I've been trying to find a replacement for the BeagleBoard-Xm parts Q1 and Q2 transistor arrays. (Part #XP0421400L) Apparently this particular part is obsolete and no longer available. XP0421100L is the suggested replacement part, but is also now obsolete but with stock available. Unfortunately, the specification for the R2 resistor is 10K, where the original part's R2 is specified at 47K.
Toshiba part RN1907 was also recommended as a replacement, but the factory has never produced any of those particular chips. They are willing to build a minimum order, but that will be difficult unless someone wants the 2900 or so extra parts?
Does anyone know a suitable replacement part that's available? I've not been able to identify the required subset of the specifications that are required for the -Xm board's usage. I've listed the specifications for the part below.
The specifications from Digikey report the following for the specified part. (Table from http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=XP0421400LTR-ND)
Category: Discrete Semiconductor Products
Family: Transistors (BJT) - Arrays, Pre-Biased
Series: Transistor Type 2 NPN - Pre-Biased (Dual)
Current: 100mA # Collector (Ic) (Max)
Voltage: 50V # Collector Emitter Breakdown (Max)
Resistor R1: 10K # Base (R1) (Ohms)
Resistor R2: 47K # Emitter Base (R2) (Ohms)
DC Current: 80 @ 5mA, 10V # Gain (hFE) (Min) @ Ic, Vce
Vce Saturation: 250mV @ 300µA, 10mA # (Max) @ Ib, Ic
Current Cutoff: 500nA # Collector Cutoff (Max)
Frequency: 150MHz # Transition
Power: 150mW # Max
Mounting Type: Surface Mount
Package / Case: SC-70-6, SC-88, SOT-363