44.14 SLCD Characteristics

The values in the table below are measured values of power consumption under the following conditions, except where noted:
  • T=25°C. Standby Mode. Low Power waveform Mode. Frame Rate = 32Hz from ULP32K Oscillator.
  • No ACM, ABM or Segment Animation Features activated
  • All Segments on, No Glass Load = 0pF and With Glass Load = 22pF on each COM and SEG line.
  • Contrast Adjustment CTST control set to 0x7 (~2.97V) when using internal VLCD generation
  • No Bias Buffer. No External Bias Output. No Low Resistance Network Enable
  • Reference Refresh Frequency = 500Hz. Power Refresh Frequency = 1kHz
  • ILCD current based on ILCD = Istdby(LCD On) - Istdby (LCD Off). with Istdby = IVDD + IVDDANA
  • To minimize power consumption of the SLCD module use VLCD = VDD or VLCD > VDD + 0.4V
Table 44-50. Liquid Crystal Display Controller Characteristics
Symbol Parameter Conditions Ta Min. Typ. Max. Units
VDD Power Supply for SLCD operation 1.62 3.3 3.63 V
VLCD VLCD maximum value VDD=1.62V, Contrast Adjustment: CTST = 0xF Iload = 10µA

Max 85°C

Typ 25°C

 2.94 3.05 3.15 V
Iload = 20µA 2.78 2.97 3.13
VDD=1.8V, Contrast Adjustment: CTST = 0xF Iload = 10µA 3.32 3.44 3.55
Iload = 20µA. 3.17 3.36 3.53
VDD>2V, Contrast Adjustment: CTST = 0xF Iload = 10µA 3.32 3.48 3.71
Iload = 20µA. 3.28 3.45 3.69
CVLCD External VLCD capacitor - 1 - µF
Fframe LCD Frame Frequency - 32 120 Hz
Tstart VLCD Start-up Time VDD=2.4V, CTST=0x7 - 25 - ms
VLCD LCD Regulated Voltages Contrast Adjustment: CTST = 0x7 - 3 - V
BIAS3/4 - 3*VLCD/4 -
BIAS1/2 - VLCD/2 -
BIAS1/4 - VLCD/4 -
BIAS2/3 - 2*VLCD/3 -
BIAS1/3 - VLCD/3 -
ILCD LCD current supply With no Glass (Load = 0pF) Internal VLCD generation Nb COM = 8 Nb SEG = 40 (1/4 Bias) VDD = 3.6V

Max 85°C

Typ 25°C

 1.68 5.97 µA
VDD = 2.4V 2.41 15.34
Nb COM = 4 Nb SEG = 44 (1/3 Bias) VDD = 3.6V 1.63 6.61
VDD = 2.4V 2.28 16.86
Nb COM = 1 Nb SEG = 44 (Static Bias) VDD = 3.6V 1.20 5.97
VDD = 2.4V 1.25 15.24
External VLCD generation (VLCD = 3.0V) Nb COM = 8 Nb SEG = 40 (1/4 Bias) VDD = 3.6V 1.03 5.76
VDD = 2.4V 1.25 7.30
Nb COM = 4 Nb SEG = 44 (1/3 Bias) VDD = 3.6V 1.06 5.66
VDD = 2.4V 1.26 7.39
Nb COM = 1 Nb SEG = 44 (Static Bias) VDD = 3.6V 1.07 5.81
VDD = 2.4V 1.22 7.04
ILCD LCD current supply With Glass (Load = 22pF) Internal VLCD generation Nb COM = 8 Nb SEG = 40 (1/4 Bias) VDD = 3.6V

Max 85°C

Typ 25°C

 3.02 8.06 µA
VDD = 2.4V 4.84 18.44
Nb COM = 4 Nb SEG = 44 (1/3 Bias) VDD = 3.6V 2.44 8.22
VDD = 2.4V 3.84 17.64
Nb COM = 1 Nb SEG = 44 (Static Bias) VDD = 3.6V 1.78 6.86
VDD = 2.4V 1.99 15.23
External VLCD generation (VLCD = 3.0V) Nb COM = 8 Nb SEG = 40 (1/4 Bias) VDD = 3.6V

Max 85°C

Typ 25°C

 1.09 5.96
VDD = 2.4V 1.25 6.62
Nb COM = 4 Nb SEG = 44 (1/3 Bias) VDD = 3.6V 1.06 6.34
VDD = 2.4V 1.27 8.41
Nb COM = 1 Nb SEG = 44 (Static Bias) VDD = 3.6V 1.23 6.38
VDD = 2.4V 1.22 8.00
Table 44-51. Liquid Crystal Display Contrast Values (VLCD)
Symbol Parameter Conditions CTRLC.CTST value Typ. Units
VLCD Contrast VLCD Values

Iload = 20µA

VDD>2V

VLCD generated internally

 0x0 2.45 V
0x1 2.51
0x2 2.57
0x3 2.64
0x4 2.71
0x5 2.78
0x6 2.84
0x7 2.91
0x8 2.98
0x9 3.04
0xA 3.11
0xB 3.18
0xC 3.25
0xD 3.31
0xE 3.38
0xF 3.45