- on Computer/Software/Internet
- Published in issue 3/2005 on page 0
Serially Programmable Crystal Oscillator
Compact and universal
The right crystal controlled frequency at the right time: With this DIP outline oscillator there’s no need to wait for a special crystal to be made up. You can program its frequency precisely using the RS232 port of your PC. Low phase noise is a feature that makes this PLL oscillator suitable for demanding RF applications also.
This multipurpose clock generator circuit uses the CY27EE16 programmable oscillator of the CyberClock family of devices from
R1 = 1k?5
R2-R8 = 220?
R9 = 10k?
R10,R11 = 1k?
C1 = 1µF 16V, radial
C2,C3 = 22pF
C4 = 100nF
D1-D34 = LED, 3mm, low current, red
T1 = BC547
IC1 = ULN2803
IC2 = 4023
IC3 = AT90S2313-10PC, programmed, order code 030410-41
S1 = on/off switch, one contact
S2-S8 = pushbutton, PCB mount, 1 contact, 5mm, e.g., T60 (Conrad Electronics # 700479)
X1 = 4MHz quartz crystal
BZ1 = 5VDC (active) buzzer
BT1 = 2 x penlight (AA) battery with holder
Enclosure, e.g., Hammond type 1591DTRD (150 x 46 x 84mm)
PCB, ref. 030410-1, from The PCBShop