FT4232HL-TRAY International Semiconductor Technologies, FT4232HL-TRAY Datasheet - Page 33

• Manufacturer Part Number: FT4232HL-TRAY
• Description: Specifications: Number of Channels: 4, QUART ; Lead Free Status: Lead Free ; RoHS Status: RoHS Compliant
• Manufacturer: International Semiconductor Technologies

6.3 Oscillator Configuration
Figure 6.5 Recommended FT4232H Crystal Oscillator Configuration.
Figure 6.5 illustrates how to connect the FT4232H with a 12MHz ± 0.003% crystal. In this case loading
capacitors should to be added between OSCI, OSCO and GND as shown. A value of 27pF is shown as the
capacitor in the example – this will be good for many crystals but it is recommended to select the loading
capacitor value based on the manufacturer’s recommendations wherever possible. It is recommended to
use a parallel cut type crystal.
It is also possible to use a 12 MHz oscillator with the FT4232H. In this case the output of the oscillator
would drive OSCI, and OSCO should be left unconnected. The oscillator must have a CMOS output drive
capability.
Table 6.1 OSCI Input characteristics
Parameter
Crystal
OSCI Vin
12MHz
FIn
Ji
27pF
27pF
Cycle to cycle jitter
Input Frequency
Input Voltage
Description
Copyright © 2010 Future Technology Devices International Limited
2
3
OSCI
FT4232H
OSCO
FT4232H QUAD HIGH SPEED USB TO MULTIPURPOSE UART/MPSSE IC
Minimum
2.97
Typical
< 150
3.30
12
Maximum
3.63
Document No.: FT_000060
Clearance No.: FTDI#78
Units
MHz
pS
Datasheet Version 2.2
V
+/- 30ppm
Conditions
33