2N7640-GA Datasheet, PDF (6/10 Pages) GeneSiC Semiconductor, Inc. – Normally – OFF Silicon Carbide Junction Transistor

2N7640-GA
Section V: Driving the 2N7640-GA
The 2N7640-GA is a current controlled SiC transistor which requires a positive gate current for turn-on and to remain in on-state. It may be
driven by different drive topologies depending on the intended application.
Table 1: Estimated Power Consumption and switching frequencies for various Gate Drive topologies.
Drive Topology
Gate Drive Power Switching
Consumption
Frequency
Simple TTL
High
Low
Constant Current
Medium
Medium
High Speed – Boost Capacitor
Medium
High
High Speed – Boost Inductor
Low
High
Proportional
Lowest
Medium
Pulsed Power
Medium
N/A
A: Simple TTL Drive
The 2N7640-GA may be driven by 5 V TTL logic by using a simple current amplification stage. The current amplifier output current must meet
or exceed the steady state gate current, IG,steady, required to operate the 2N7640-GA. An external gate resistor RG, shown in the
Figure 18 topology, sets IG,steady to the required level which is dependent on the SJT drain current ID and DC current gain hFE, RG may be
calculated from the equation below. The value of VEC,sat can be taken from the PNP datasheet, a partial list of high-temperature PNP and NPN
transistors options is given below. High-temperature MOSFETs may also be used in the topology.
Inverting _{5 V}
Current
Boost
Stage
TTL
Gate Signal
PNP
IG,steady
SiC SJT
D
G
0/5V
TTL i/p
inverted
0/5V
TTL o/p
R_G
S
NPN
Figure 18: Simple TTL Gate Drive Topology
Table 2: Partial List of High-Temperature BJTs for TTL Gate Driving
BJT Part Number
Type
Tj,max (°C)
PHPT60603PY
PHPT60603NY
2N2222
2N6730
2N2905
2N5883
2N5885
PNP
175
NPN
175
NPN
200
PNP
200
PNP
200
PNP
200
NPN
200
Dec 2014
http://www.genesicsemi.com/high-temperature-sic/high-temperature-sic-junction-transistors/
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