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SMD-00191 Rev D

Subject to Change Without Notice

PFD1K

Control Logic Circuitry:

The same circuitry is used for all control lines: A[0:3], R[0:6], V[0:6] and POL. A control pin left open

defaults to logic 0.

Analog Amplitude Controls:

As was previously mentioned, VADJ can be used for fine tuning the charge pump current. Maximum

current is achieved by setting VADJ to VCC. Similarly, the amplitudes of the prescaler outputs at

DRO and DVO can be controlled with analog voltages VADR and VADV, respectively. As with VADJ,

setting VADR and VADV to VCC results in maximum output amplitude.

Simplified Control Logic Input

Logic Level

Minimum

Typical

Maximum

1 (High)

VCC-1.3 V

VCC

VCC

0 (Low)

VEE

VEE

VEE+0.8 V

Table 1: Control Voltages (LVTTL Compatible)