These Pololu products all use Silicon Lab’s CP2102 USB-to-UART bridge controller.
The Pololu USB-to-serial adapter is a tiny unit that makes it easy to connect a microcontroller project to a PC. You can connect the adapter directly to a microcontroller without an RS-232-to-TTL level converter. It is USB 2.0-compatible and will work with your existing programs that interface with a serial port.
The USB servo controller enables you to control up to sixteen hobby RC servos from your USB port. The servo controller has both the USB interface and a UART interface for communicating with small microcontrollers and other non-USB devices.
This compact programmer can program the Orangutan, Orangutan SV-168, Orangutan LV-168, and Baby Orangutan robot controllers, as well as the 3pi robot, through a USB connection. The on-board USB-to-serial adapter allows the unit to look like a serial AVRISP programmer to your programming software. The serial port TX and RX lines are connected to separate pads so that the programmer can also be used as a USB-to-serial adapter.