45 |
P a g e
a) Punch-through IGBT: Heavily doped
n buffer layer
➔
less switching time
b) Non-Punch-through IGBT: Lightly
doped n buffer layer
➔
greater
carrier lifetime
➔
increased
conductivity of drift region
➔
reduced on-state
voltage drop
(Note:
➔
means implies)
Figure: 1. 41. Equivalent diagram of IGBT
Figure: 1. 42. Simplified Equivalent diagram of IGBT
46 |
P a g e
Figure: 43. Equivalent diagram of IGBT
Based on this circuit diagram given in Fig. 43, forward characteristics and transfer
characteristics are
obtained which are given in Fig. 44 and Fig. 45. Its switching characteristic is also shown in Fig. 45.
Figure: 1. 44. Forward characteristics of IGBT