XR-2207 Datasheet, PDF (12/24 Pages) Exar Corporation – Voltage-Controlled Oscillator

XR-2207
Single Supply Operation
The circuit should be interconnected as shown in
Figure 14A or Figure 14B for single supply operation. Pin
12 should be grounded, and pin 11 biased from V_CC
through a resistive divider to a value of bias voltage
between V⁺/3 and V⁺/2. Pin 10 is bypassed to ground
through a 1µF capacitor.
For single supply operation, the DC voltage at pin 10 and
the timing terminals (pins 4 through 7) are equal and
approximately 0.6V above V_B, the bias voltage at pin 11.
The logic levels at the binary keying terminals are
referenced to the voltage at pin 10.
V_CC
CB ^VCC
C
12
3
V+
8A
Keying Inputs
CB ^{9 B}
10
GND
C1
C2
13
SWO
XR-2207
14
TWO
11
BIAS
R 1 R 2 R 3 R 4 V-
4 5 6 7 12
CB = Bypass Cap
R1 R2 R3 R4
RL
Square Wave
Output
Triangle Wave
Output
V_CC
5.1K
3.9K
Rev. 2.02
A. General Case
V_CC
CB V_CC
C
12
3
V+
8
A
9B
10
GND
C1
C2
XR-2207
13
SWO
14
TWO
11
BIAS
R 1 R 2 R 3 R 4 V-
CB
4 5 6 7 12
RL
Square Wave
Output
Triangle Wave
Output
V_CC
5.1K
3.9K
R3
f=1/R3<C
CB = Bypass Cap
B. Single Frequency
Figure 14. Single Supply Operation
12