IC-SP-06027 R1
1. Overview
1-1. Dielectric isolation (DI)
Hitachi Intelligent Power IC
A logical device and a power-switching device can be integrated in a
single chip.
No mutual interference occurs, not only between devices but also
between device and board.
The Hitachi high-voltage monolithic IC is an intelligent power IC, developed based on a unique dielectric isolation
technology (DI). It is structured that there be no latch-up between devices and between device and board, and that
an IC can be made so a high-dielectric-strength, large-current output circuit is mixed with a logical circuit. The ICs
can be made smaller than conventional discrete boards and hybrid ICs.
Latch-up-free IC offers wider range of applications.
The Hitachi high-voltage monolithic IC developed with dielectric isolation technology are such that the devices are
isolated with SiO
2
layers in between, unlike P-N junction isolation. In consequence, it can remain latched-up free
even under high-temperature, large-current, high-noise, and other severe conditions. This technology also enables
them to be extremely flexible in circuit designing and thus to meet more customer requirement.
Aluminum wire
Dielectric isolation
N
P
N
SiO
2
Single crystal silicon
Poly silicon
SiO
2
(Insulator separation layer)
Aluminum wire
N
P-N junction isolation
P+
N
SiO
2
P
N
P+
N
N
Single crystal silicon
P type silicon
Depletion layer
(Insulator separation layer)
Fig. 1-1. Dielectric isolation and P-N junction isolation
-1-