C8051F99x Ultra Low Power Touch Sense MCUs​

The C8051F99x family of ultra low power capacitive sensing microcontroller (MCU) devices provide the lowest power and highest sensitivity touch sensing solution for capacitive buttons, sliders, wheels and capacitive proximity sensing.
Architected from the popular C8051F9xx platform, the device combines the industry-leading low power technology of the C8051F9xx family with the fast and accurate capacitive sensing features of the C8051F7xx/8xx families to address fast-growing capacitive touch applications.
C8051F990, F991, F996, F997 touch sense MCUs feature sub micro amp (<1 μA) wake on touch average current consumption, 150 µA/MHz active mode and multiple sleep modes as low as 10 nA. With up to 14 capacitive sensing inputs and a patent-pending charge timing hardware capacitance to digital converter, the C8051F99x family achieves unparalleled touch sensitivity, speed and ultra-low power in packages as small as a 3 mm x 3 mm QFN20.


  • High-speed pipelined 8051-compatible microcontroller core (up to 25 MIPS)
  • Industry’s lowest active & sleep currents
  • 150 µA/MHz active mode
  • 10 nA sleep mode
  • 50 nA sleep mode with brown-out protection
  • 300 nA sleep mode with internal oscillator
  • 14 input charge timing capacitance to digital converter
  • 12-bit 75 ksps single-ended ADC
  • 6-bit current reference
  • Precision calibrated 24.5 MHz internal oscillator
  • SmaRTClock oscillator
  • 8 kB of on-chip Flash memory
  • 512 bytes of on-chip RAM
  • Implemented SMBus/I2C, UART and SPI serial interfaces
  • Four general-purpose 16-bit timers
  • Programmable Counter/Timer Array (PCA)
  • On-chip internal voltage reference
  • On-chip watchdog timer
  • On-chip power-on reset and supply monitor
  • On-chip voltage comparator
  • 17 general purpose I/O
  • In-system, full-speed, non-intrusive debug interface (on-chip)


Featured Application Notes



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Data Sheet (3)

Data Short (1)

C8051F99x Data Short

Errata (1)

C8051F99x Rev A/B Errata

User Guides (4)

Quick Start Guide (2)

Application Notes (12)

White Papers (10)

Miscellaneous (1)

C2 Specification

PCN (4)


Development Kits


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Design Tools

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Software (35)

Schematics/Layout (9)

Training (5)

Product Matrix
Part NumberDev KitDatasheetMCU CoreMHzFlashRAMDig I/O PinsADC 1USBCap SenseTemp SensorTimers (16-bit)PCA ChannelsADC 2DACComparatorsUARTSPII2CHS I2C SlaveI2SEMIFCANLINLCD SegmentsAESAEC-Q100Package TypePackage SizeInternal Osc.VREFDebug InterfaceOther

8051258 kB0.51612-bit, 9-ch., 75 kspsYesYes431111NoNoQFN203x3 mm±2%YesC213 touch channels; Low Power; RTC

8051258 kB0.516YesNo431111NoNoQFN203x3 mm±2%NoC213 touch channels; Low Power; RTC

8051258 kB0.51712-bit, 10-ch., 75 kspsYesYes431111NoNoQFN244x4 mm±2%YesC214 touch channels; Low Power; RTC

8051258 kB0.51712-bit, 10-ch., 75 kspsYesYes431111NoNoQSOP248.65x3.90 mm±2%YesC214 touch channels; Low Power; RTC

8051258 kB0.517YesNo431111NoNoQFN244x4 mm±2%NoC214 touch channels; Low Power; RTC

8051258 kB0.517YesNo431111NoNoQSOP248.65x3.90 mm±2%NoC214 touch channels; Low Power; RTC


    Product Matrix





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