IDT
®
Low Power Clock for Intel Atom
®
-Based Systems 1561C — 08/24/11
9LPRS436C
Low Power Clock for Intel Atom
®
-Based Systems
3
Pin Description
PIN # PIN NAME TYPE DESCRIPTION
1 **FS3/12_288M_2x I/O Fre
uenc
select latch in
ut
in / 12.288MHz out
ut, 3.3V
2 VDD12_288 PWR Power for 12.288MHz PLL and out
ut buffer, nominal 3.3V.
3PEREQ1# IN
Real-time input pin that controls SATACLK and PCIEXCLK outputs that are
selected through the SMBus. 1 = selected outputs are disabled, 0 = selected
out
uts are enabled.
4PEREQ2# IN
Real-time input pin that controls SATACLK and PCIEXCLK outputs that are
selected through the SMBus. 1 = selected outputs are disabled, 0 = selected
out
uts are enabled.
5 **FS4/PCICLK0_2x I/O Fre
uenc
select latch in
ut
in / 3.3V PCI clock out
ut.
6 GND PWR Ground
in.
7 VDDPCI PWR Power su
l
for PCI clocks, nominal 3.3V
8 **ITP_EN/PCICLK_F0_2x I/O
ITP Enable Latched Input/Free Running PCI clock output.
ITP_Enable Selects the functionality of the CPU_ITP/SRC output as follows:
1 = CPU_ITP output
0 = SRC out
ut
9PEREQ3# IN
Real-time input pin that controls PCIEXCLK outputs that are selected through
the SMBus. 1 = selected outputs are disabled, 0 = selected outputs are
enabled.
10 *SEL12_48#/12_48MHz_2x I/O
Latched select input for 12/48MHz output. 1=12MHz, 0=48MHz. 12/48MHz
clock out
ut.
11 VDD PWR Power su
l
, nominal 3.3V
12 FSLA/USB48_2x I/O
3.3V tolerant input for CPU frequency selection. Low voltage threshold inputs,
see input electrical characteristics for Vil_FS and Vih_FS values. / 48.00MHz
USB cloc
13 GND PWR Ground
in.
14 DOTT_96MHzLR OUT
True clock of low power differential pair for 96.00MHz DOT clock. No 50ohm
to GND needed. No Rs needed.
15 DOTC_96MHzLR OUT
Complementary clock of low power differential pair for 96.00MHz DOT clock.
No 50ohm resistor to GND needed. No Rs needed.
16 FSLB IN
3.3V tolerant input for CPU frequency selection. Refer to input electrical
characteristics for Vil_FS and Vih_FS values.
17 GNDSATA PWR Ground
in for the SATA out
uts
18 SATAT_LR/PCIeT_LR3 OUT
True clock of differential SATA pair. / True clock of differential PCI-Express pair
- selectable by FS(4:3) ; both are 0.8V differential push pull outputs with
inte
rated 33ohm series resistor.
19 SATAC_LR/PCIeC_LR3 OUT
Complementary clock of differential SATA pair. / Complementary clock of
differential PCI-Express pair - selectable by FS(4:3); both are 0.8V differential
ush
ull out
uts with inte
rated 33ohm series resistor.
20 VDDSATA PWR Su
l
for SATA clocks, 3.3V nominal
21 PCIeT_LR0 OUT
True clock of 0.8V differential push-pull PCI_Express pair with integrated
33ohm series resistor
22 PCIeC_LR0 OUT
Complementary clock of 0.8V differential push-pull PCI_Express pair with
inte
rated 33ohm series resistor
23 PCIeT_LR1 OUT
True clock of 0.8V differential push-pull PCI_Express pair with integrated
33ohm series resistor
24 PCIeC_LR1 OUT
Complementary clock of 0.8V differential push-pull PCI_Express pair with
inte
rated 33ohm series resistor
