UMFT313EV FTDI, UMFT313EV Datasheet - Page 18

• Manufacturer Part Number: UMFT313EV
• Description: Interface Development Tools FT313H Hi-Speed USB Host Dev Module
• Manufacturer: FTDI
• Type: USBr

Specifications of UMFT313EV

• Rohs: yes
• Product: Development Boards
• Tool Is For Evaluation Of: FT313H
• Interface Type: USB
• Operating Supply Voltage: 5 V
• For Use With: FT313H

4.9 Power management
4.9.1 Power up and reset sequence
When VCC(I/O) and VCC(3V3) are on, an internal regulator will power on with VCC(3V3) on.
An internal POR pulse will be generated during the regulator power on, so that internal circuits
are in reset state until the regulator power is stable.
4.9.2 Power supply
Power supplies are defined in Table 4.4.
Table 4-4 Power supply
4.9.3 ATX reference voltage
The ATX circuit provides a stable internal voltage reference (+1.2V) to bias the analog
circuitry. This circuit requires an accurate external reference resistor. Connect 12kΩ±1%
resistor between pins RREF and GND.
4.9.4 Power modes
Power management configuration defined in Table 4.5.
For each bit description, see CONFIG register.
Table 4-5 power management configuration
4.9.4.1 Operation mode
All power supplies are present. Host controller is active.
4.9.4.2 Suspend mode
All power supplies are present. Host controller goes to USB suspend.
The steps for the host suspend are as follows:
VCC(3V3)
VCC(I/O)
Symbol
1. Clear the RS bit of the USBCMD register to stop the host controller from executing
2. Set the PO_SUSP bit of the PORTSC register to force the host controller to go into
3. Disable OSC_EN, PLL_EN and HC_CLK_EN bits of the CONFIG register to save power.
4. Clear the U_SUSP_U bit of the EOTTIME register to put the chip into suspend mode.
OSC_EN
schedule.
suspend.
1
0
1.8V, or 2.5V, or 3.3V
Copyright © 2012 Future Technology Devices International Limited
Typical
3.3V
PLL_EN
1
0
Supply for digital I/O pad
Supply for chip
FT313H USB2.0 HS Host Controller Datasheet Version 1.1
HC_CLK_EN
1
0
Description
Operation mode
Suspend mode
Description
Document No.: FT_000589
Clearance No.: FTDI# 318
18