SI861X Datasheet, PDF (5/38 Pages) Silicon Laboratories – Low-Power Single and Dual-Channel Digital Isolators

Si861x/2x Data Sheet
Device Operation
3. Device Operation
Device behavior during start-up, normal operation, and shutdown is shown in Figure 3.1 Device Behavior during Normal Operation on
page 5, where UVLO+ and UVLO– are the respective positive-going and negative-going thresholds. Refer to the following table to
determine outputs when power supply (VDD) is not present.
Table 3.1. Si86xx Logic Operation
V_I Input^{1, 2} VDDI State^{1, 3, 4} VDDO State^{1, 3, 4} V_O Output^{1, 2}
Comments
H
P
P
H
Normal operation.
L
P
P
L
X⁵
UP
P
L⁶
Upon transition of VDDI from unpowered to powered, V_O re-
H⁶
turns to the same state as V_I in less than 1 µs.
X⁵
P
UP
Undetermined Upon transition of VDDO from unpowered to powered, V_O re-
turns to the same state as V_I within 1 µs.
Note:
1. VDDI and VDDO are the input and output power supplies. VI and VO are the respective input and output terminals.
2. X = not applicable; H = Logic High; L = Logic Low; Hi-Z = High Impedance.
3. “Powered” state (P) is defined as 2.5 V < VDD < 5.5 V.
4. “Unpowered” state (UP) is defined as VDD = 0 V.
5. Note that an I/O can power the die for a given side through an internal diode if its source has adequate current.
6. See Ordering Guide for details. This is the selectable fail-safe operating mode (ordering option). Some devices have default out-
put state = H, and some have default output state = L, depending on the ordering part number (OPN). For default high devices,
the data channels have pull-ups on inputs/outputs. For default low devices, the data channels have pull-downs on inputs/outputs.
silabs.com | Smart. Connected. Energy-friendly.
Rev. 1.6 | 4