Murata PKM Piezoelectric Audio Alarms

Part Number Information
Part #: Price/Availability:
PKM24 SPH Buy Now
PKM30 SPTH Buy Now

Murata's PKM family of self-drive piezoelectric sounders feature a three-element internal piezo diaphragm for generation of a single (fixed-tone) audio signal. An external drive circuit which utilizes the 3-element diaphragm as the frequency-determining component is required. A type 2N3904 NPN transistor or equivalent can serve as a suitable active device for the drive circuit. Supply voltages from 3.0 to 20.0Vdc are acceptable, and SPL (Sound Pressure Level) of 75-90 dB @ 10cm using a 12Vdc supply is typical. All products are RoHS compliant.


  • Fixed frequency tone (2.0, 2.5, 3.8kHz) 
  • Vertical or horizontal mounting 
  • Low current consumption 
  • SElf-resonant frequency regulation 
  • Non-electromagnetic operation 
  • Selected for best human hearing 
  • Design flexibility 
  • Best for battery-powered applications 
  • Recommended for high-SPL requirements 
  • No EMI Concerns


  • Alarms: Smoke, Toxic Gas, and Intruder 
  • Alerts: Home Appliances, etc. 
  • Audio Feedback: Games, Toys, etc.