Today we’ll be taking a look at the D-Link Wireless N300 ADSL2+ Modem Router (DSL-2750B), an ADSL2+ wireless N router with 4x 10/100 network ports, a USB port for device/printer sharing and dual antennas.
4 screws later and we’re in.
We’ve got quite a few 25V 1000uF caps but they are CapXon branded ones and 2x Lelon 10V 470uF caps too. The antennas are soldered directly to the PCB and glued down, one of them has an RF choke and they’ve skipped the shielded can on the Wifi chip.
There is a header near an inductor which could be a serial header and instead of placing a thermal pad or paste on the main chip they’ve just placed glue and the heatsink on top, eh I guess they wanted to save cost.
Interestingly there are a few small spark gaps for the USB pins. For the DSL line driver side of things they’ve gone with through-hole caps instead of SMD caps like most modern routers do, I guess space wasn’t too much of a concern. For the power side of things, there’s a TY34063 step down (MC34063 variant), an Fiti FR9886 step down plus 2x smaller 6 pin step down DC-DC converters too. The PCB date code is 46th week of 2012.
1. Broadcom MIPS32 320MHz SoC
Under the heatsink we’ve got the main chip, unfortunately not too much is available on it – EEMBC link.
BCM63281
2. Winbond 512Mbit DDR2 SDRAM
W9751G6KB-25
3. Broadcom 802.11 b/g/n Wifi
Running with a 20MHz crystal, not much info on this chip
BCM43225
4. MXIC 64Mbit Flash
25L6406E
5. Broadcom ADSL2+ Line Driver
BCM6301
And that’s all.
