MB1511 Fujitsu, MB1511 Datasheet - Page 9

• Manufacturer Part Number: MB1511
• Description: Serial Input PLL Frequency Synthesizer
• Manufacturer: Fujitsu

Phase comparator output waveforms are shown below.
Notes: Phase difference detection range: –2 to +2
5. Analog Switch
ON/OFF of analog switch is controlled by LE input signal. When the analog switch is ON, internal charge pump
output (D
When an analog switch is inserted between LP1 and LP2, faster lock up times is achieved to reduce LPF time
constant during PLL channal switching.
H (Changing the divide ratio of internal prescaler)
L (Normal operationg mode)
Spike appearance depends on charge pump characteristics. Also, the spike is output in order to diminish dead band.
When fr>fp or fr<fp, spike might not appear depending upon charge rump characteristics.
fr
fp
LD
D
O
O
) is connected to BISW pin. When the analog switch is OFF, BISW pin is set to high-impedance state.
fr > fp
(CONTROL SIGNAL LE)
H
LE
CHARGE
PUMP
fr = fp
D
O
Z
ANALOG
SW
LPF-1
fr < fp
L
BISW
fr < fp
LPF-2
Analog Switch
OFF
ON
fr < fp
VCO
MB1511
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