PCA9620H NXP [NXP Semiconductors], PCA9620H Datasheet - Page 37

• Manufacturer Part Number: PCA9620H
• Description: Universal LCD driver for low multiplex rates
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCA9620
Product data sheet
Table 29.
[1]
[2]
The slope factors imply a linear correction, however the implementation is set in steps of
30 mV (parameter n in
Remark: After reset, V
value of VT[7:0] is generated by the reset value of TD[7:0] (40h, representing 20 °C).
Temperature compensation is implemented by adding an offset VT[7:0] to the VPR[7:0]
value. VT[7:0] is a two’s complement number that equals 0h at 20 °C. The final result for
V
Remark: Care must be taken that the ranges of VPR[7:0] and VT[7:0] don’t cause clipping
and hence undesired results. The device will not permit overflow or underflow and will
clamp results to either end of the range.
SLA[2:0] to SLD[2:0] value
000
001
010
011
100
101
110
111
Fig 29. Example of segmented temperature coefficients
LCD
[2]
The relationship between the temperature coefficients MA to MD and the slope factor is derived from the
following equation:
Default value.
calculation is an 8-bit positive number (see
Temperature coefficients
All information provided in this document is subject to legal disclaimers.
Mx
−40
0h
Rev. 1 — 9 December 2010
LCD
Table 27 on page
=
SLA
0.9375
--------------- -
MA
0.03
is fixed because the VPR[7:0] bit field is reset logic 0. The
Corresponding slope factor
(mV/°C)
0
−4
−8
−16
−40
+4
+8
+16
20h
−10
×
slope
------------- -
1000
SLB
MB
.
31).
40h
20
Universal LCD driver for low multiplex rates
zero offset
at 20 °C
SLC
MC
Equation 6 on page
60h
50
SLD
MD
Temperature coefficients
MA, MB, MC, MD
0.00
−0.125
−0.25
−0.5
−1.25
0.125
0.25
0.5
7Fh
Temperature (°C)
79
013aaa261
31).
PCA9620
TD[7:0]
© NXP B.V. 2010. All rights reserved.
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