Hardware
1 hardware offering
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Embedded Board SolutionsEmbedded SW: Multiple Switch Detection Interface Software Driver
Switch Detection Interface, 22 I/Os, Programmable Wetting Current, Temp Sensor, 3.3 V / 5.0 V SPI
MC34978 Receive alerts
The NXP® MC34978 is a multiple switch detection interface (MSDI) designed to detect the closing and opening of up to 22 switch contacts in industrial environments.
- The switch status, either open or closed, is transferred to the microprocessor unit through a serial peripheral interface (SPI)
- This SMARTMOS® device also features a 24-to-1 analog multiplexer for reading analog inputs
- Individually selectable input currents are available in Normal and Low-Power Mode (LPM), as needed in the application
- A battery and temperature monitor are included in the IC and are available via the AMUX pin
- This product interfaces with any microcontroller that supports SPI communications
Product Details
Block Diagram
Features
Key Features
- Designed to operate 4.5 V ≤ VBATP ≤ 36 V
- Switch input voltage range -14 V to VPWR, 36 V Max.
- Interfaces directly to an MCU using 3.3 V / 5 V SPI protocol
- Selectable wake-up on change of state
- Selectable wetting current (2, 6, 8, 10, 12, 14, 16, or 20 mA)
- 8 programmable inputs (switches to battery or ground) and 14 switch-to-ground inputs
- Typical standby current - VBATP = 30 uA and VDD = 10 uA
- Integrated battery and temperature sensing
- Switch monitoring device function
- Package termination count: 32
- HSOP32 and HVQFN32 package type
- SPI interface and input control
- Load supply voltage 4.5 V (Min), 36 V (Max)
- Ambient operating temperature -40 °C (Min), 85 °C (Max)
Product Longevity Program
- This product is included in the NXP Product Longevity Program ensuring a stable supply of products for your embedded designs. The The MC34978 is included in the 10-year program
Documentation
Quick reference to our documentation types.
4 documents
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Application Note
AN4388: Quad Flat Package (QFP) – Application Note
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Application Note
AN5322, TPMS Wheel Location Introduction and Main Concepts
Design Resources
Engineering Services
To get further assistance directly from NXP, please see our Engineering Services.
2 engineering services
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Independent Design House (IDH)
Embedded Software Design
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Independent Design House (IDH)
Hardware Design Services
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