Hi, As I remember, I used to try 2.0 MHz crystal oscilator but it seemed PLL can't work at lower than 10MHz. I have just tested by changing OSC from now 10 MHz to 2 MHz with 6 time multiplier. The 1 ms interrupt timer changed to 1.8 ms, it should be 5 ms. So, I afraid it doesn't work at 4 MHz. Teera. --- In lpc2000@yahoogroups.com, "microbit" <microbit@c...> wrote: > Hi All, > > This might have come up before I think, but I can't seem to > readily find it in my LPC2000 folder. > > Has anyone ever tried supplying LPC2000 with an external 4 MHz > clock signal, to be used with PLL at higher clock rates ? > > Since it's a full swing Ext signal, I don't see any limitations, other > than the osc buffer ckty, which surely should handle that. > I'm thinking of multiplying up to 64 MHz cclk.. a tad too high. > And 8 X = 32 MHz is too low. > This is for LPC2119/29. > Space is critical and I need to save an SMT Xtal real estate wise. > > -- Kris
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Re: injecting an external 4 MHz clk into LPC2000, and using PLL - anyone done similar ?
2004-05-10 by tphatrapornnant