Si8440/41/42/45

Rev. 1.5

25

3. Errata and Design Migration Guidelines

The following errata apply to Revision C devices only. See "5. Ordering Guide" on page 27 for more details. No

errata exist for Revision D devices.

3.1. Enable Pin Causes Outputs to Go Low (Revision C Only)

When using the enable pin (EN1, EN2) function on the 4-channel (Si8440/1/2) isolators, the corresponding output

pin states (pin = An, Bn, where n can be 1…4) are driven to a logic low (to ground) when the enable pin is disabled

(EN1 or EN2 = 0). This functionality is different from the legacy 4-channel (Si8440/1/2) isolators. On those devices,

the isolator outputs go into a high-impedance state (Hi-Z) when the enable pin is disabled (EN1 = 0 or EN2 = 0).

3.1.1. Resolution

The enable pin functionality causing the outputs to go low is supported in production for Revision C of the Si844x

devices. Revision D corrects the enable pin functionality (i.e., the outputs will go into the high-impedance state to

match the legacy isolator products). Refer to the Ordering Guide sections of the data sheet(s) for current ordering

information.

3.2. Power Supply Bypass Capacitors (Revision C and Revision D)

When using the Si844x isolators with power supplies > 4.5 V, sufficient VDD bypass capacitors must be present on

both the VDD1 and VDD2 pins to ensure the VDD rise time is less than 0.5 V/µs (which is > 9 µs for a > 4.5 V

supply). Although rise time is power supply dependent, > 1 µF capacitors are required on both power supply pins

(VDD1, VDD2) of the isolator device.

3.2.1. Resolution

For recommendations on resolving this issue, see "2.4.1. Supply Bypass" on page 22. Additionally, refer to "5.

Ordering Guide" on page 27 for current ordering information.

3.3. Latch Up Immunity (Revision C Only)

Latch up immunity generally exceeds ± 200 mA per pin. Exceptions: Certain pins provide < 100 mA of latch-up

immunity. To increase latch-up immunity on these pins, 100

 of equivalent resistance must be included in series

with all of the pins listed in Table 14. The 100

 equivalent resistance can be comprised of the source driver's

output resistance and a series termination resistor. The Si8441 is not affected when using power supply voltages

(VDD1 and VDD2) < 3.5 V.

3.3.1. Resolution

This issue has been corrected with Revision D of the device. Refer to “5. Ordering Guide” for current ordering

information.

Table 14. Affected Ordering Part Numbers (Revision C Only)

Affected Ordering Part Numbers*

Device

Revision

Pin#

Name

Pin Type

SI8440SV-C-IS/IS1, SI8441SV-C-IS/IS1,

SI8442SV-C-IS/IS1

C

6

A4

Input or Output

10

EN2

Input

14

B1

Output

SI8445SV-C-IS/IS1

C

6

A4

Input

14

B1

Output

*Note: SV = Speed Grade/Isolation Rating (AA, AB, BA, BB).