
87974CYI
www.idt.com
REV. E JULY 26, 2010
3
ICS87974I
LOW SKEW, 1-TO-15,
LVCMOS/LVTTL CLOCK GENERATOR
0
1
÷4
÷2
PLL
2
D
D Q
Q
5
4
0
1
0
1
CLK_SEL
CLK0
CLK1
FB_IN
SEL_A
PLL_SEL
SEL_C
FB_SEL(0:1)
nMR/OE
QA0:QA4
QB0:QB4
QC0:QC3
QFB
SIMPLIFIED BLOCK DIAGRAM
SEL_B
FB_0 FB_1
00
÷4
01
÷6
10
÷8
1
1 ÷12
SEL_C
0÷4
1÷6
SEL_B
0÷2
1÷4
SEL_A
0÷2
1÷4
VCO_SEL
CLK_EN