DG417AK - 35 Ohm SPST Analog Switch IC | Vishay Siliconix
Артикул: DG417AK ✗ Снят с производстваDG417AK Обзор
An analog switch is a semiconductor device that routes an analog signal between circuit nodes under digital control. The DG417 belongs to the broader family of analog switches and multiplexers, which sit between sensors, amplifiers and converters on one side, and a shared signal chain on the other. A single-pole single-throw (SPST) switch provides one signal path that is either connected or broken, while a normally-closed version holds the path closed until a control signal opens it, which is the safe default for fail-safe routing.
Key features include guaranteed on-resistance matching between switches of 3 ohm max and guaranteed on-resistance flatness across the signal range of 4 ohm max, both improvements over earlier generations of this device family. Fast switching action is specified at tON = 100 ns, and ultra-low power requirements of PD = 35 nW keep the supply current draw negligible in battery-backed and standalone measurement fixtures. The design is CMOS monolithic, so the part draws essentially no quiescent bias current.
Because the switch is CMOS and complementary-driven, the control pins accept TTL and CMOS levels, and the input stage tolerates a wide analog signal range of +/-15 V on the switched terminals. On-resistance matching and flatness specifications are what make the device usable for precision measurement: they bound the error introduced when the same source impedance drives different switched paths, which is the dominant error term in many 16-bit and 18-bit front ends.
Typical applications include sample-and-hold front ends for high-resolution ADCs, precision instrument amplifiers in test and measurement systems, audio and low-frequency signal routing in broadcast and studio equipment, medical monitoring front ends, and general-purpose routing in industrial control and data acquisition modules.
The primary design consideration is the always-present 35 ohm series resistance in the closed state, which must be included in the system noise and offset budget; keep the switch close to the high-impedance input it serves so that leakage and stray capacitance do not degrade accuracy. Because the DG417AK is a legacy order code, confirm supply availability and consider the currently active equivalents listed below for new designs.
This page brings together the electrical characteristics, the exact package and pinout information, drop-in replacements with quantified parameter differences, and practical layout and signal-integrity guidance that are not consolidated anywhere in the original manufacturer documentation.
Аналоги без доработки для DG417AK — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
Варианты в этой серии
Модели той же серии, совместимые без доработки с DG417AK (тот же форм-фактор и посадочное место) — отличается по Number of Channels, Package, Switch Configuration.
DG417AD
✅ Прямая замена ⚠️ Характеристики не проверены📋 Справочный аналог (нет в каталоге)
DG417AY+
✅ Прямая замена ⚠️ Характеристики не проверены📋 Справочный аналог (нет в каталоге)
DG417CY+
✅ Прямая заменаУточнить цену
Открыть даташит →ADG417BRZ
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
DG417AK Максимальные параметры и электрические характеристики
| Switch Configuration | SPST, normally closed (NCX1), 1:1 |
| Number of Channels | 1 |
| On-Resistance (Max) | 35 ohm |
| On-Resistance (Typ) | 20 ohm |
| On-Resistance Matching Between Switches | 3 ohm max |
| On-Resistance Flatness Over Signal Range | 4 ohm max |
| Analog Signal Range | +/-15 V |
| Turn-On Time (tON) | 100 ns |
| Power Dissipation (PD) | 35 nW |
| Logic Compatibility | TTL and CMOS compatible |
| Process Technology | CMOS monolithic |
| Корпус | 8-lead SOIC (MS-8) |
| Тип монтажа | Surface Mount |
| Статус RoHS | Compliant |
Руководство по цоколевке DG417AK в корпусе 8-lead soic (ms-8)
Цоколевка для DG417AK (корпус 8-lead soic (ms-8)). Нумерация выводов, функции и схемы подключения определены в техническом описании производителя. Обратитесь к нему для точного посадочного места и рекомендаций по пайке.
Нет подробных данных о распиновке для DG417AK.
Обратитесь к даташиту для полной конфигурации выводов.
Типичное применение
DG417AK подходит для 6 применениеs: High-Resolution ADC Sample-and-Hold Front End, Precision Test and Measurement Instrumentation, Audio and Low-Frequency Signal Routing, Medical Monitoring and Biosignal Acquisition, Industrial Data Acquisition and Sensor Multiplexing, Legacy Test Fixture Repair and Retrofit.
High-Resolution ADC Sample-and-Hold Front End
The DG417AK is well suited to gating a sensor or transducer signal into the input of a high-resolution ADC, where the normally-closed path holds the source connected between conversions and opens only during acquisition. With a maximum on-resistance of 35 ohm and a guaranteed on-resistance matching of 3 ohm max, the switch contributes a bounded, repeatable series impedance rather than an unknown one, which keeps the gain error of the following amplifier predictable. The 100 ns turn-on time supports short acquisition windows, and the 35 nW power dissipation keeps the part invisible to battery-powered data loggers. Place the device within a few millimetres of the ADC input pin to minimise stray capacitance during settling.
Рекомендуется
Precision Test and Measurement Instrumentation
In bench instruments and automated test equipment, the DG417AK routes calibration and stimulus signals between the DUT and the measurement chain. Its guaranteed on-resistance flatness of 4 ohm max across the signal range means the insertion error does not drift as the signal amplitude changes, and the on-resistance matching spec of 3 ohm max keeps channel-to-channel comparisons repeatable across a fixture with many switched inputs. The device is TTL and CMOS compatible, so it is driven straight from a digital control port or from a microcontroller general-purpose output with no level translation. The 8-lead SOIC footprint keeps the layout compact for multi-channel switching cards.
Рекомендуется
Audio and Low-Frequency Signal Routing
The DG417AK is frequently used for audio and low-frequency analog routing in broadcast, studio and musical instrument equipment, where a 35 ohm series resistance is acceptable for line-level signals and where the normally-closed default keeps the signal path connected when control logic is unpowered. Because the switch adds resistance rather than switching noise, it does not generate the harmonic artifacts associated with a switching power stage, so audio quality is preserved. The 100 ns switching action is far faster than any audio bandwidth requirement, and the negligible 35 nW power dissipation suits battery-powered active instruments. Care should be taken on high-impedance source circuits, where the fixed resistance will attenuate the signal.
Рекомендуется
Medical Monitoring and Biosignal Acquisition
In patient monitoring and biosignal acquisition equipment, the DG417AK can isolate a sensor amplifier from the acquisition chain, protecting the front end when the channel is not in use. The normally-closed configuration provides a defined, low-impedance connection during measurement, and the bounded on-resistance matching of 3 ohm max limits the gain error introduced by the switch itself. The device draws negligible power at 35 nW, which matters for portable and wearable units running on small battery budgets. Because the DG417AK is a legacy order code, medical product designs should qualify a currently maintained equivalent such as the ADG417BRZ during design verification to protect supply continuity over the product life.
Рекомендуется
Industrial Data Acquisition and Sensor Multiplexing
The DG417AK fits industrial data acquisition modules that must present a single amplifier to many sensors sequentially. Holding the closed-path resistance at 35 ohm max and flat to within 4 ohm across the signal range means the module can apply one calibration constant across all channels instead of calibrating per switch position. TTL and CMOS control compatibility lets a microcontroller or an FPGA directly drive the select line, and the surface-mount SOIC package fits densely populated analog boards. For long cable runs and high-impedance sensors, add a buffer amplifier close to the switch so that the fixed 35 ohm does not combine with cable capacitance to slow settling.
Рекомендуется
Legacy Test Fixture Repair and Retrofit
The DG417AK remains useful as a repair and retrofit component for instruments built around the original Maxim and Vishay DG417 family, because identical order codes and equivalent modern parts are still available in the same 8-lead SOIC footprint. An ADG417BRZ or DG417CY+ can be soldered directly onto an existing board without respinning the PCB, which is the fastest route to restoring a failed channel. Verify the pin numbering in the SOIC drawing and the control-logic polarity before fitting, since the family is offered in several lead configurations. In production retrofit programs, prefer a currently maintained equivalent so that the next failure cycle does not require another legacy hunt.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для DG417AK — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар | DG417AD | DG417AY+ | DG417CY+ | ADG417BRZ |
|---|---|---|---|---|---|
| Package | 8-lead SOIC (MS-8) | 8-lead SOIC - same | 8-lead SOIC - same | 8-lead SOIC - same | 8-lead SOIC - same |
| Brand | Vishay Intertechnology | Vishay Intertechnology | Vishay Intertechnology | Maxim Integrated | Analog Devices |
| Switch Configuration | SPST normally closed (NCX1), 1 channel | SPST normally closed (NCX1), 1 channel | SPST normally closed (NCX1), 1 channel | SPST normally closed (NCX1), 1 channel | SPST normally closed (NCX1), 1 channel |
| On-Resistance (Max) | 35 ohm | 35 ohm | 35 ohm | 35 ohm | 35 ohm class |
| Logic Compatibility | TTL and CMOS compatible | TTL and CMOS compatible | TTL and CMOS compatible | TTL and CMOS compatible | CMOS control logic |
| Lifecycle Status | Obsolete / legacy order code | Legacy order code | Legacy order code | Maintained order code | Currently maintained |
Ключевые отличия
- Guaranteed on-resistance matching makes channel-to-channel error repeatable (против DG417CY+)
- Continuously maintained cross-brand substitute exists for supply continuity (против ADG417BRZ)
- Ultra-low power dissipation suits portable and battery-backed instruments (против DG417AD)
Заметки по проектированию
The closed-path 35 ohm maximum on-resistance is a hard series element in the signal chain, so it must be included in the noise and gain error budget of whatever follows the switch. Estimated: with a 20 ohm typical on-resistance and a 10 kohm amplifier input impedance, the divider ratio of 10000/(10000+20) produces roughly 0.2 percent gain error, and the associated Johnson noise contribution of a 20 ohm resistor over 1 kHz bandwidth is about 0.58 uVrms. Place the DG417AK physically adjacent to the high-impedance input it serves so that switch capacitance and PCB stray capacitance do not dominate the settling behaviour.
Route the switched signal traces as short and guarded as possible. Keep the control (IN) trace away from the analog path to avoid capacitive coupling of the 100 ns switching edge into the switched node, and terminate the control line with a pull resistor so the normally-closed state is well defined during power-up when the logic driver is in high-impedance. Place a 0.1 uF ceramic decoupling capacitor close to the supply pins and provide a solid ground plane directly under the device to minimise return-path inductance during the fast turn-on edge.
Two traps recur with this device family. First, the DG417 family exists in multiple lead configurations, including SOIC, plastic DIP and ceramic DIP variants under order codes such as DG417AK, DG417AD, DG417AY+, DG417DY and DG417LDJ; a ceramic or through-hole code will not fit an SOIC land pattern, so confirm the package before ordering. Second, the normally-closed part differs from the normally-open companion in its default state, and swapping them silently inverts the fail-safe behaviour of the instrument. Verify the truth table in the manufacturer datasheet for the exact order code fitted.
Информация о соответствии
RoHS compliance is indicated for the Vishay Siliconix ordering information. AEC-Q100 qualification, REACH status and halogen-free declarations are not stated for this order code and are therefore recorded as unknown.
