MC88915FN70 Freescale Semiconductor, MC88915FN70 Datasheet - Page 11

• Manufacturer Part Number: MC88915FN70
• Description: IC DRIVER CLK PLL 70MHZ 28-PLCC
• Manufacturer: Freescale Semiconductor
• Type: Clock Driver, Fanout Distribution, Multiplexerr

Specifications of MC88915FN70

• Pll: Yes
• Input: TTL
• Output: CMOS, TTL
• Number Of Circuits: 1
• Ratio - Input:output: 3:8
• Differential - Input:output: No/No
• Frequency - Max: 70MHz
• Divider/multiplier: Yes/Yes
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 28-PLCC
• Frequency-max: 70MHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

TIMING SOLUTIONS
BR1333 — Rev 6
MC88915 System Level Testing Functionality
high), the 2X_Q output is inverted from the selected SYNC input, and the “Q” outputs are divide–by–2 (negative edge triggered)
of the SYNC input, and the Q/2 output is divide–by–4. With FREQ_SEL low the 2X_Q output is divide–by–2 of the SYNC, the “Q”
outputs divide–by–4, and the Q/2 output divide–by–8. These relationships can be seen on the block diagram. A recommended
test configuration would be to use SYNC0 as the test clock input, and tie PLL_EN and REF_SEL together and connect them to
the test select logic. When these inputs are low, the 88915 is in test mode and the SYNC0 input is selected.
input frequency. In the test mode described above, any frequency test signal can be used.
When the PLL_EN pin is low, the VCO is disabled and the 88915 is in low frequency “test mode”. In test mode (with FREQ_SEL
This functionality is needed since most board–level testers run at 1 MHz or below, and the 88915 cannot lock onto that low of an
Figure 7. Representation of a Potential Multi–Processing Application Utilizing the MC88915
CLOCK @ 2f
AT POINT OF USE
DISTRIBUTE
CLOCK @ f
SYSTEM
CLOCK
SOURCE
for Frequency Multiplication and Low Board–to–Board Skew
CLOCK
@ f
MC88915
MC88915
PLL
PLL
PLL
MEMORY
CARDS
2f
2f
2f
11
CMMU
CMMU
CMMU
CMMU
CPU
CPU
MEMORY
CONTROL
CMMU
CMMU
CMMU
CMMU
CMMU
CMMU
CLOCK @ 2f
AT POINT OF USE
CPU
CARD
CPU
CARD
MC88915
MOTOROLA