MPC9824 Data Sheet

CLOCK GENERATOR FOR POWERQUICC AND POWERPC MICROPROCESSORS AND MICROCONTROLLERS

MPC9824 REVISION 2 3/16/16

4

©2016 Integrated Device Technology, Inc.

MPC9824 OPERATION

Crystal Oscillator

The MPC9824 features a fully integrated Pierce oscillator

to minimize system implementation costs. The MPC9824

may be operated with a 25 MHz crystal without other compo-

nents. For operation without external components, the crystal

selection should be of a 25 MHz parallel resonant type with a

load specification of CL = 10 pF. See Table 4 for complete

crystal specifications.

If more precise frequency control is desired, the addition of

capacitors from each of the XTAL_IN and XTAL_OUT pins to

ground may be used to trim the frequency as shown in Figure

3. In this case the recommended crystal should have a CL =

18 pF.

In either case the crystal should be located as close to the

MPC9824 XTAL_IN and XTAL_OUT pins as possible to

minimize any board level parasitic capacitance.

Figure 3 Crystal with Trim Caps

*NOTE: These are recommended values and are subject to change due to specific crystal paramter and board layout. Refer to

ICS Application Notes for futher information on the crystal selection.

Power-Supply Bypassing

The MPC9824 should have all VDD pins bypassed with

0.01 µF capacitors and a minimum of one 1.0 µF capacitor for

the overall package. All capacitors should be located as close

to the package as possible.

An external RC filter from VDD to VDDA is recommended as

shown in Figure 4.

Figure 4. Power Supply Filter

Table 4. Crystal Specifications

Parameter

Value

Value (with trim caps)

Crystal Cut

Fundamental AT Cut

Fundamental AT Cut

Resonance

Parallel Resonance

Parallel Resonance

Shunt Capacitance (CO)

5–7 pF

5–7 pF

Load Capacitance (CL)

18 pF

18 pF

Equivalent Series Resistance (ESR)

20–50



20–50



VDDA

VDD

MPC9824

C1, C2 = 0.01...0.1 F

VDD

CF = 22 F

RF = 10-15 

C2

C1