Table 26. Usb Differences Between Stm32L1 Series And Stm32L4 Series - ST STM32L1 Series Application Note

AN4612
4.18 USB
The STM32L4 and STM32L1 Series implement different USB peripherals.
While STM32L1 Series implements a USB FS device interface, the STM32L4 Series
implements a USB OTG FS interface. on Cat. 2 devices and a USB FS device only on Cat.
4 devices.
Most features supported by STM32L1 Series are also supported by STM32L4 Series.
The key differences are listed below.

Table 26. USB differences between STM32L1 Series and STM32L4 Series

USB
Universal serial bus Revision 2.0.
FS mode:
– 1 bidirectional control endpoint
– 7 IN endpoints (Bulk, Interrupt, Isochronous)
– 7 OUT endpoints (Bulk, Interrupt,
Features
Isochronous).
USB internal connect/disconnect feature with an internal pull-up resistor on the USB D+
(USB_DP) line.
Mapping APB1
512bytes (endpoint buffers and buffer
Buffer memory
descriptors structure).
USB suspend and resume
Low-power
modes
STM32L1 Series
NA
NA
NA
DocID027094 Rev 3
Peripheral migration
STM32L4 Series
Universal serial bus Revision 2.0, including link
power management (LPM) support
Full support for the USB on-the-go (USB OTG).
(except on Cat. 4 devices)
FS mode:
– 1 bidirectional control endpoint
– 5 IN endpoints (Bulk, Interrupt, Isochronous)
– 5 OUT endpoints (Bulk, Interrupt,
Isochronous).
Cat. 4 devices:
identical to STM32L1 Series
Attach Detection Protocol (ADP) (except on
Cat. 4 devices)
Battery Charging Detection (BCD)
Independent V power supply allowing
DDUSB
lower V while using USB.
DDCORE
APB1 (Cat. 4 devices)
AHB2 (Cat. 2 devices)
1.25Kbytes data FIFOs
Management of up to 6 Tx FIFOs (1 for each IN
end point) + 1 Rx FIFO
(except on Cat. 4 devices)
USB suspend and resume.
Link power management (LPM) support.
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