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CHT-CG-050 Datasheet, PDF (1/9 Pages) List of Unclassifed Manufacturers – Versatile High Temperature Clock Generator
CISSOID The SOI design Specialist
CHT-CG-050
Preliminary datasheet
Version 0.4 (08/2005)
Versatile High Temperature Clock Generator
General Description
The CHT-CG-050 is a versatile High-
Temperature crystal clock generator with
extended functional capabilities. The chip
features a programmable crystal oscillator
driver with an enable/disable control sig-
nal, an external clock input, a programma-
ble divider chain and a programmable
strength three-state output buffer. Using
an external crystal, it is intended to provide
reliable precision performance throughout
the -30 to +225°C temperature range for
supply voltages between 3V and 5V.
The CHT-CG-050 can operate with crys-
tals from 1MHz to 50MHz. The output fre-
quency can be selected by means of a
programmable divider, providing division
factors of one, two, four and eight. The
programmability of the crystal driver allows
working with a wide range of crystals. A
crystal driver enable pin (/XtalEn) is in-
cluded for extremely low power applica-
tions, as well as an output enable pin
(/OE). In applications requiring only a pre-
cision divider chain, where an external
clock source is already present, the crystal
driver may be bypassed by means of in-
puts ExtClkIn and ExtClkEn.
Features
• 3V to 5V power supply
• Qualified from -30 to +225°C (Tj)
• Operational up to +250°C (Tj)
• Two input sources: crystal (1 to 50
MHz), external clock (DC to 50MHz)
• Operation from 32.768kHz crystals
• Programmable frequency divider: fin,
fin/2, fin/4 and fin/8
• Programmable crystal driver and out-
put driver strength
• Available in several standard pack-
ages or as die
Applications
• Well logging, Automotive, Aeronautics
& Aerospace
• Precision timing
Pin Description
C1_10pF Built-in capacitors with a
C1_20pF common terminal connected
C2_10pF to Vss.
C2_20pF
DIV_0
DIV_1
Inputs to set
factor.
TRUTH TABLE
DIV_1
DIV_0
0
0
0
1
1
0
1
1
the division
Factor
1
2
4
8
DRI_0
DRI_1
Inputs to set
buffer strength.
TRUTH TABLE
DRI_1
DRI_0
0
0
0
1
1
0
1
1
the output
Strength
8mA
16mA
24mA
32mA
ExtClkEn When driven HIGH, opera-
tion from the external clock
source is selected.
ExtClkIn Input for an external clock
source.
FOUT
Output signal.
/OE
When driven LOW, output is
enabled, When driven
HIGH, output is at high im-
pedance.
R2
Terminal of a 200Ω resistor.
The other terminal of this
resistor is connected to X2.
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