XR215A Datasheet, PDF (25/32 Pages) Exar Corporation – Monolithic Phase-Locked Loop

XR-215A
C_c
20K
1K
Binary
Range Select
(Optional)
4K
Rx
-5V
+5V
0.1mF
U1
5 16 V_CC
6 Phase
4
Comp.
XR-215A
11
12 _VCO
10
V_EE
9 13 14
15
Op ₈
Amp
2 31 7
Cc
20K
VCO Output
Fo=NFs _Cc
10K
C₁
C₀
20K
C₁
Input
F=Fs
Level
Shifter
N
SN7493 or Equivalent
Figure 23. Circuit Connection For Frequency Synthesis
The circuit was designed to operate with commercially available monolithic programmable counter circuits using TTL
logic, such as MC4016, SN5493 or equivalent. The digital or analog tuning characteristics of the VCO can be used to
extend the available range of frequencies of the system, for a given setting of the timing capacitor C₀.
Typical input and output waveforms for N = 16 operation with f_s = 100kHz and f_o = 1.6MHz are shown in Figure 24.
Rev. 1.01
Figure 24. Typical Input/Output Waveforms for N=16
Top: Input (100kHz)
Bottom: VCO Output (1.6MHz)
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