F1912 Datasheet

R35DS0055EU0100 Rev.1.00

Nov 10, 2022

Page 18

Item #

Part Reference

QTY

DESCRIPTION

Mfr. Part #

Mfr.

9

J5, J7

2

CONN HEADER VERT SGL 2 X 1 POS

GOLD

961102-6404-AR

3M

10

J8

1

CONN HEADER VERT SGL 4 X 1 POS

GOLD

961104-6404-AR

3M

11

J6

1

CONN HEADER VERT SGL 8 X 1 POS

GOLD

961108-6404-AR

3M

12

J2, J3, J4

3

Edge Launch SMA (0.250 inch pitch ground,

round)

142-0711-821

Emerson Johnson

13

U1

1

SWITCH 8 POSITION DIP SWITCH

KAT1108E

E-Switch

14

U2

1

DSA

F1912Z

IDT (Renesas)

15

1

Printed Circuit Board (Rev 01)

F1953S EVKit Rev 01

IDT (Renesas)

16

Bill Of Material (Rev 01)

6.

Applications Information

6.1

F1912 Digital Pin Voltage and Resistance Values (Pins Not Connected)

The following table lists the resistance between various pins and ground when no DC power is applied. When

the device is powered up with +5 Volts DC these same pins should have the measured voltage to ground.

Pin

Name

DC Voltage (volts)

Resistance (ohms)

13

VMODE

2.5V

100 kΩ pullup resistor to internally regulated 2.5 V

3, 4, 5

DATA, CLK, LE

2.5V

100 kΩ pullup resistor to internally regulated 2.5 V

6.2

Logic Voltage Applied before Power Supply

Due to on-chip ESD protection circuitry, the VDD supply voltage is required to be present before the logic

voltages can be applied to the logic pins (VMODE, DATA, LE, CLK, D[5:0]). If in the application this is not possible,

then a series resistor of 3kΩ needs to be added in line with each of the logic pins, D0-D3. The other logic pins

(VMODE, DATA, LE, CLK, D4, D5) already have a significant resistor value per the Bill Of Material (BOM). This

resistor limits the current into the logic pin to a safe level when VDD is not present. The resistor should be placed

close to the device to minimize the impact on switching speed due to stray PCB parasitics.

7.

Package Outline Drawings

The package outline drawings are located at the end of this document and are accessible from the Renesas

website. The package information is the most current data available and is subject to change without revision of

this document.