U2100B Datasheet, PDF (5/14 Pages) TEMIC Semiconductors – Timer Control for Triac and Relay

U2100B
3.1 Mode Selection Pin 4 and Supply Voltage Pin 2
The operational modes can be selected by the external voltage at the synchronous input pin 4
(clamping). The mode selection determines the current requirement of the relay's or triac's driver
stage and hence the selection of the supply voltage.
3.2 Zero Voltage Switch Operation (Figure 3-3 on page 6)
Selection condition:
V₄ = internal synchronous limitation, without external clamping
R₁ ≈
0.85
V_{-----M-----–-----}V_----S-
2 I_tot
I_tot = I_S + I_p + I_X
where:
I_S
= Supply current of the IC without load
I_P
= Average trigger current I_G
I_X
= External circuit current requirement
V_M
= Mains voltage
Required firing pulse width t_p
t_p
=
2_{-ω- arcsin}
⎛
⎝
-^IP-^L----^×-_×-----^V-----^M₂--_⎠⎞
where:
I_L
P
= Triac latching current
= Power at load Z
R_sync[kΩ] ≈
V_-----M----[_--V_----]_---×_----------2_---s_----i_-n_-----(_---ω_----×_------t_--p---[_-s_---]_--)_{----–-----}0_---._--7_{- – 176}
1.8 × 10^-2
5
4769C–INDCO–07/05