Triac (Bidirectional Triode Thyristor)
TMA25x
Series
2
Absolute Maximum Ratings
Characteristic Symbol Notes Rating Units
Peak Repetitive Off-State Voltage V
DRM
TMA254Bx
R
GREF
=
∞
400 V
TMA256Bx
600 V
Peak Non-Repetitive Off-State Voltage V
DSM
TMA254Bx
R
GREF
=
∞
500 V
TMA256Bx
700 V
Isolation Voltage V
ISO
AC RMS applied for 1 minute between lead and case 2000 V
RMS On-State Current I
T(RMS)
50/60 Hz full cycle sine wave,
total Conduction angle (α+) + (α–) = 360°,
T
C
= 83°C
25 A
Surge On-State Current I
TSM
f = 60 Hz
Full cycle sine wave, peak value, non-repetitive,
initial T
J
= 125°C
263 A
f = 50 Hz 250 A
I
2
t Value for Fusing I
2
t Value for 50 Hz half cycle sine wave, 1 cycle, I
TSM
= 250 A 312 A
2
• s
Critical Rising Rate of On-State Current di/dt
I
T
= I
T(RMS)
× √2, V
D
= V
DRM
× 0.5, f ≤ 60 Hz, t
gw
≥ 100 μs,
t
gr
≤ 250 ns, I
gp
≥ 60 mA
25 A/μs
Peak Gate Current I
GM
f ≥ 50 Hz, duty cycle ≤ 10% 2 A
Peak Gate Power Dissipation P
GM
f ≥ 50 Hz, duty cycle ≤ 10% 5 W
Average Gate Power Dissipation P
GM(AV)
T
J
< T
J
(max)
0.5 W
Junction Temperature T
J
–40 to 125 ºC
Storage Temperature T
stg
–40 to 125 ºC
T1
T2
G
Terminal List Table
Number Name Function
1 T1 Main terminal, gate referenced
2 T2 Main terminal connect to signal side
3 G Gate control
Pin-out Diagram
Thermal Characteristics May require derating at maximum conditions
Characteristic Symbol Test Conditions Value Units
Package Thermal Resistance
(Junction to Case)
R
θJC
For AC 1.5 ºC/W
All performance characteristics given are typical values for circuit or
system baseline design only and are at the nominal operating voltage and
an ambient temperature, T
A
, of 25°C, unless oth er wise stated.
123
Selection Guide
Part Number
V
DRM
(V)
UL-Recognized
Component
Package Packing
TMA254B(I) 400 Yes
3-pin fully molded SIP with
heatsink mount
30 pieces per tube
TMA254B-L 400 –
TMA256B(I) 600 Yes
TMA256B-L 600 –
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
