PCF8535 datasheet(41/52 Pages) PHILIPS

41 / 52 page

1999 Aug 24

Philips Semiconductors

Objective speciﬁcation

× 133 pixel matrix driver

PCF8535

handbook, full pagewidth

MGS687

DISPLAY 65

× 133 PIXELS

VDD1

VDD3

I/O

VSS1,

VSS2

Cext

Rsupply

Rcommon

RI/O

VLCD

PCF8535

133

Fig.23 Application diagram (COG).

The required minimum value for the external capacitors in an application with the PCF8535 are:

Cext for VLCD, VSS1 and VSS2 = 100 nF (min.) (recommended 470 nF to 1 µF); Cext for VDD1 to VDD3, VSS1 and

VSS2 = 470 nF (recommended capacitor larger than the capacitor for VLCD, VSS1 and VSS2).

Higher capacitor values are recommended for ripple reduction.

For COG applications the recommended ITO track resistance is to be minimized for the I/O and supply connections.

Maximum values for supply tracks (Rsupply) are 120 Ω. Maximum values for the common resistance to the source,

(Rcommon) are 120 Ω. Higher track resistance reduces performance and increases current consumption.

Three I/O lines are required for the COG module; SDA, SCL and RES (optional). Other signals may be fixed on the

module to appropriate levels. RI/O should also be minimized. In particular, if the I2C-bus acknowledge or temperature

read back is required, the RI/O for the SDA line must be carefully considered in conjunction with the value of the external

pull-up resistor.

PCF8535 датащи(PDF) 41 Page - NXP Semiconductors