Toshiba T1900 Series
- For more information, see this article's corresponding Wikipedia page: Toshiba_T_series.
| Preliminary Information | |
|---|---|
| Release Year | 1993/1994 |
| Leak Risk | High |
| Batteries | 3 Batteries:
Main battery: Nickel Metal Hydride 12 V 2,400mAH Backup battery: AA sized Nickel Metal Hydride 1.2 V 1,100mAH RTC battery: 2032 rechargeable Lithium-Vanadium 3.0 V 50mAH |
| Destructive Entry | No |
| Hardware Specifications | |
| CPU | 80486 CPU, including the SX-20, SX-33, DX2-40 and DX2-50 |
| Memory Capacity | 4Mb, expandable up to 20Mb via optional Memory Card |
| Power Requirements | |
| Input Voltage | 18V DC |
| Current (Amps) | 1.1 or 1.7A |
Known Issues
Laptop won't power on
The Toshiba T1950 Laptop is known not to power on due to bad caps on the power board, the lower of the two boards in the laptop. When the on button is pressed, it lights up, but immediately turns off.
Causes
- Bad or leaky caps
Solutions
- Replace the Caps and clean the board
Disassembly Notes
Almost all the screw are the same thread (m2.5), but vary in length. There are some M2 screws in the display assembly.
The service manual has a complete guide on how to disassemble the laptop (see the link below).
Original Parts
Lower PCB
- C526, C527, C528 are surface mount caps, can be replaced with MLCC caps.
- C523 and C208 are on the underside of the PCB
- C523 and C208 are surface mount and can be replaced with MLCC caps
- See the service manual for locations, or the Vogons post about this (both linked below)
| RefDes | Qty | Capacitance | Voltage | Mount | Diameter/Size | Height | Lead Spacing | Temp | Type | Brand | Series |
|---|---|---|---|---|---|---|---|---|---|---|---|
| C504 | 1 | 470 µF | 25 | Through Hole | 10mm? | 105 °C | Electrolytic | ||||
| C509 | 1 | 2200 µF | 6.3 | Through Hole | 12.75mm | 20mm | 105°C | Electrolytic | |||
| C518, C520 | 2 | 56 µF | 16 | Through Hole | 6.5mm | 7.5mm | 105°C | Electrolytic | |||
| C516, C521 | 2 | 120 µF | 16 | Through Hole | 6.5mm | 11.5mm | 105°C | Electrolytic | |||
| C511 | 1 | 1000 µF | 6.3 | Through Hole | 10.5mm | 10mm | 105°C | Electrolytic | |||
| C507, C513, C515 | 3 | 220 µF | 10 | Through Hole | 6.5mm | 10mm? | 85°C | Electrolytic | |||
| C526, C527, C528, C523* | 4 | 10 µF | 6.3 | SMD | |||||||
| C208* | 1 | 33 µF | 6.3 | SMD |
* On the underside of the board
Replacement Parts
Lower PCB Top Side
| RefDes | Qty | Compatible Part Number | Order Links |
|---|---|---|---|
| Digikey | |||
If parts are not available or different selection is preferred, you can use the values in the Original Parts section to perform a parametric search.
Related Links
Vogons forum post about the issues with the power board
T1900 Maintenance Manual at minuszerodegrees.net