STW81101AT STMicroelectronics, STW81101AT Datasheet - Page 35

• Manufacturer Part Number: STW81101AT
• Description: IC SYNTHESIZER MULTI RF 28VFQFPN
• Manufacturer: STMicroelectronics
• Type: Frequency Synthesizer (RF)r

Specifications of STW81101AT

• Pll: Yes
• Input: Clock, Crystal
• Output: Clock, Crystal
• Number Of Circuits: 1
• Ratio - Input:output: 3:2
• Differential - Input:output: No/No
• Frequency - Max: 4.4GHz
• Divider/multiplier: Yes/No
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-VFQFN, 28-VFQFPN
• Frequency-max: 4.4GHz
• Number Of Elements: 1
• Pll Input Freq (min): 10MHz
• Pll Input Freq (max): 200MHz
• Operating Supply Voltage (typ): 3.3V
• Operating Temp Range: -40C to 85C
• Package Type: VFQFPN
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 3.6V
• Operating Temperature Classification: Industrial
• Pin Count: 28
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

STW81101
6.4
6.4.1
VCO calibration procedure
Calibration of the VCO center frequency is activated when the SERCAL bit (CALIBRATION
register bit[6]) is set to 1.
To program the device properly while ensuring VCO calibration, perform the following steps
before every channel change:
1.
2.
The maximum allowed PFD frequency (F
higher than 1 MHz, perform the following additional steps:
●
●
VCO calibration auto-restart feature
The VCO calibration auto-restart feature can be enabled in two steps:
1.
2.
Program all the registers using a multi-byte write sequence with the desired settings
(functional mode, B and A counters, R counter, VCO amplitude, charge pump,
prescaler modulus), and all the bits of the CALIBRATION register (05H) set to 0.
Program the CALIBRATION register using a single-byte write sequence (subaddress
05H) with the SERCAL bit set to 1.
Perform all the steps of the calibration procedure, making sure to program the desired
VCO frequency with proper settings for the R, B and A counters so that F
Program the device with the desired VCO and PFD frequency settings according to
step 1) above.
set the desired frequency ensuring VCO calibration as described above (section 6.4)
program the FUNCTIONAL_MODE register (sub-address 00H) using a single-byte
write sequence with the CAL_AUTOSTART_EN bit set to '1' while keeping unchanged
the others.
PFD
) during calibration is 1 MHz; if you want a F
I
2
C bus interface
PFD
is ≤ 1 MHz.
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PFD