MC9S08JM16 Datasheet, PDF (127/386 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 9
5 V Analog Comparator (S08ACMPV2)
9.1 Introduction
The analog comparator module (ACMP) provides a circuit for comparing two analog input voltages or for
comparing one analog input voltage to an internal reference voltage. The comparator circuit is designed to
operate across the full range of the supply voltage (rail to rail operation).
NOTE
MC9S08JM16 series devices operate at a higher voltage range (2.7 V to
5.5 V) and do not include stop1 mode. Therefore, please disregard
references to stop1.
9.1.1 ACMP Configuration Information
When using the bandgap reference voltage for input to ACMP+, the user must enable the bandgap buffer
by setting BGBE =1 in SPMSC1 see Section 5.7.7, “System Power Management Status and Control 1
Register (SPMSC1)”. For value of bandgap voltage reference see Appendix A.6, “DC Characteristics.”
9.1.2 ACMP/TPM Configuration Information
The ACMP module can be configured to connect the output of the analog comparator to TPM input capture
channel 0 by setting ACIC in SOPT2. With ACIC set, the TPM1CH0 pin is not available externally
regardless of the configuration of the TPM module.
MC9S08JM16 Series Data Sheet, Rev. 2
Freescale Semiconductor
127