TWR-MCF51QM-KIT Freescale Semiconductor, TWR-MCF51QM-KIT Datasheet - Page 8

• Manufacturer Part Number: TWR-MCF51QM-KIT
• Description: MCF51QM Tower Kit
• Manufacturer: Freescale Semiconductor
• Series: ColdFire®, Flexis™r
• Type: MCUr

Specifications of TWR-MCF51QM-KIT

• Rohs Compliant: YES
• Contents: 4 Boards, Cable, DVD
• Peak Reflow Compatible (260 C): Yes
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: MCF51QM128

2.2 Clocking
The ColdFire+ MCUs start up from an internal digitally controlled oscillator (DCO). Software can enable
the main external oscillator (EXTAL2/XTAL2) if desired. The external oscillator/resonator for the
Multipurpose Clock Generator (MCG) module can range from 32.768 KHz up to a 32 MHz.
The TWR-MCF51QM provides an 8 MHz ceramic resonator as shown in Figure 4 below and sheet 4 of
the schematics.
Additionally, the TWR-MCF51QM provides an optional crystal that can feed the low-power oscillator
(EXTAL1/XTAL1). The low-power oscillator can be used to clock the low-power timer and other
features of the MCF51QM in very low-power stop modes. Two 0 ohm resistors (not populated be
default) provide a means for isolating EXTAL1 and XTAL1 connections to the crystal circuit so that these
pins can be used for other purposes.
2.3 System Power
When installed into a Tower System, the TWR-MCF51QM can be powered from either an on-board
source or from another source in the assembled Tower System.
In stand-alone operation, the main power source for the TWR-MCF51QM module is derived from the
5.0V input from either the OSBDM USB mini-B connector (J16) or the EzPort header (J18) when a shunt
is placed on jumper J24. Two low-dropout regulators provide 3.3V and 1.8V supplies from the 5.0V
input voltage. Additionally, the 3.3V regulator built into the MCF51QM can be selected. All the user
selectable options can be configured using two headers, J11 and J12.
TWRMCF51QMUM
High-speed analog comparator with 6-bit DAC
Programmable voltage reference
SPI, I
GPIO with pin interrupt support, DMA request capability, digital glitch filtering
2
C (w/ SMBUS support), UART (w/ ISO7816 and IrDA),
TWR-MCF51QM Tower Module User's Manual
Figure 5. Low-power Oscillator Input
Figure 4. Main Oscillator Input
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