PSP serial adapter

Jim Paris <jim@jtan.com>

This level-shifting serial adapter for the PSP (and other devices) is based on the MAX3319E interface chip. This chip provides guaranteed 460kbps RS-232 compatible operation with a supply as low as +2.25V, making it a perfect choice for the +2.5V supply and logic interface on the PSP.

The board supports either a male or female DB9 connector in a DTE or DCE configuration, selectable with solder jumpers during assembly. Typically, to avoid the need for adapters and “null-modem” cables, female/DCE is used to connect the PSP to a PC, while male/DTE is used to connect the PSP to other devices like a GPS.

It was designed to fit comfortably inside a DB9 plastic hood. Four holes with 2.54mm spacing provide the power and data connections to the PSP.

Label Description PSP Pin

V Supply voltage, +2.25V to +3.0V 5, +2.5V

G Ground 2, Digital ground

IN Serial input to the adapter 3, TXD

OUT Serial output from the adapter 6, RXD

Label	Description	PSP Pin
V	Supply voltage, +2.25V to +3.0V	5, +2.5V
G	Ground	2, Digital ground
IN	Serial input to the adapter	3, TXD
OUT	Serial output from the adapter	6, RXD

A small number of these adapters are for sale. Please note that I haven't found a good source for the PSP cable, and so these are being sold with everything except the cable, as shown below.

The complete kit contains

MAX3319E
Five 0.1μF capacitors
Male (DTE) or female (DCE) DB9 connector, your choice
Printed circuit board, assembled with above components
DB9 plastic hood, with metal strain relief and fasteners

You need to obtain and solder your own cable to the adapter. My white cable came from a standard PSP headphone remote, and I took the short black one from a set of third-party headphones. Others have made their own cables and connectors for the PSP.

The cost is US $8 per adapter, and shipping is US $4 per order (USPS Priority Mail or USPS Global Priority Mail). Send money and a shipping address via PayPal to jim@jtan.com.