PCF8813 datasheet(37/72 Pages) PHILIPS

37 / 72 page

2004 Mar 05

Philips Semiconductors

Product speciﬁcation

(67 + 1)

× 102 pixels matrix LCD driver

PCF8813

The generated voltage at VLCD is dependent on the

temperature, programmed temperature coefficient (TC)

and the programmed voltage at the reference temperature

(TCUT):

TCUT and voltages a and b for each temperature

coefficient are quoted in Table 17. The maximum voltage

that can be generated is dependent on the voltage of VDD2

and the display load current.

As the programming range for the internally generated

VLCD allows values above the maximum allowed VLCD,

the user must ensure that while setting the VPR

under all conditions and including all tolerances the

VLCD maximum limit of 9.0 V will never be exceeded.

For a particular liquid crystal, the optimum VLCD can be

calculated for a given multiplex rate. For 1 : 68, the

optimum operating voltage of the liquid crystal can be

calculated as;

where Vth is the threshold voltage of the liquid crystal used.

LCD

[]

1TC

CUT

–

()

[]

LCD

168

----------

–





---------------------------------------

6.98

Table 17 Parameters of HV generator programming (typical values)

Nominal temperature = 27

°C; temperature coefﬁcients calculated at nominal VLCD = 8.6 V.

SYMBOL

PARAMETER

TC0

TC1

TC2

TC3

UNIT

ﬁrst level VLCD voltage

4.57

4.27

4.01

3.84

programmed voltage step

30.5

28.5

26.7

25.6

TCUT

reference temperature

°C

temperature coefﬁcient

0.00

−0.25

−0.48

−0.64

mV/K

handbook, full pagewidth

MGT847

VLCD

VOP

. . .

. . . FD FE FF

Fig.35 VLCD as a function of VOP[7:0] programming.

If VPR[6:0] is set to zero, the charge pump is turned off.

Depending on VPR restrictions defined in Table 17 and depending on VCAL, not all VOP[7:0] values can be selected.

PCF8813 датащи(PDF) 37 Page - NXP Semiconductors

PCF8813 датащи(HTML) 37 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 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72

датащи скачать

ссылки URL