UM10139

Philips SemiconductorsVolume 1UM10139Chapter 3: System Control BlockLPC2141/2/4/6/8LPC2141/2/4/6/8X1X2X1X2LC < = >C C LC PC X1C X2ClockXtalR Sa) b) c)Fig 6.Oscillator modes and models: a) slave mode of operation, b) oscillation mode ofoperation, c) external crystal model used for C X1 / X2 evaluationTable 7:Recommended values for C X1/X2 in oscillation mode (crystal and externalcomponents parameters)Fundamentaloscillation frequencyF OSCCrystal loadcapacitance C LMaximum crystalseries resistance R SExternal loadcapacitors C X1 , CX21 MHz - 5 MHz 10 pF NA NA20 pF NA NA30 pF < 300 Ω 58 pF, 58 pF5 MHz - 10 MHz 10 pF < 300 Ω 18 pF, 18 pF20 pF < 300 Ω 38 pF, 38 pF30 pF < 300 Ω 58 pF, 58 pF10 MHz - 15 MHz 10 pF < 300 Ω 18 pF, 18 pF20 pF < 220 Ω 38 pF, 38 pF30 pF < 140 Ω 58 pF, 58 pF15 MHz - 20 MHz 10 pF < 220 Ω 18 pF, 18 pF20 pF < 140 Ω 38 pF, 38 pF30 pF < 80 Ω 58 pF, 58 pF20 MHz - 25 MHz 10 pF < 160 Ω 18 pF, 18 pF20 pF < 90 Ω 38 pF, 38 pF30 pF < 50 Ω 58 pF, 58 pF25 MHz - 30 MHz 10 pF < 130 Ω 18 pF, 18 pF20 pF < 50 Ω 38 pF, 38 pF30 pF NA NA© Koninklijke Philips Electronics N.V. 2005. All rights reserved.User manual Rev. 01 — 15 August 2005 19