PCF8535 datasheet(14/52 Pages) PHILIPS

14 / 52 page

1999 Aug 24

Philips Semiconductors

Objective speciﬁcation

× 133 pixel matrix driver

PCF8535

handbook, full pagewidth

MGS472

VLCD

. . . 5F

LOW

HIGH

Fig.5 VOP programming of PCF8535.

VOP[6:0] programming (00H to 7FH, programming range LOW and HIGH).

7.14

Voltage multiplier control

7.14.1

S[1:0]

The PCF8535 incorporates a software configurable

voltage multiplier. After reset (RES) the voltage multiplier

is set to 2

× VDD2. Other voltage multiplier factors are set

via the HV-gen command page. Before switching on the

charge pump, the charge pump has to be pre-charged

using the following sequence.

A starting state of HVE = 0, DOF = 0, PD = 1 and DM = 0

is assumed. A small delay between steps is indicated.

The recommended wait period is 20

µs per 100 nF of

capacitance on VLCD1.

1. Set DM = 1 and PD = 0

2. Delay

3. Set the multiplication factor to 2 by setting S[1:0] = 00

4. Set the required VOP and PRS.

5. Set HVE = 1 to switch-on the charge pump with a

multiplication factor of 2

6. Delay

7. Increase the number of stages, one at a time, with a

delay between each until the required level is

achieved.

Table 7

HV generator multiplication factor

S[1]

S[0]

MULTIPLICATION FACTOR

× VDD2

PCF8535 Datasheet(PDF) 14 Page - NXP Semiconductors

PCF8535 Datasheet(HTML) 14 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

Datasheet Download

Link URL