Dual Interposer Overview
Taiwan Patent No. 121834
is an FR4 PCM (Personal Computer Module) design, which connects
two 360-lead CBGA PowerPC microprocessors and a 288-pin PGA.
It structures individual backside L2 cache devices, and integrates
MPC750 and MPC7400 (MPC7410)** bus interface for symmetric
multiprocessor architecture. The Dual Interposer provides
1M / 4M bytes with 150MHz on L2 cache interface and 100 /
133 MHz 60X system bus.
The additional power
supply filtering on the processor module consists of a PLL
voltage supply (AVdd) which is filtered on the PGA PCM, and
a Core voltage supply (Vdd) which is filtered on PCM. The
former is close to the processor and improves the noise immunity,
and the latter can reduce voltage variations.
The PCM signals
determine both the selection of processor voltage and the
self-identification of module type. They can encode and control
the power supply modules directly. Furthermore, a Four-voltage-ID-pins
design has the ability to select operating core voltage from
1.3V to 3.5V and to encode in order to match industry-standard
power-controllers. For encoding simple modules, there is another
3-pin design available.