cxa3516r Sony Electronics, cxa3516r Datasheet - Page 49

• Manufacturer Part Number: cxa3516r
• Description: 3-channel 8-bit 165msps A/d Converter Amplifier Pll
• Manufacturer: Sony Electronics

• VCO frequency dividers (DIV 1, 2, 4, 8)
• Programmable counter
• Clock output
The oscillation frequency of the VCO can be divided to 1/1, 1/2, 1/4, or 1/8 according to a control register setting.
Depending on the combination of the VCO oscillation frequency and VCO frequency divider, the Point B
clock frequency covers an operating range of 5MHz to 165MHz. The matrix of the VCO frequency divider
setting is as follows.
The clock frequency at Point B is divided and a programmable counter output signal is generated.
The frequency division ratio can be set optionally by using a 12-bit control register. This is determined by
using lower order 3 bits and upper order 9 bits in the following formula.
After the set value for the frequency division ratio is changed, that set value is loaded into the programmable
counter when the output value of the programmable counter becomes "all 0".
When the input polarity of the SYNC signal is positive, the clock output is synchronized to the rising edge of
the SYNC signal and is available as complementary signals CLK (Pin 99) and XCLK (Pin 98). The delay
time of the clock output can be varied in the range of 1/32CLK to 64/32CLK by using a control register (see
PLL timing diagram). Although the clock output can be turned off independently by using a control register,
it cannot be set to high impedance. The operational frequency of the clock is up to 100MHz.
[VCO Frequency Divider Setting Matrix]
Register 0
Register 1
Register
No.
Register: DIV 1, 2, 4, 8 Bit1
Register: DIV 1, 2, 4, 8 Bit0
Clock frequency: DIV setting value
Frequency division ratio = (m + 1)
Register: CLK Enable, XCLK Enable
14MHz to 40MHz: 1/4
40MHz to 80MHz: 1/2
80MHz to 120MHz: 1/1
m: 9 bits (VCO DIV Bit 3 to 11)
n: 3 bits (VCO DIV Bit 0 to 2)
Counter frequency
5MHz to 14MHz: 1/8
Clock output status
VCODIV1
VCODIV2
Register
Name
Data7
MSB
m4
1/1
0
0
Data6
8 + n
m3
1/2
0
1
Data5
m2
– 49 –
Off
0
1/4
1
0
Data4
m1
1/8
1
1
Data3
m0
m8
On
1
Data2
m7
n2
Data1
m6
n1
Data0
LSB
m5
n0
CXA3516R