and fast, clean switching fit dense channel-scanning designs.
When designing with the DG408, observe the break-before-make timing margin and keep the digital address lines clean, as slow edges can cause transient feedthrough during decoding.
This page synthesizes drop-in alternative cross-references, application guidance, and design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for DG408 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
DG408L
✅ Drop-In📋 Reference alternative (not in catalog)
DG508A
✅ Drop-In📋 Reference alternative (not in catalog)
ADG408
✅ Drop-In📋 Reference alternative (not in catalog)
ADG408TQ
✅ Drop-In📋 Reference alternative (not in catalog)
DG408 Maximum Ratings & Electrical Characteristics
| Function | Single 8-channel CMOS analog multiplexer |
| On-Resistance (max) | 100 ohm |
| Channel-to-Channel On-Resistance Matching (max) | 8 ohm |
| On-Resistance Flatness (max) | 9 ohm |
| Charge Injection (max) | 15 pC |
| Input Leakage Current (max) | 5 nA at +85C |
| Power Consumption (max) | 1.25 mW |
| Logic Compatibility | TTL/CMOS |
| ESD Protection | > 2000 V |
| Analog Signal Range | Rail-to-rail (V+ to V-) |
| Switching Action | Break-before-make |
| Enable Input | Yes |
| Supply Configuration | Dual or single supply |
| Package Options | PDIP-16, SOIC-16, TSSOP-16 |
| Mounting Type | Surface Mount / Through Hole (package dependent) |
| Applications | Data acquisition, audio routing, ATE, avionics |
DG408 Pin Configuration
| Pin 1 | EN — Enable input (logic HIGH disables all switches) |
| Pin 2 | V- — Negative supply |
| Pin 3 | GND — Ground |
| Pin 4 | S4 — Analog channel 4 input |
| Pin 5 | A2 — Address input bit 2 |
| Pin 6 | A1 — Address input bit 1 |
| Pin 7 | S5 — Analog channel 5 input |
| Pin 8 | S6 — Analog channel 6 input |
| Pin 9 | S7 — Analog channel 7 input |
| Pin 10 | A0 — Address input bit 0 |
| Pin 11 | COM — Common output (connects to selected channel) |
| Pin 12 | S8 — Analog channel 8 input |
| Pin 13 | S3 — Analog channel 3 input |
| Pin 14 | S2 — Analog channel 2 input |
| Pin 15 | S1 — Analog channel 1 input |
| Pin 16 | V+ — Positive supply |
Typical Applications
DG408 is suitable for 6 applications: High-Speed Data Acquisition, Audio Signal Switching and Routing, Automatic Test Equipment (ATE), Avionics Signal Selection, Industrial Process Monitoring, Medical Instrumentation Front Ends.
High-Speed Data Acquisition
The DG408 is explicitly listed by the Vishay datasheet as a high-speed data acquisition component. Its role is to scan up to eight sensor or signal channels into a single ADC input, saving cost and board area versus one converter per channel. The 100 ohm max on-resistance with 9 ohm max flatness keeps channel-to-channel gain error predictable when paired with a high-input-impedance buffer, while 5 nA max input leakage at +85C prevents offset errors in high-impedance sensor paths such as photodiodes or pH probes. Break-before-make switching ensures two sources never short during address changes, and the 15 pC max charge injection limits sampling transients that would otherwise settle into the ADC aperture. The ENABLE pin lets several DG408 devices share one ADC, building 16- or 24-channel systems with clean hierarchy.
Recommended
Audio Signal Switching and Routing
Audio signal switching and routing is a named application for the DG408 in the Vishay datasheet. In line-level audio, the mux selects between sources such as CD, tuner, and auxiliary inputs and feeds a single preamplifier path. The 100 ohm max on-resistance introduces only small insertion loss when driving typical 10k ohm or higher loads, and the 9 ohm max flatness keeps channel-to-channel level matching within a fraction of a dB. Critically, the 15 pC max charge injection minimizes the click-and-pop artifacts that cheaper switches produce during source changes, and low crosstalk from the CMOS switch architecture preserves channel separation. The TTL/CMOS-compatible address inputs allow direct control from a microcontroller GPIO for source-selection firmware.
Recommended
Automatic Test Equipment (ATE)
The Vishay DG408 datasheet names ATE systems as a primary application. In a test matrix, the DG408 routes stimulus or measurement lines to many device-under-test pins under host control, and the ENABLE input supports tiered multiplexer trees so hundreds of nodes can be addressed with a handful of logic lines. Guaranteed 8 ohm max channel matching is essential here: it means calibrations performed on one channel remain valid across all eight, reducing test-system error budgets and recharacterization effort. The 1.25 mW max power consumption keeps self-heating negligible in dense switch cards, preserving measurement drift specifications, and ESD protection above 2000 V improves robustness in production-floor handling where test points are frequently accessed.
Recommended
Avionics Signal Selection
Avionics is listed in the Vishay datasheet as a DG408 application domain. Aircraft sensor panels must multiplex signals from altitude, airspeed, temperature, and pressure transducers into flight-data acquisition units, often across wide temperature ranges and in the presence of noisy power buses. The DG408's TTL-compatible control inputs over the full specified operating temperature range allow direct interfacing with legacy avionics logic families, while rail-to-rail analog signal handling accommodates the varied sensor output ranges without additional level shifting. The low 5 nA max leakage at +85C preserves accuracy in high-impedance sensor loops, and the monolithic CMOS construction with an internal logic-threshold voltage reference keeps decode behavior stable as supply rails vary in flight.
Recommended
Industrial Process Monitoring
In industrial monitoring, the DG408 scans thermocouples, RTDs, and 4-20 mA derived voltage signals into a shared instrumentation amplifier and ADC. The 100 ohm switch resistance forms a divider with the source impedance, so the 9 ohm max flatness bounds the resulting gain error across channels - with a 1M ohm buffer input the error is under 0.01 percent. The 8 ohm max channel matching means a single calibration constant applies system-wide, simplifying firmware correction. Wide dual-supply operation (e.g., plus/minus 15 V class rails) lets bipolar sensor signals pass directly, and the ENABLE pin supports zoning large plants into mux trees. Low 1.25 mW power consumption suits passive, low-heat DIN-rail mounted acquisition modules.
Recommended
Medical Instrumentation Front Ends
Patient-monitoring and diagnostic equipment multiplexes multiple biopotential or sensor channels into one measurement chain, and the DG408 fits this role with characteristics that matter for medical safety and accuracy. The 5 nA max input leakage at +85C prevents bias currents from polarizing electrodes, the 15 pC max charge injection avoids stimulating artifacts when switching ECG or EEG channels, and low power (1.25 mW max) supports battery-operated portable monitors. Break-before-make switching guarantees that electrode channels never short to each other during scan transitions - important for both measurement integrity and patient protection when combined with input limiting resistors. The TTL/CMOS-compatible control simplifies interface to the system microcontroller or FPGA.
Recommended
Recommended Products Summary
Engineering reference data for DG408 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADG408 | ADG408TQ | DG408L | DG508A |
|---|---|---|---|---|---|
| Package | PDIP-16 / SOIC-16 / TSSOP-16 | SOIC-16 - same footprint | SOIC-16 - same footprint | SOIC-16 - same footprint | SOIC-16 - same footprint |
| Brand | Renesas Electronics | Analog Devices | Analog Devices | Vishay Intertechnology | Renesas Electronics |
| Architecture | Single 8-channel CMOS mux | Single 8-channel mux | Single 8-channel mux | Single 8-channel BiCMOS mux | Single 8-channel mux |
Key Differentiators
- Guaranteed channel matching of 8 ohms max (vs DG508A)
- Dual-supply rail-to-rail analog handling (vs DG408L)
- Trusted second-source ecosystem (vs ADG408)
Design Notes
Do not switch two low-impedance sources without relying on break-before-make timing. The DG408 guarantees the previous channel opens before the new one closes, but if your address lines slew slowly, decode transitions can pass through intermediate states - drive A0/A1/A2 from clean logic with edges fast enough for the datasheet setup/hold times. Also remember that EN is not a channel select: verify polarity in firmware, since enabling multiple DG408 devices whose outputs are tied together will short their selected channels.
The 100 ohm max on-resistance forms a divider with the load. For a 10k ohm load the insertion error is about 1 percent; for precision designs buffer the COM output with a high-input-impedance op-amp (1M ohm or greater) so the Ron error drops below 0.01 percent. The 9 ohm max flatness bounds channel-to-channel gain spread - with a buffered output, all eight channels stay within roughly 0.001 percent of each other, allowing a single system calibration constant.
Keep the analog source traces to S1-S8 short and away from the A0-A2 address lines, which carry fast digital edges that can couple switching spikes into the selected channel via the 15 pC charge-injection path. Decouple V+ and V- pins with 100 nF ceramics placed within a few millimeters. Ground the unused guard area under the COM trace to reduce leakage; at 5 nA max input leakage the die is clean, but PCB contamination can dominate if flux residue remains.
Compliance Information
Compliance status was not stated in the retrieved web data; verify RoHS/REACH status on the Renesas product page for the specific package suffix before procurement.
