SITRONIX ST7781

ST
ST7781
262K Color Single –Chip TFT Controller/Driver
1. Introduction
The ST7781 is a single-chip controller/driver for 262K-color, graphic type TFT-LCD. It consists of 720 source line and
320 gate line driving circuits. This chip is capable of connecting directly to an external microprocessor, and accepts,
8-bits/9-bits/16-bits/18-bits parallel interface. Display data can be stored in the on-chip display data RAM of 240x320x18
bits. It can perform display data RAM read/write operation with no external operation clock to minimize power
consumption. In addition, because of the integrated power supply circuit necessary to drive liquid crystal; it is possible to
make a display system with the fewest components.
2. Features
Driver Output:
- 720ch Source Outputs (240 X RGB)
- 320ch Gate Outputs
- Common Electrode Output
Single Chip Display RAM:
-Capacity: 240x320x18 bit
Support Display Color
- 65K Color
- 262K Color
- 8-color (Idle Mode)
Supported LC Type Option
- MVA LC Type
- Transflective LC Type
- Transmissive LC Type
Supported MCU Interface
- 8/9/16/18-bit Interface with 8080-Series MCU
- 3-line serial interface
Display Features
- Partial Display Mode
- Resizing Function (x1/2, x1/4)
Build-in Circuit
- DC/DC Converter
- Adjustable VCOM Generation
- Oscillator for Display Clock Generation
- Timing Controller
- Non-volatile Memory for Factory Default Value
- Line Inversion, Frame Inversion
Non-Volatile Memory
- 7-bits for ID Code
- 5-bits for VCOM Adjustment
Supply Voltage Range
- Analog Supply Voltage (VDD) Range: 2.5V to 3.3V
- I/O Supply Voltage (VDDI) Range: 1.65V to 3.3V
Output Voltage Level
- GVDD – AGND: 3V to (AVDD-0.5) V
- AVDD – AGND: 4.5V to 5.6V
- VCL – AGND: -2.0V to -3.0V
- VCOMH – AGND: 3.0V to (AVDD-0.5) V
- VCOML – AGND: (VCL+0.5) V to 0.0V
- VGH – AGND: 10V to 16.5V
- VGL – AGND: -5V to -14V
Lower Power Consumption
- CMOS Compatible Inputs
- Optimized Layout for COG Assembly
- Operate Temperature Range: -30 ℃ ~ +85℃
ST7781
8080 Parallel Interface :8bit/ 9 bit/16 bit /18bit
Serial Interface :3- line
Sitronix Technology Corp. reserves the right to change the contents in this document without prior notice.
ST7781
3. Pad Arrangement
Chip Size: 18163um x 800um
Chip Thickness : 280um or 300um (typ.)
DB4
DB3
DB2
DB1
DB0
DUMMY
SDO
SDI
/RD
/WR /SCL
20
15
20
………
2
230
Ver. 1.7
220
C23N
C23N
C23N
C23N
C23P
C23P
C23P
C23P
C23P
C23P
C23P
DUMMY
DUMMY
S712
S713
S714
S715
S716
S717
S718
S719
S720
DUMMY
DUMMY
G2
G4
G6
G8
G10
G12
G14
G16
G18
210
C22P
C22P
C22P
C22P
C22P
C22P
C22P
C23N
C23N
C23N
X
200
Bump View
VGH
VGH
VGH
DUMMY
DUMMY
C21N
C21N
C21N
C21N
C21P
C21P
C21P
C21P
C22N
C22N
C22N
C22N
C22N
C22N
C22N
190
Alignment Mark: A2 (X , Y) = (8751 , 252.5)
VGL
VGL
VGL
VGL
AGND
AGND
AGND
VGH
VGH
VGH
180
15
C12P
C12P
C12P
C12P
C11N
C11N
C11N
C11N
C11N
C11P
C11P
C11P
C11P
C11P
VGL
VGL
VGL
VGL
VGL
VGL
Y
170
VDD
VDD
TESTO
TESTO
C12N
C12N
C12N
C12N
C12N
C12P
………
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
160
10 15
Face Up
(Bump View)
10
DUMMY
S361
S362
S363
S364
S365
S366
S367
S368
S369
150
AVDD
VCI1
VCI1
VCI1
VDD
VDD
VDD
VDD
VDD
VDD
15
140
20
130
15
120
Alignment Mark: A1 (X , Y) = (-8751 , 252.5)
VCL
VCL
VCL
VCL
VCL
AVDD
AVDD
AVDD
AVDD
AVDD
110
15
VCOM
VCOM
VCOM
VCOM
VCOMH
VCOMH
VCOMH
VCOMH
VCOMH
VCOMH
VCOML
VCOML
VCOML
VCOML
GVDD
GVDD
GVDD
DUMMY
DUMMY
DUMMY
S353
S354
S355
S356
S357
S358
S359
S360
DUMMY
100
20
AGND
AGND
AGND
AGND
V25
DUMMY
DUMMY
VCOM
VCOM
VCOM
90
15
10
VCC
VCC
VCC
DUMMY
DGND
DGND
DGND
DGND
DGND
DGND
DGND
DGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
………
15
10
80
VDDI
VDDI
VCC
VCC
VCC
VCC
VCC
VCC
VCC
VCC
Alignment Marks
70
DUMMY
DUMMY
TESTO
TESTO
DUMMY
DUMMY
VDDI
VDDI
VDDI
VDDI
60
RS
/CS
DUMMY
OSC
FMARK
DUMMY
TESTI
TESTI
TESTI
TESTI
2. 50um x 80um
Input Pads
Pad 1 to 243.
50
1. 16um x 90um
Gate: G1 ~ G320
Source: S1 ~ S720
G 17
G 15
G 13
G 11
G9
G7
G5
G3
G1
DUMMY
DUMMY
S1
S2
S3
S4
S5
S6
S7
S8
S9
40
DB12
DB11
DB10
DB9
DB8
DUMMY
DUMMY
DB7
DB6
DB5
30
Au Bump Size:
20
TESTI
TESTI
TESTI
TESTI
DB17
DB16
DB15
DB14
DB13
DUMMY
Au Bump Height: 15um (typ.)
………
Coordinate Origin: Chip Center
DUMMY
G319
G317
G315
G313
G311
G309
G307
G305
G303
10
Pad Location: Pad Center.
DUMMY
SW_EE
DUMMY
DUMMY
DUMMY
TESTO
IM0
IM1
IM2
IM3
DUMMY
TESTO
TESTO
TESTO
TESTO
TESTO
TESTO
TESTO
RESET
RESET
G304
G306
G308
G310
G312
G314
G316
G318
G320
DUMMY
ST7781
S1~S720
G1~G320
DUMMY
(No.244~1291)
I/O Pads
(No.1~243)
Ver. 1.7
3
ST7781
4. Pad Center Coordinates
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
1
DUMMY
-8610
-304
41
DB4
-5585
-304
2
SW_EE
-8540
-304
42
DB3
-5505
-304
3
DUMMY
-8470
-304
43
DB2
-5425
-304
4
DUMMY
-8400
-304
44
DB1
-5345
-304
5
DUMMY
-8330
-304
45
DB0
-5265
-304
6
TESTO
-8260
-304
46
DUMMY
-5180
-304
7
IM0
-8190
-304
47
SDO
-5110
-304
8
IM1
-8120
-304
48
SDI
-5040
-304
9
IM2
-8050
-304
49
/RD
-4970
-304
10
IM3
-7980
-304
50
/WR /SCL
-4900
-304
11
DUMMY
-7910
-304
51
RS
-4830
-304
12
TESTO
-7840
-304
52
/CS
-4760
-304
13
TESTO
-7770
-304
53
DUMMY
-4690
-304
14
TESTO
-7700
-304
54
OSC
-4620
-304
15
TESTO
-7630
-304
55
FMARK
-4550
-304
16
TESTO
-7560
-304
56
DUMMY
-4480
-304
17
TESTO
-7490
-304
57
TESTI
-4410
-304
18
TESTO
-7420
-304
58
TESTI
-4340
-304
19
RESET
-7350
-304
59
TESTI
-4270
-304
20
RESET
-7280
-304
60
TESTI
-4200
-304
21
TESTI
-7210
-304
61
DUMMY
-4130
-304
22
TESTI
-7140
-304
62
DUMMY
-4060
-304
23
TESTI
-7070
-304
63
TESTO
-3990
-304
24
TESTI
-7000
-304
64
TESTO
-3920
-304
25
DB17
-6905
-304
65
DUMMY
-3850
-304
26
DB16
-6825
-304
66
DUMMY
-3780
-304
27
DB15
-6745
-304
67
VDDI
-3710
-304
28
DB14
-6665
-304
68
VDDI
-3640
-304
29
DB13
-6585
-304
69
VDDI
-3570
-304
30
DUMMY
-6495
-304
70
VDDI
-3500
-304
31
DB12
-6405
-304
71
VDDI
-3430
-304
32
DB11
-6325
-304
72
VDDI
-3360
-304
33
DB10
-6245
-304
73
VCC
-3290
-304
34
DB9
-6165
-304
74
VCC
-3220
-304
35
DB8
-6085
-304
75
VCC
-3150
-304
36
DUMMY
-5990
-304
76
VCC
-3080
-304
37
DUMMY
-5920
-304
77
VCC
-3010
-304
38
DB7
-5825
-304
78
VCC
-2940
-304
39
DB6
-5745
-304
79
VCC
-2870
-304
40
DB5
-5665
-304
80
VCC
-2800
-304
Ver. 1.7
4
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
81
VCC
-2730
-304
121
VCOML
70
-304
82
VCC
-2660
-304
122
VCOML
140
-304
83
VCC
-2590
-304
123
VCOML
210
-304
84
DUMMY
-2520
-304
124
VCOML
280
-304
85
DGND
-2450
-304
125
GVDD
350
-304
86
DGND
-2380
-304
126
GVDD
420
-304
87
DGND
-2310
-304
127
GVDD
490
-304
88
DGND
-2240
-304
128
DUMMY
560
-304
89
DGND
-2170
-304
129
DUMMY
630
-304
90
DGND
-2100
-304
130
DUMMY
700
-304
91
DGND
-2030
-304
131
VCL
770
-304
92
DGND
-1960
-304
132
VCL
840
-304
93
AGND
-1890
-304
133
VCL
910
-304
94
AGND
-1820
-304
134
VCL
980
-304
95
AGND
-1750
-304
135
VCL
1050
-304
96
AGND
-1680
-304
136
AVDD
1120
-304
97
AGND
-1610
-304
137
AVDD
1190
-304
98
AGND
-1540
-304
138
AVDD
1260
-304
99
AGND
-1470
-304
139
AVDD
1330
-304
100
AGND
-1400
-304
140
AVDD
1400
-304
101
AGND
-1330
-304
141
AVDD
1470
-304
102
AGND
-1260
-304
142
VCI1
1540
-304
103
AGND
-1190
-304
143
VCI1
1610
-304
104
AGND
-1120
-304
144
VCI1
1680
-304
105
V25
-1050
-304
145
VDD
1750
-304
106
DUMMY
-980
-304
146
VDD
1820
-304
107
DUMMY
-910
-304
147
VDD
1890
-304
108
VCOM
-840
-304
148
VDD
1960
-304
109
VCOM
-770
-304
149
VDD
2030
-304
110
VCOM
-700
-304
150
VDD
2100
-304
111
VCOM
-630
-304
151
VDD
2170
-304
112
VCOM
-560
-304
152
VDD
2240
-304
113
VCOM
-490
-304
153
VDD
2310
-304
114
VCOM
-420
-304
154
VDD
2380
-304
115
VCOMH
-350
-304
155
VDD
2450
-304
116
VCOMH
-280
-304
156
VDD
2520
-304
117
VCOMH
-210
-304
157
VDD
2590
-304
118
VCOMH
-140
-304
158
VDD
2660
-304
119
VCOMH
-70
-304
159
VDD
2730
-304
120
VCOMH
0
-304
160
VDD
2800
-304
Ver. 1.7
5
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
161
VDD
2870
-304
201
VGH
5670
-304
162
VDD
2940
-304
202
VGH
5740
-304
163
TESTO
3010
-304
203
VGH
5810
-304
164
TESTO
3080
-304
204
DUMMY
5880
-304
165
C12N
3150
-304
205
DUMMY
5950
-304
166
C12N
3220
-304
206
C21N
6020
-304
167
C12N
3290
-304
207
C21N
6090
-304
168
C12N
3360
-304
208
C21N
6160
-304
169
C12N
3430
-304
209
C21N
6230
-304
170
C12P
3500
-304
210
C21P
6300
-304
171
C12P
3570
-304
211
C21P
6370
-304
172
C12P
3640
-304
212
C21P
6440
-304
173
C12P
3710
-304
213
C21P
6510
-304
174
C12P
3780
-304
214
C22N
6580
-304
175
C11N
3850
-304
215
C22N
6650
-304
176
C11N
3920
-304
216
C22N
6720
-304
177
C11N
3990
-304
217
C22N
6790
-304
178
C11N
4060
-304
218
C22N
6860
-304
179
C11N
4130
-304
219
C22N
6930
-304
180
C11P
4200
-304
220
C22N
7000
-304
181
C11P
4270
-304
221
C22P
7070
-304
182
C11P
4340
-304
222
C22P
7140
-304
183
C11P
4410
-304
223
C22P
7210
-304
184
C11P
4480
-304
224
C22P
7280
-304
185
VGL
4550
-304
225
C22P
7350
-304
186
VGL
4620
-304
226
C22P
7420
-304
187
VGL
4690
-304
227
C22P
7490
-304
188
VGL
4760
-304
228
C23N
7560
-304
189
VGL
4830
-304
229
C23N
7630
-304
190
VGL
4900
-304
230
C23N
7700
-304
191
VGL
4970
-304
231
C23N
7770
-304
192
VGL
5040
-304
232
C23N
7840
-304
193
VGL
5110
-304
233
C23N
7910
-304
194
VGL
5180
-304
234
C23N
7980
-304
195
AGND
5250
-304
235
C23P
8050
-304
196
AGND
5320
-304
236
C23P
8120
-304
197
AGND
5390
-304
237
C23P
8190
-304
198
VGH
5460
-304
238
C23P
8260
-304
199
VGH
5530
-304
239
C23P
8330
-304
200
VGH
5600
-304
240
C23P
8400
-304
Ver. 1.7
6
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
241
C23P
8470
-304
281
G248
8067
299
242
DUMMY
8540
-304
282
G246
8051
182
243
DUMMY
8610
-304
283
G244
8035
299
244
DUMMY
8659
182
284
G244
8019
182
245
G320
8643
299
285
G240
8003
299
246
G318
8627
182
286
G240
7987
182
247
G316
8611
299
287
G236
7971
299
248
G314
8595
182
288
G234
7955
182
249
G312
8579
299
289
G232
7939
299
250
G310
8563
182
290
G230
7923
182
251
G308
8547
299
291
G228
7907
299
252
G306
8531
182
292
G226
7891
182
253
G304
8515
299
293
G224
7875
299
254
G302
8499
182
294
G222
7859
182
255
G300
8483
299
295
G220
7843
299
256
G298
8467
182
296
G218
7827
182
257
G296
8451
299
297
G216
7811
299
258
G294
8435
182
298
G214
7795
182
259
G292
8419
299
299
G212
7779
299
260
G290
8403
182
300
G210
7763
182
261
G288
8387
299
301
G208
7747
299
262
G286
8371
182
302
G206
7731
182
263
G284
8355
299
303
G204
7715
299
264
G282
8339
182
304
G202
7699
182
265
G280
8323
299
305
G200
7683
299
266
G278
8307
182
306
G198
7667
182
267
G276
8291
299
307
G196
7651
299
268
G274
8275
182
308
G194
7635
182
269
G272
8259
299
309
G192
7619
299
270
G270
8243
182
310
G190
7603
182
271
G268
8227
299
311
G188
7587
299
272
G266
8211
182
312
G186
7571
182
273
G264
8195
299
313
G184
7555
299
274
G262
8179
182
314
G182
7539
182
275
G260
8163
299
315
G180
7523
299
276
G258
8147
182
316
G178
7507
182
277
G256
8131
299
317
G176
7491
299
278
G254
8115
182
318
G174
7475
182
279
G252
8099
299
319
G172
7459
299
280
G250
8083
182
320
G170
7443
182
Ver. 1.7
7
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
321
G168
7427
299
361
G88
6787
299
322
G166
7411
182
362
G86
6771
182
323
G164
7395
299
363
G84
6755
299
324
G162
7379
182
364
G82
6739
182
325
G160
7363
299
365
G80
6723
299
326
G158
7347
182
366
G78
6707
182
327
G156
7331
299
367
G76
6691
299
328
G154
7315
182
368
G74
6675
182
329
G152
7299
299
369
G72
6659
299
330
G150
7283
182
370
G70
6643
182
331
G148
7267
299
371
G68
6627
299
332
G146
7251
182
372
G66
6611
182
333
G144
7235
299
373
G64
6595
299
334
G142
7219
182
374
G62
6579
182
335
G140
7203
299
375
G60
6563
299
336
G138
7187
182
376
G58
6547
182
337
G136
7171
299
377
G56
6531
299
338
G134
7155
182
378
G54
6515
182
339
G132
7139
299
379
G52
6499
299
340
G130
7123
182
380
G50
6483
182
341
G128
7107
299
381
G48
6467
299
342
G126
7091
182
382
G46
6451
182
343
G124
7075
299
383
G44
6435
299
344
G122
7059
182
384
G42
6419
182
345
G120
7043
299
385
G40
6403
299
346
G118
7027
182
386
G38
6387
182
347
G116
7011
299
387
G36
6371
299
348
G114
6995
182
388
G34
6355
182
349
G112
6979
299
389
G32
6339
299
350
G110
6963
182
390
G30
6323
182
351
G108
6947
299
391
G28
6307
299
352
G106
6931
182
392
G26
6291
182
353
G104
6915
299
393
G24
6275
299
354
G102
6899
182
394
G22
6259
182
355
G100
6883
299
395
G20
6243
299
356
G98
6867
182
396
G18
6227
182
357
G96
6851
299
397
G16
6211
299
358
G94
6835
182
398
G14
6195
182
359
G92
6819
299
399
G12
6179
299
360
G90
6803
182
400
G10
6163
182
Ver. 1.7
8
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
401
G8
6147
299
441
S686
5487
182
402
G6
6131
182
442
S685
5471
299
403
G4
6115
299
443
S684
5455
182
404
G2
6099
182
444
S683
5439
299
405
DUMMY
6083
299
445
S682
5423
182
406
DUMMY
6047
299
446
S681
5407
299
407
S720
6031
182
447
S680
5391
182
408
S719
6015
299
448
S679
5375
299
409
S718
5999
182
449
S678
5359
182
410
S717
5983
299
450
S677
5343
299
411
S716
5967
182
451
S676
5327
182
412
S715
5951
299
452
S675
5311
299
413
S714
5935
182
453
S674
5295
182
414
S713
5919
299
454
S673
5279
299
415
S712
5903
182
455
S672
5263
182
416
S711
5887
299
456
S671
5247
299
417
S710
5871
182
457
S670
5231
182
418
S709
5855
299
458
S669
5215
299
419
S708
5839
182
459
S668
5199
182
420
S707
5823
299
460
S667
5183
299
421
S706
5807
182
461
S666
5167
182
422
S705
5791
299
462
S665
5151
299
423
S704
5775
182
463
S664
5135
182
424
S703
5759
299
464
S663
5119
299
425
S702
5743
182
465
S662
5103
182
426
S701
5727
299
466
S661
5087
299
427
S700
5711
182
467
S660
5071
182
428
S699
5695
299
468
S659
5055
299
429
S698
5679
182
469
S658
5039
182
430
S697
5663
299
470
S657
5023
299
431
S696
5647
182
471
S656
5007
182
432
S695
5631
299
472
S655
4991
299
433
S694
5615
182
473
S654
4975
182
434
S693
5599
299
474
S653
4959
299
435
S692
5583
182
475
S652
4943
182
436
S691
5567
299
476
S651
4927
299
437
S690
5551
182
477
S650
4911
182
438
S689
5535
299
478
S649
4895
299
439
S688
5519
182
479
S648
4879
182
440
S687
5503
299
480
S647
4863
299
Ver. 1.7
9
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
481
S646
4847
182
521
S606
4207
182
482
S645
4831
299
522
S605
4191
299
483
S644
4815
182
523
S604
4175
182
484
S643
4799
299
524
S603
4159
299
485
S642
4783
182
525
S602
4143
182
486
S641
4767
299
526
S601
4127
299
487
S640
4751
182
527
S600
4111
182
488
S639
4735
299
528
S599
4095
299
489
S638
4719
182
529
S598
4079
182
490
S637
4703
299
530
S597
4063
299
491
S636
4687
182
531
S596
4047
182
492
S635
4671
299
532
S595
4031
299
493
S634
4655
182
533
S594
4015
182
494
S633
4639
299
534
S593
3999
299
495
S632
4623
182
535
S592
3983
182
496
S631
4607
299
536
S591
3967
299
497
S630
4591
182
537
S590
3951
182
498
S629
4575
299
538
S589
3935
299
499
S628
4559
182
539
S588
3919
182
500
S627
4543
299
540
S587
3903
299
501
S626
4527
182
541
S586
3887
182
502
S625
4511
299
542
S585
3871
299
503
S624
4495
182
543
S584
3855
182
504
S623
4479
299
544
S583
3839
299
505
S622
4463
182
545
S582
3823
182
506
S621
4447
299
546
S581
3807
299
507
S620
4431
182
547
S580
3791
182
508
S619
4415
299
548
S579
3775
299
509
S618
4399
182
549
S578
3759
182
510
S617
4383
299
550
S577
3743
299
511
S616
4367
182
551
S576
3727
182
512
S615
4351
299
552
S575
3711
299
513
S614
4335
182
553
S574
3695
182
514
S613
4319
299
554
S573
3679
299
515
S612
4303
182
555
S572
3663
182
516
S611
4287
299
556
S571
3647
299
517
S610
4271
182
557
S570
3631
182
518
S609
4255
299
558
S569
3615
299
519
S608
4239
182
559
S568
3599
182
520
S607
4223
299
560
S567
3583
299
Ver. 1.7
10
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
561
S566
3567
182
601
S526
2927
182
562
S565
3551
299
602
S525
2911
299
563
S564
3535
182
603
S524
2895
182
564
S563
3519
299
604
S523
2879
299
565
S562
3503
182
605
S522
2863
182
566
S561
3487
299
606
S521
2847
299
567
S560
3471
182
607
S520
2831
182
568
S559
3455
299
608
S519
2815
299
569
S558
3439
182
609
S518
2799
182
570
S557
3423
299
610
S517
2783
299
571
S556
3407
182
611
S516
2767
182
572
S555
3391
299
612
S515
2751
299
573
S554
3375
182
613
S514
2735
182
574
S553
3359
299
614
S513
2719
299
575
S552
3343
182
615
S512
2703
182
576
S551
3327
299
616
S511
2687
299
577
S550
3311
182
617
S510
2671
182
578
S549
3295
299
618
S509
2655
299
579
S548
3279
182
619
S508
2639
182
580
S547
3263
299
620
S507
2623
299
581
S546
3247
182
621
S506
2607
182
582
S545
3231
299
622
S505
2591
299
583
S544
3215
182
623
S504
2575
182
584
S543
3199
299
624
S503
2559
299
585
S542
3183
182
625
S502
2543
182
586
S541
3167
299
626
S501
2527
299
587
S540
3151
182
627
S500
2511
182
588
S539
3135
299
628
S499
2495
299
589
S538
3119
182
629
S498
2479
182
590
S537
3103
299
630
S497
2463
299
591
S536
3087
182
631
S496
2447
182
592
S535
3071
299
632
S495
2431
299
593
S534
3055
182
633
S494
2415
182
594
S533
3039
299
634
S493
2399
299
595
S532
3023
182
635
S492
2383
182
596
S531
3007
299
636
S491
2367
299
597
S530
2991
182
637
S490
2351
182
598
S529
2975
299
638
S489
2335
299
599
S528
2959
182
639
S488
2319
182
600
S527
2943
299
640
S487
2303
299
Ver. 1.7
11
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
641
S486
2287
182
681
S446
1647
182
642
S485
2271
299
682
S445
1631
299
643
S484
2255
182
683
S444
1615
182
644
S483
2239
299
684
S443
1599
299
645
S482
2223
182
685
S442
1583
182
646
S481
2207
299
686
S441
1567
299
647
S480
2191
182
687
S440
1551
182
648
S479
2175
299
688
S439
1535
299
649
S478
2159
182
689
S438
1519
182
650
S477
2143
299
690
S437
1503
299
651
S476
2127
182
691
S436
1487
182
652
S475
2111
299
692
S435
1471
299
653
S474
2095
182
693
S434
1455
182
654
S473
2079
299
694
S433
1439
299
655
S472
2063
182
695
S432
1423
182
656
S471
2047
299
696
S431
1407
299
657
S470
2031
182
697
S430
1391
182
658
S469
2015
299
698
S429
1375
299
659
S468
1999
182
699
S428
1359
182
660
S467
1983
299
700
S427
1343
299
661
S466
1967
182
701
S426
1327
182
662
S465
1951
299
702
S425
1311
299
663
S464
1935
182
703
S424
1295
182
664
S463
1919
299
704
S423
1279
299
665
S462
1903
182
705
S422
1263
182
666
S461
1887
299
706
S421
1247
299
667
S460
1871
182
707
S420
1231
182
668
S459
1855
299
708
S419
1215
299
669
S458
1839
182
709
S418
1199
182
670
S457
1823
299
710
S417
1183
299
671
S456
1807
182
711
S416
1167
182
672
S455
1791
299
712
S415
1151
299
673
S454
1775
182
713
S414
1135
182
674
S453
1759
299
714
S413
1119
299
675
S452
1743
182
715
S412
1103
182
676
S451
1727
299
716
S411
1087
299
677
S450
1711
182
717
S410
1071
182
678
S449
1695
299
718
S409
1055
299
679
S448
1679
182
719
S408
1039
182
680
S447
1663
299
720
S407
1023
299
Ver. 1.7
12
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
721
S406
1007
182
761
S366
367
182
722
S405
991
299
762
S365
351
299
723
S404
975
182
763
S364
335
182
724
S403
959
299
764
S363
319
299
725
S402
943
182
765
S362
303
182
726
S401
927
299
766
S361
287
299
727
S400
911
182
767
DUMMY
271
182
728
S399
895
299
768
DUMMY
-271
182
729
S398
879
182
769
S360
-287
299
730
S397
863
299
770
S359
-303
182
731
S396
847
182
771
S358
-319
299
732
S395
831
299
772
S357
-335
182
733
S394
815
182
773
S356
-351
299
734
S393
799
299
774
S355
-367
182
735
S392
783
182
775
S354
-383
299
736
S391
767
299
776
S353
-399
182
737
S390
751
182
777
S352
-415
299
738
S389
735
299
778
S351
-431
182
739
S388
719
182
779
S350
-447
299
740
S387
703
299
780
S349
-463
182
741
S386
687
182
781
S348
-479
299
742
S385
671
299
782
S347
-495
182
743
S384
655
182
783
S346
-511
299
744
S383
639
299
784
S345
-527
182
745
S382
623
182
785
S344
-543
299
746
S381
607
299
786
S343
-559
182
747
S380
591
182
787
S342
-575
299
748
S379
575
299
788
S341
-591
182
749
S378
559
182
789
S340
-607
299
750
S377
543
299
790
S339
-623
182
751
S376
527
182
791
S338
-639
299
752
S375
511
299
792
S337
-655
182
753
S374
495
182
793
S336
-671
299
754
S373
479
299
794
S335
-687
182
755
S372
463
182
795
S334
-703
299
756
S371
447
299
796
S333
-719
182
757
S370
431
182
797
S332
-735
299
758
S369
415
299
798
S331
-751
182
759
S368
399
182
799
S330
-767
299
760
S367
383
299
800
S329
-783
182
Ver. 1.7
13
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
801
S328
-799
299
841
S288
-1439
299
802
S327
-815
182
842
S287
-1455
182
803
S326
-831
299
843
S286
-1471
299
804
S325
-847
182
844
S285
-1487
182
805
S324
-863
299
845
S284
-1503
299
806
S323
-879
182
846
S283
-1519
182
807
S322
-895
299
847
S282
-1535
299
808
S321
-911
182
848
S281
-1551
182
809
S320
-927
299
849
S280
-1567
299
810
S319
-943
182
850
S279
-1583
182
811
S318
-959
299
851
S278
-1599
299
812
S317
-975
182
852
S277
-1615
182
813
S316
-991
299
853
S276
-1631
299
814
S315
-1007
182
854
S275
-1647
182
815
S314
-1023
299
855
S274
-1663
299
816
S313
-1039
182
856
S273
-1679
182
817
S312
-1055
299
857
S272
-1695
299
818
S311
-1071
182
858
S271
-1711
182
819
S310
-1087
299
859
S270
-1727
299
820
S309
-1103
182
860
S269
-1743
182
821
S308
-1119
299
861
S268
-1759
299
822
S307
-1135
182
862
S267
-1775
182
823
S306
-1151
299
863
S266
-1791
299
824
S305
-1167
182
864
S265
-1807
182
825
S304
-1183
299
865
S264
-1823
299
826
S303
-1199
182
866
S263
-1839
182
827
S302
-1215
299
867
S262
-1855
299
828
S301
-1231
182
868
S261
-1871
182
829
S300
-1247
299
869
S260
-1887
299
830
S299
-1263
182
870
S269
-1903
182
831
S298
-1279
299
871
S268
-1919
299
832
S297
-1295
182
872
S267
-1935
182
833
S296
-1311
299
873
S266
-1951
299
834
S295
-1327
182
874
S265
-1967
182
835
S294
-1343
299
875
S264
-1983
299
836
S293
-1359
182
876
S263
-1999
182
837
S292
-1375
299
877
S262
-2015
299
838
S291
-1391
182
878
S261
-2031
182
839
S290
-1407
299
879
S260
-2047
299
840
S289
-1423
182
880
S249
-2063
182
Ver. 1.7
14
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
881
S248
-2079
299
921
S208
-2719
299
882
S247
-2095
182
922
S207
-2735
182
883
S246
-2111
299
923
S206
-2751
299
884
S245
-2127
182
924
S205
-2767
182
885
S244
-2143
299
925
S204
-2783
299
886
S243
-2159
182
926
S203
-2799
182
887
S242
-2175
299
927
S202
-2815
299
888
S241
-2191
182
928
S201
-2831
182
889
S240
-2207
299
929
S200
-2847
299
890
S239
-2223
182
930
S199
-2863
182
891
S238
-2239
299
931
S198
-2879
299
892
S237
-2255
182
932
S197
-2895
182
893
S236
-2271
299
933
S196
-2911
299
894
S235
-2287
182
934
S195
-2927
182
895
S234
-2303
299
935
S194
-2943
299
896
S233
-2319
182
936
S193
-2959
182
897
S232
-2335
299
937
S192
-2975
299
898
S231
-2351
182
938
S191
-2991
182
899
S230
-2367
299
939
S190
-3007
299
900
S229
-2383
182
940
S189
-3023
182
901
S228
-2399
299
941
S188
-3039
299
902
S227
-2415
182
942
S187
-3055
182
903
S226
-2431
299
943
S186
-3071
299
904
S225
-2447
182
944
S185
-3087
182
905
S224
-2463
299
945
S184
-3103
299
906
S223
-2479
182
946
S183
-3119
182
907
S222
-2495
299
947
S182
-3135
299
908
S221
-2511
182
948
S181
-3151
182
909
S220
-2527
299
949
S180
-3167
299
910
S219
-2543
182
950
S179
-3183
182
911
S218
-2559
299
951
S178
-3199
299
912
S217
-2575
182
952
S177
-3215
182
913
S216
-2591
299
953
S176
-3231
299
914
S215
-2607
182
954
S175
-3247
182
915
S214
-2623
299
955
S174
-3263
299
916
S213
-2639
182
956
S173
-3279
182
917
S212
-2655
299
957
S172
-3295
299
918
S211
-2671
182
958
S171
-3311
182
919
S210
-2687
299
959
S170
-3327
299
920
S209
-2703
182
960
S169
-3343
182
Ver. 1.7
15
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
961
S168
-3359
299
1001
S128
-3999
299
962
S167
-3375
182
1002
S127
-4015
182
963
S166
-3391
299
1003
S126
-4031
299
964
S165
-3407
182
1004
S125
-4047
182
965
S164
-3423
299
1005
S124
-4063
299
966
S163
-3439
182
1006
S123
-4079
182
967
S162
-3455
299
1007
S122
-4095
299
968
S161
-3471
182
1008
S121
-4111
182
969
S160
-3487
299
1009
S120
-4127
299
970
S159
-3503
182
1010
S119
-4143
182
971
S158
-3519
299
1011
S118
-4159
299
972
S157
-3535
182
1012
S117
-4175
182
973
S156
-3551
299
1013
S116
-4191
299
974
S155
-3567
182
1014
S115
-4207
182
975
S154
-3583
299
1015
S114
-4223
299
976
S153
-3599
182
1016
S113
-4239
182
977
S152
-3615
299
1017
S112
-4255
299
978
S151
-3631
182
1018
S111
-4271
182
979
S150
-3647
299
1019
S110
-4287
299
980
S149
-3663
182
1020
S109
-4303
182
981
S148
-3679
299
1021
S108
-4319
299
982
S147
-3695
182
1022
S107
-4335
182
983
S146
-3711
299
1023
S106
-4351
299
984
S145
-3727
182
1024
S105
-4367
182
985
S144
-3743
299
1025
S104
-4383
299
986
S143
-3759
182
1026
S103
-4399
182
987
S142
-3775
299
1027
S102
-4415
299
988
S141
-3791
182
1028
S101
-4431
182
989
S140
-3807
299
1029
S100
-4447
299
990
S139
-3823
182
1030
S99
-4463
182
991
S138
-3839
299
1031
S98
-4479
299
992
S137
-3855
182
1032
S97
-4495
182
993
S136
-3871
299
1033
S96
-4511
299
994
S135
-3887
182
1034
S95
-4527
182
995
S134
-3903
299
1035
S94
-4543
299
996
S133
-3919
182
1036
S93
-4559
182
997
S132
-3935
299
1037
S92
-4575
299
998
S131
-3951
182
1038
S91
-4591
182
999
S130
-3967
299
1039
S90
-4607
299
1000
S129
-3983
182
1040
S89
-4623
182
Ver. 1.7
16
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
1041
S88
-4639
299
1081
S48
-5279
299
1042
S87
-4655
182
1082
S47
-5295
182
1043
S86
-4671
299
1083
S46
-5311
299
1044
S85
-4687
182
1084
S45
-5327
182
1045
S84
-4703
299
1085
S44
-5343
299
1046
S83
-4719
182
1086
S43
-5359
182
1047
S82
-4735
299
1087
S42
-5375
299
1048
S81
-4751
182
1088
S41
-5391
182
1049
S80
-4767
299
1089
S40
-5407
299
1050
S79
-4783
182
1090
S39
-5423
182
1051
S78
-4799
299
1091
S38
-5439
299
1052
S77
-4815
182
1092
S37
-5455
182
1053
S76
-4831
299
1093
S36
-5471
299
1054
S75
-4847
182
1094
S35
-5487
182
1055
S74
-4863
299
1095
S34
-5503
299
1056
S73
-4879
182
1096
S33
-5519
182
1057
S72
-4895
299
1097
S32
-5535
299
1058
S71
-4911
182
1098
S31
-5551
182
1059
S70
-4927
299
1099
S30
-5567
299
1060
S69
-4943
182
1100
S29
-5583
182
1061
S68
-4959
299
1101
S28
-5599
299
1062
S67
-4975
182
1102
S27
-5615
182
1063
S66
-4991
299
1103
S26
-5631
299
1064
S65
-5007
182
1104
S25
-5647
182
1065
S64
-5023
299
1105
S24
-5663
299
1066
S63
-5039
182
1106
S23
-5679
182
1067
S62
-5055
299
1107
S22
-5695
299
1068
S61
-5071
182
1108
S21
-5711
182
1069
S60
-5087
299
1109
S20
-5727
299
1070
S59
-5103
182
1110
S19
-5743
182
1071
S58
-5119
299
1111
S18
-5759
299
1072
S57
-5135
182
1112
S17
-5775
182
1073
S56
-5151
299
1113
S16
-5791
299
1074
S55
-5167
182
1114
S15
-5807
182
1075
S54
-5183
299
1115
S14
-5823
299
1076
S53
-5199
182
1116
S13
-5839
182
1077
S52
-5215
299
1117
S12
-5855
299
1078
S51
-5231
182
1118
S11
-5871
182
1079
S50
-5247
299
1119
S10
-5887
299
1080
S49
-5263
182
1120
S9
-5903
182
Ver. 1.7
17
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
1121
S8
-5919
299
1161
G61
-6579
182
1122
S7
-5935
182
1162
G63
-6595
299
1123
S6
-5951
299
1163
G65
-6611
182
1124
S5
-5967
182
1164
G67
-6627
299
1125
S4
-5983
299
1165
G69
-6643
182
1126
S3
-5999
182
1166
G71
-6659
299
1127
S2
-6015
299
1167
G73
-6675
182
1128
S1
-6031
182
1168
G75
-6691
299
1129
DUMMY
-6047
299
1169
G77
-6707
182
1130
DUMMY
-6081.62
299
1170
G79
-6723
299
1131
G1
-6099
182
1171
G81
-6739
182
1132
G3
-6115
299
1172
G83
-6755
299
1133
G5
-6131
182
1173
G85
-6771
182
1134
G7
-6147
299
1174
G87
-6787
299
1135
G9
-6163
182
1175
G89
-6803
182
1136
G11
-6179
299
1176
G91
-6819
299
1137
G13
-6195
182
1177
G93
-6835
182
1138
G15
-6211
299
1178
G95
-6851
299
1139
G17
-6227
182
1179
G97
-6867
182
1140
G19
-6243
299
1180
G99
-6883
299
1141
G21
-6259
182
1181
G101
-6899
182
1142
G23
-6275
299
1182
G103
-6915
299
1143
G25
-6291
182
1183
G105
-6931
182
1144
G27
-6307
299
1184
G107
-6947
299
1145
G29
-6323
182
1185
G109
-6963
182
1146
G31
-6339
299
1186
G111
-6979
299
1147
G33
-6355
182
1187
G113
-6995
182
1148
G35
-6371
299
1188
G115
-7011
299
1149
G37
-6387
182
1189
G117
-7027
182
1150
G39
-6403
299
1190
G119
-7043
299
1151
G41
-6419
182
1191
G121
-7059
182
1152
G43
-6435
299
1192
G123
-7075
299
1153
G45
-6451
182
1193
G125
-7091
182
1154
G47
-6467
299
1194
G127
-7107
299
1155
G49
-6483
182
1195
G129
-7123
182
1156
G51
-6499
299
1196
G131
-7139
299
1157
G53
-6515
182
1197
G133
-7155
182
1158
G55
-6531
299
1198
G135
-7171
299
1159
G57
-6547
182
1199
G137
-7187
182
1160
G59
-6563
299
1200
G139
-7203
299
Ver. 1.7
18
ST7781
PAD No.
PIN Name
X
Y
PAD No.
PIN Name
X
Y
1201
G141
-7219
182
1241
G221
-7859
182
1202
G143
-7235
299
1242
G223
-7875
299
1203
G145
-7251
182
1243
G225
-7891
182
1204
G147
-7267
299
1244
G227
-7907
299
1205
G149
-7283
182
1245
G229
-7923
182
1206
G151
-7299
299
1246
G231
-7939
299
1207
G153
-7315
182
1247
G233
-7955
182
1208
G155
-7331
299
1248
G235
-7971
299
1209
G157
-7347
182
1249
G237
-7987
182
1210
G159
-7363
299
1250
G239
-8003
299
1211
G161
-7379
182
1251
G241
-8019
182
1212
G163
-7395
299
1252
G243
-8035
299
1213
G165
-7411
182
1253
G245
-8051
182
1214
G167
-7427
299
1254
G247
-8067
299
1215
G169
-7443
182
1255
G249
-8083
182
1216
G171
-7459
299
1256
G251
-8099
299
1217
G173
-7475
182
1257
G253
-8115
182
1218
G175
-7491
299
1258
G255
-8131
299
1219
G177
-7507
182
1259
G257
-8147
182
1220
G179
-7523
299
1260
G259
-8163
299
1221
G181
-7539
182
1261
G261
-8179
182
1222
G183
-7555
299
1262
G263
-8195
299
1223
G185
-7571
182
1263
G265
-8211
182
1224
G187
-7587
299
1264
G267
-8227
299
1225
G189
-7603
182
1265
G269
-8243
182
1226
G191
-7619
299
1266
G271
-8259
299
1227
G193
-7635
182
1267
G273
-8275
182
1228
G195
-7651
299
1268
G275
-8291
299
1229
G197
-7667
182
1269
G277
-8307
182
1230
G199
-7683
299
1270
G279
-8323
299
1231
G201
-7699
182
1271
G281
-8339
182
1232
G203
-7715
299
1272
G283
-8355
299
1233
G205
-7731
182
1273
G285
-8371
182
1234
G207
-7747
299
1274
G287
-8387
299
1235
G209
-7763
182
1275
G289
-8403
182
1236
G211
-7779
299
1276
G291
-8419
299
1237
G213
-7795
182
1277
G293
-8435
182
1238
G215
-7811
299
1278
G295
-8451
299
1239
G217
-7827
182
1279
G297
-8467
182
1240
G219
-7843
299
1280
G299
-8483
299
Ver. 1.7
19
ST7781
PAD No.
PIN Name
X
Y
1281
G301
-8499
182
1282
G303
-8515
299
1283
G305
-8531
182
1284
G307
-8547
299
1285
G309
-8563
182
1286
G311
-8579
299
1287
G313
-8595
182
1288
G315
-8611
299
1289
G317
-8627
182
1290
G319
-8643
299
1291
DUMMY
-8659
182
Ver. 1.7
20
ST7781
5. Block Diagram
Ver. 1.7
21
ST7781
6. Pin Description
6.1 Power Supply Pin
Name
VDD
VDDI
AGND
DGND
I/O
I
I
I
I
Description
Power supply for analog, digital system and booster circuit
Power supply for I/O system
System ground for analog system and booster circuit.
System ground for I/O system and internal digital system.
Connect Pin
VDD
VDDI
GND
GND
6.2 Interface Logic Pin
Name
I/O
Description
-Select the MCU system interface mode
IM3
IM2
IM1
IM0
MCU-Interface Mode
0
0
1
0
I80-system 16-bit interface
Connect Pin
DB Pin Use
DB[17:10]
DB[8:1]
DB[17:10]
SDI,SDO
DB[17:0]
DB[17:9]
0
0
1
1
I80-system 8-bit interface
0
1
0
ID
Serial Peripheral interface (SPI)
1
0
1
0
I80-system 18-bit interface
1
0
1
1
I80-system 9-bit interface
-If not used, please connect this pin to VDDI or DGND
-When the serial peripheral interface is selected, IM0_ID pin is used for the device
ID code setting.
RESET
I
-This signal will reset the driver and it must be applied to properly initialize the chip.
-Chip select input pin and signal is active low.
/CS
I
-This pin can be permanently fixed “Low” in MCU interface mode only.
-Display data or command selection pin in MCU interface.
RS
I
RS =’1’: Display Data or Parameter.
RS =’0’: Command.
/RD
I
-Read enable in 8080 MCU parallel interface.
-Write operation enable pin in 8080 MCU parallel interface.
/WR/SCL
I
-In SPI interface, this pin is used as SCL.
-If not used, please connect this pin to VDDI or DGND.
-SPI interface data input pin.
SDI
I
-The data is latched on the rising edge of the SCL signal.
-If not used, please connect this pin to VDDI or DGND.
-SPI interface data output pin.
SDO
O
-The data is outputted on the falling edge of the SCL signal.
-Let SDO as floating when not in use.
-To use extended command set, please connect this pin to VDDI.
SW_EE
I
-During normal operation, please let this pin open.
-Output a frame head pulse signal is used as synchronies MCU to frame rate
FMARK
O
-If not used, Let this pin open
Note1. When /CS=”1”, there is no influence to the parallel interface.
Note2. “1” = VDDI level, “0” = DGND level.
IM0~IM3
Ver. 1.7
I
22
DGND/VDDI
MCU
MCU
MCU
MCU
MCU
MCU
MCU
DGND/VDDI
-
ST7781
6.3 Driver Output Pin
Name
I/O
Description
-Source driver output pins
-To change the shift direction of signal outputs, use the SS bit.
SS = “0”, the data in the RAM address “h00000” is output from S1.
SS = “1”, the data in the RAM address “h00000” is output from S720.
-When SS=”0”
S1, S4, S7, … display red (R), S2, S5, S8, ... display green (G), and S3, S6,
S9 ... display blue (B)
-Gate driver output pins.
VGH: Selecting Gate Lines Level.
VGL: Non-selecting Gate Lines Level.
-A reference voltage for step-up circuit 1.
The amplitude between VDD and AGND is determined by the VC [2:0]
bits.Make sure to set the VCI1 voltage so that the AVDD, VCL, VGH and
VGL voltages are set within the respective specification.
-Connect a capacitor for stabilization.
- Power pad for analogy circuit.
-Connect a capacitor for stabilization.
Connect Pin
S1 to S720
O
G1 to G320
O
VCI1
O
AVDD
O
VCL
O
-Power pad for VCOML circuit.
-Connect a capacitor for stabilization.
Capacitor
VGH
O
-Power pad pin for gate driver circuit.
-Connect a capacitor for stabilization.
Capacitor
VGL
O
-Power pad for gate driver circuit.
-Connect a capacitor for stabilization.
Capacitor
GVDD
O
-A standard level for grayscale voltage generator.
-Connect a capacitor for stabilization.
Capacitor
VCC
O
- Monitoring pin of internal digital reference voltage.
-Connect a capacitor for stabilization.
Capacitor
VCOMH
O
-Positive voltage output of VCOM.
-Connect a capacitor for stabilization.
Capacitor
VCOML
O
-Negative voltage output of VCOM.
-Connect a capacitor for stabilization.
Capacitor
VCOM
O
-A power supply for the TFT-LCD common electrode.
Common
Electrode
LCD
LCD
Capacitor
Capacitor
C11P, C11N
Step-Up
O
-Capacitor connecting pins for step-up circuit 1 (for AVDD).
C12P, C12N
Capacitor
C21P, C21N
Step-Up
O
-Capacitor connecting pins for step-up circuit 2 (for VGH, VGL, and VCL).
C22P, C22N
Capacitor
C23P, C23N
Note1.VCI1, GVDD, AVDD, VCC, VCL, VOMH, VOML, C11P/N, C12P/N, C21P/N pin need to connect a capacitor that
rated min voltage: 6.3v and typical capacitance value: 1uf
Note2.C22P/N, C23P /N, need to connect a Capacitor that rated min voltage: 10v and typical capacitance value: 1uf
Note3.VGH, VGL need to connect a Capacitor that rated min voltage: 25v and typical capacitance value: 1uf
6.4 Test Pin
Name
I/O
DUMMY
O
TESTO
O
TESTI
I
OSC
O
V25
O
Ver. 1.7
Description
-These pins are dummy (have no function inside).
-Please let these pin open.
-These pins are for testing.
-Please let these pin open.
-These pins are for testing.
-Please let these pin connect to DGND.
-This pin is for testing.
-Please let these pin open.
-This pin is for testing.
-Please let these pin open.
23
Connect Pin
Open
Open
DGND
Open
Open
ST7781
7. Driver Electrical Characteristics
7.1 Absolute Operation Range
Item
Symbol
Rating
Unit
Supply Voltage
VDD
- 0.3 ~ +4.6
V
Supply Voltage (Logic)
VDDI
- 0.3 ~ +4.6
V
Supply Voltage (Digital)
VCC
-0.3 ~ +4.6
V
Driver Supply Voltage
VGH-VGL
-0.3 ~ +30.0
V
Logic Input Voltage Range
VIN
0.5 ~ VDDI + 0.5
V
Logic Output Voltage Range
VO
0.5 ~ VDDI + 0.5
V
Operating Temperature Range
TOPR
-30 ~ +85
℃
Storage Temperature Range
TSTG
-40 ~ +125
℃
Note: If one of the above items is exceeded its maximum limitation momentarily, the quality of the product may be
degraded. Absolute maximum limitation, therefore, specify the values exceeding which the product may be
physically damaged. Be sure to use the product within the recommend range.
7.2 DC Characteristics
Parameter
Symbol
Condition
Min
Specification
TYP
Max
Unit
Power & Operation Voltage
System Voltage
VDD
Operating Voltage
2.5
2.8
3.3
Interface Operation
VDDI
I/O Supply Voltage
1.65
1.8/2.8
3.3
Voltage
Input / Output
Logic-High Input Voltage
VIH
0.7VDDI
VDDI
Logic-Low Input Voltage
VIL
VSS
0.3VDDI
Logic-High Output
VOH
IOH = -1.0mA
0.8VDDI
VDDI
Voltage
Logic-Low Output
VOL
IOL = +1.0mA
VSS
0.2VDDI
Voltage
Input Leakage Current
IIL
-0.1
+0.1
Source Driver
Output Deviation Voltage
VDEV
10
Output Offset Voltage
VOFFSET
35
Note 1: VDDI=1.65 to 3.3V, VDD=2.6 to 3.3V, AGND=DGND=0V, TA= -30 to 85℃.
Note 2: The maximum value is between measured point of source output and gamma setting value.
Related
Pins
V
V
V
V
Note 1
Note 1
V
Note 1
V
Note 1
uA
Note 1
mV
mV
Note 2
7.3 Power Consumption
Ta=25℃, Frame Rate = 70Hz,
Operation Mode
Inversion
Mode
Image
DC Current Consumption
Typical
Maximum
IDDI
IDD
IDDI
IDD
(mA)
(mA)
(mA)
(mA)
Normal Mode
One Line
Note 1
0.01
3.00
0.01
5.00
Stand-by Mode
N/A
Note 1
0.01
0.03
0.01
0.05
Note 1: VDDI=1.8V, VDD=2.8V, All pixels black.
.
Ver. 1.7
24
ST7781
8. System Interface
8.1 Interface Specifications
ST7781 has the system interface to read/write the control registers and display memory (DRAM) displaying a moving
picture. User can select an optimum interface to display the moving or still picture with efficient data transfer. All display
data are stored in the DRAM to reduce the data transfer efforts and only the updating data is necessary to be transferred.
User can only update a sub-range of DRAM by using the window address function.
ST7781 adopts 18-bit bus interface architecture for high-performance microprocessor. All the functional blocks of ST7781
starts to work after receiving the correct instruction from the external microprocessor by the 18bits, 16bits, 9bits,8bits. The
index register (IR) stores the register address to which the instructions and display data will be written. The data/command
selection signal (RS), the read/write signals (/RD//WR) and data bus DB[17:0] are used to read/write the instructions and
data of ST7781. The registers of the ST7781 are categorized into the following groups.
1. Specify the Index of Register (IR)
2. Read a Status
3. Display Control
4. Power Management Control
5. Display Data Processing
6. Set Internal DRAM Address (AC)
7. Transfer Data to/from the Internal DRAM (R22h)
8. Internal Grayscale γ-Correction (R30h ~ R3Dh)
Normally, the display data (DRAM) is most often updated, and in order since the ST7781 can update internal DRAM
address automatically as it writes data to the internal DRAM and minimize data transfer by using the window address
function, there are fewer loads on the program in the microprocessor.
Ver. 1.7
25
ST7781
8.2 Timing Chart
Parallel Interface Characteristics: 18, 16, 9 or 8-bits Bus (8080-Series MCU Interface)
VIH
/CS
VIL
VIH
RS
VIL
TAST
TWC
VIH
/WR
TWRL
TAHT
TWRH
VIL
TDST
Data Bus
Write
TDHT
VIH
VIL
TAHT
TAST
TRC
VIH
/RD
TRDL
VIL
TRDH
TODH
TRAT
VIH
Data Bus
Read
VIL
Fig. 8.2.1 Parallel Interface Timing Characteristics (8080-Series MCU Interface)
Signal
RS
/WR
/RD
DB[17:0]
Symbol
TAST
TAHT
TWC
TWRH
TWRL
TRC
TRDH
TRDL
TDST
TDHT
TRAT
TODH
VDDI=1.65 to 3.3V, VDD=2.5 to
Parameter
Min
Max
Address Setup Time
10
Address Hold Time (Write/Read)
5
Write Cycle
100
Control Pulse “H” Duration
50
Control Pulse “L” Duration
50
Read Cycle
300
Control Pulse “H” Duration
150
Control Pulse “L” Duration
150
Data Setup Time
10
Data Hold Time
15
Read Access Time
100
Output Disable Time
50
Table 8.2.1: Parallel Interface Characteristics
Fig. 8.2.2 Rising and Falling Timing for I/O Signal
Ver. 1.7
26
3.3V, AGND=DGND=0V, Ta=25 ℃
Unit
Description
ns
ns
ns
ns
ns
ns
ns
ns
TRAT, TRATFM: 3K ohm
ns
Pullup
or Down and 30pF
ns
Parallel Cap. To GND.
ns
TODH: 3K ohm Pullup or
ns
Down.
ST7781
Fig. 8.2.3 Write-to-Read and Read-to-Write Timing
Note: The rising time and falling time (Tr, Tf) of input signal and fall time are specified at 15 ns or less. Logic high and low
levels are specified as 30% and 70% of VDDI for Input signals.
Serial interface characteristics (3-line serial)
Fig. 8.2.4 3-line serial interface timing
Signal
/CS
SCL
SDI
SDO
Symbol
TCSS
TSCC
TSCYCW
TSHW
TSLW
TSCYCR
TSHR
TSLR
TSDS
TSDH
TSOD
TSOH
VDDI=1.65 to 3.3V, VDD=2.5 to 3.3V, AGND=DGND=0V, Ta=25 ℃
Parameter
Min
Max
Unit
Description
Chip select setup time
10
ns
Chip select hold time
50
ns
Serial clock cycle (Write)
100
ns
SCL “H” pulse width (Write)
40
ns
SCL “L” pulse width (Write)
40
ns
Serial clock cycle (Read)
200
ns
SCL “H” pulse width (Read)
100
ns
SCL “L” pulse width (Read)
100
ns
Data setup time
20
ns
Data hold time
20
ns
Data output setup time
100
ns
Data output hold time
5
ns
Table 8.2.2.: 3-line Serial Interface Characteristics
Note : The rising time and falling time (Tr, Tf) of input signal and fall time are specified at 15 ns or less. Logic high and low
levels are specified as 30% and 70% of VDDI for Input signals.
Ver. 1.7
27
ST7781
9. 8080 - Series MCU Parallel Interface
9.1 General Description
The MCU can use on of following interfaces: 11-lines with 8-bit parallel interface, 12-lines with 9-bit parallel interface,
19-lines with 16-bit parallel interface or 21-lines with 18-bit parallel interface. The chip-select /CS (active low)
enables/disables the parallel interface. RESET (active low) is an external reset signal to reset chip. /WR is the parallel data
write, /RD is the parallel data read and DB[17:0] is parallel data.
The LCD driver reads the data at the rising edge of /WR signal.Input The RS is the data/command flag. When RS=’1’, DB
[17:0] bits are either display data or command parameters. When RS =’0’, DB [17:0] bits are commands.
ST7781 supports high-speed system interfaces: i80-system high-speed interfaces to 8-, 9-, 16-, 18-bit parallel ports. The
interface mode is selected by setting the IM[3:0] pins.The interface functions of 8080-series parallel interface are given in
following table.
IM3
IM2
IM1
IM0
0
0
1
1
0
0
1
0
1
0
1
1
1
0
1
0
Interface
RS
/RD
/WR
Read Back Selection
0
1
↑
Write Command (DB[17:10])
1
1
↑
Write Display Data (DB[17:10])
8-bit
parallel
1
↑
1
Read Display Data (DB[17:10])
1
↑
1
Read Parameter or Status (DB[17:10])
0
1
↑
Write Command (DB[17:10], DB[8:1])
16-bit
1
1
↑
Write Display Data (DB[17:10], DB[8:1])
parallel
1
↑
1
Read Display Data (DB[17:10], DB[8:1])
1
↑
1
Read Parameter or Status (DB[17:10], DB[8:1])
0
1
↑
Write Command (DB[17:10])
9-bit
1
1
↑
Write Display Data (DB[17:9])
parallel
1
↑
1
Read Display Data (DB[17:9])
1
↑
1
Read Parameter or Status (DB[17:10])
0
1
↑
Write Command (DB[17:10], DB[8:1])
18-bit
1
1
↑
Write Display Data (DB[17:0])
parallel
1
↑
1
Read Display Data (DB[17:0])
↑
1
Read Parameter or Status (DB[17:10], DB[8:1])
1
Table 9.1: 8080 Series MCU Paraell Interface
ST7781 has a 16-bit index register (IR), an 18-bit write-data register (WDR), and an 18-bit read-data register (RDR). The IR
is the register to store index information from control registers and the internal DRAM. The WDR is the register to
temporarily store data to be written to control registers and the internal DRAM. The RDR is the register to temporarily store
data read from the DRAM. Data from the MPU to be written to the internal DRAM are first written to the WDR and then
automatically written to the internal DRAM in internal operation. Data are read via the RDR from the internal DRAM.
Therefore, invalid data are read out to the data bus when the ST7781 read the first data from the internal DRAM. Valid data
are read out after the ST7781 performs the second read operation. Registers are written consecutively as the register
execution time except starting oscillator takes 0 clock cycle.
Ver. 1.7
28
ST7781
9.2 8080-Series MCU Write Cycle Sequence
The write cycle means that the host writes information (command or/and data) to the display module via the interface. Each
write cycle (/WR “1” - “0” - “1” sequence) consists of 3 control signals (RS, /RD, /WR) and data signals (DB17:0]). RS bit is
a control signal, which tells if the data is a command or a data. The data signals are the command if the control signal is
“0” and vice versa it is data “1”.
Fig. 9.2 8080-Series /WR Protocol
Note: /WR is an unsynchronized signal (It can be stopped).
1- byte
Command
DB[17:0]
S
2- byte
Command
N- byte
Command
CMD
CMD
PA1
CMD
PA1
PAN-2
PAN-1
P
S
CMD
CMD
PA1
CMD
PA1
PAN-2
PAN-1
P
S
CMD
CMD
PA1
CMD
PA1
PAN-2
PAN-1
P
RESET “ 1 ”
/CS
RS
/RD
“1”
/WR
DB[17:0]
Host DB[17:0]
(Host to LCD)
Driver DB[17:0]
(LCD to Host)
Hi-Z
CMD: Write Command Code
PA: Parameter or Display Data
Signals on DB[17:0],RS,nWR,nRD
pins during nCS=1 are ignored
Fig. 9.2.1 8080-Series Parallel Bus Protocol, Write to Register or Display RAM
Ver. 1.7
29
ST7781
9.3 8080-18 bits Interface Write Data Format
The 8080-18bits interface is selected by setting the IM [3:0] =”1010”.This mode only 262k colors format in display. In this
interface write Instructions and DRAM method following figure.
/RST
MCU
RESET
/CS
/CS
A0
RS
/WR
/WR
/RD
/RD
D[17:0]
ST7781
DB[17:0]
18
Fig. 9.1.2 8080-18 bits Interface Data Format (Command Write/DRAM Write)
Ver. 1.7
30
ST7781
9.4 8080-16 bits Interface Write Data Format
The 8080-16bits interface is selected by setting IM [3:0] =”0010”.The mode can display 262k or 65k colors format. When the
262k color format is display, two transfers mode is used (first transfer: 2 bits, second transfer: 16 bits or first transfer: 16 bits,
second transfer: 2 bits)
Fig. 9.4 8080-16 bits Interface Data Format (Command Write/Display RAM Write)
Ver. 1.7
31
ST7781
9.5 8080-9bits Interface Write Data Format
The 8080-9bits interface is selected by setting the IM [3:0] = “1011” and the DB [17:9] pins are used to transfer the data. When
writing the 16-bit register, the data is divided into upper byte and lower byte and the upper byte is transferred first. The display
data is also divided in upper byte (9 bits) and lower byte, and the upper byte is transferred first. The unused DB [8:0] pins must
be tied to either VDDI or DGND.
/RST
MCU
RESET
/CS
/CS
A0
RS
/WR
/WR
/RD
/RD
ST7781
DB[17:9]
DB[8:0]
D[8:0]
9
Fig. 9.5 8080-9 bits Interface Data Format (Command Write/Display RAM Write)
Ver. 1.7
32
ST7781
9.6 8080-8bits Interface Write Data Format
The 8080 8-bit interface is selected by setting the IM [3:0] as “0011” and the DB [17:10] pins are used to transfer the data. The
mode can display 262k or 65k colors format. When writing the 16-bit register, the data is divided into upper byte lower byte and
the upper byte is transferred first. The display data is also divided in upper byte (8 bits) and lower byte, and the upper byte is
transferred first. The written data is expanded into 18 bits internally (see the figure below) and then written into DRAM. The
unused DB [9:0] pins must be tied to either VDDI or DGND.
Fig. 9.6 8080-8 bits interface data format (command write/Display RAM write)
Ver. 1.7
33
ST7781
9.7 8080-series MCU Read Cycle Sequence
The read cycle (/RD “1”- “0”- “1” sequence) means that the host reads information from display via interface. The driver sends
data (DB [17:0]) to the host when there is a falling edge of /RD and the host reads data when there is a rising edge of /RD.
Fig. 9.7 8080-Series /RD Protocol
Note: /RD is an unsynchronized signal (It can be stopped).
Fig. 9.7.1 8080-series parallel bus protocol, read data from register or display RAM
Ver. 1.7
34
ST7781
9.8 8080-18bits interface read data format
Fig. 9.8 8080-18 bits Interface Data Format (Command Read/Display RAM Read)
Ver. 1.7
35
ST7781
9.9 8080-16bits Interface Read Data Format
Fig. 9.9 8080-16 bits Interface Data Format (Command Read/Display RAM Read)
Ver. 1.7
36
ST7781
9.10 8080-9bits Interface Read Data Format
Fig. 9.10 8080-9 bits Interface Data Format (Command Read/Display RAM Read)
Ver. 1.7
37
ST7781
9.11 8080-8bits Interface Read Data Format
Fig.9.11 8080-8 bits Interface Data Format (Command Read/Display RAM Read)
Ver. 1.7
38
ST7781
DRAM Address map table of SS=1, BGR=1
S1
SS = ’0’
GS = ’0’
GS = ’1’
SS = ’1’
S2
S3
S4
S5
S6
S718 S719 S720 S715 S716 S717
BGR=’0’
R
G
B
R
G
B
BGR=’1’
B
G
R
B
G
R
“0000”h
“0000”h
G319
G2
X Address
“0000”h
“0001”h
Y Address
“0001”h
|
|
|
|
|
|
|
|
|
|
|
|
-------
S4
S5
S6
S1
S2
S3
-------
R
G
B
R
G
B
B
G
R
B
G
R
G2
G1
“00EE”h
“00EF”h
“0000”h
“0000”h
“00EE”h
“00EF”h
“0001”h
“0001”h
“0001”h
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
X Address
“0000”h
“0001”h
“00EE”h
“00EF”h
Y Address
“013E”h
“013E”h
“013E”h
“013E”h
G320
Y Address
X Address
“0000”h
“0001”h
“00EE”h
“00EF”h
Y Address
“013F”h
“013F”h
“013F”h
“013F”h
-------
-------
-------
-------
-------
Fig.9.12 DRAM Address Map Table
Note:
X Address Start Instruction：R50h
X Address End Instruction：R51h
Y Address Start Instruction：R52h
Y Address End Instruction：R53h
SS/GS Setting Instruction：R01h
BGR Setting Instruction：R03h
Ver. 1.7
S715 S716 S717 S718 S719 S720
G319
“0001”h
G1
“0000”h
G320
X Address
------
39
ST7781
10 Serial Peripheral Interfaces (SPI)
10.1 General Description
The serial interface is a 3-lines interface for communication between the micro controller and the LCD driver chip.That is
selected by setting IM [3:0] pins as “010X” level. The 3-lines serial use: /CS(chip enable), SCL (serial clock) , SDI (serial
data input)and SDO(serial data output). Serial clock (SCL) is used for interface with MCU only, so it can be stopped when
no communication is necessary. The DB [17:0] pins are not used, must be fixed at VDDI or DGND.The selections of this
interface see the Table
IM3
IM2
IM1
IM0
Interface
RS
/RD
/WR
0
1
0
ID
3-line serial interface
N/A
N/A
SCL
Read back selection
DB[17:0]: unused
Serial data input :SDI
Serial data output:SDO
Table 10.1 Serial Interface Type Selection
Note: Unused pins connected to VDDI.
The SPI interface operation enables from the falling edge of /CS and ends of data transfer on the rising edge of /CS. The
chip is selected when 6-bit device ID code in the start byte that be matched. Then ST7781 receive sub-sequent data that
starts taking. The least significant bit of device ID code is determined by setting the IM0 pin.Example:IM0=”0”, ST7781 is
selected when the device ID code=”011100” in the start byte. The seventh bit of start byte is RS bit and the eighth bit is
R/W bit. That two bit control ST7781 some operation that description see Table
Start Byte Format
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Device ID code
0
1
1
1
0
ID/IM0
RS and R/W Bit Function Description
Bit 7
Bit 8
RS
R/W
Function
RS
R/W
0
0
Set an index register
0/1
0/1
0
1
Read staus
1
0
Write a register or display RAM
1
1
Read a register
Table 10.1.1Start byte format and Bit [7:8] function description
10.2 Command Write Mode
The write mode of the interface means the micro controller writes commands to the LCD driver. Start byte data packet
contains a control bit RS to indicates transmission data format. If RS is “low”, the transmission byte is interpreted as a
command byte. If RS is “high”, the transmission byte is stored in the display data RAM (Memory write command), or
command register as parameter.
Any instruction can be sent in any order to the driver. The MSB is transmitted first. The serial interface is initialized when
/CS is “high”. In this state, SCL clock pulse or SDI data have no effect. A falling edge on /CS enables the serial interface
and indicates the start of data transmission. When /CS is “1”, SCL clock is ignored. During the high time of /CS the serial
interface is initialized. At the falling edge of /CS, SCL can be high or low. SDI is sampled at the rising edge of /CS. RS (Start
byte bit 7) indicates, whether the input data is command code (RS=’0’) or parameter/RAM data (RS=’1’).
Fig. 10.2 3-line serial interface write protocol
Ver. 1.7
40
ST7781
10.3 Read Functions
The read mode of the interface means that the micro controller reads register value from the driver. To do that the micro
controller first has to send a command and then the following start byte that setting read register operation (RS=”1”,
R/W=”1”).In reading from command register status, after receiving the start byte, ST7781 starts to transfer the data in unit
of byte and the data transfer starts from the MSB bit. All registers of ST7781 are 16-bit format and the first byte as upper
eight of data. .
Fig. 10.3.1 3-line Serial Protocol for read command register
Ver. 1.7
41
ST7781
11. Register Descriptions
ST7781 adopts 18-bit bus interface architecture for high-performance microprocessor. All the functional Blocks of ST7781
starts to work after receiving the correct instruction from the external microprocessor by the 18-, 16-, 9-, 8-bit interface. The
index register (IR) stores the register address to which the instructions and Display data will be written. The register
selection signal (RS), the read/write signals (/RD//WR) and data bus DB[17:0] are used to read/write the instructions and
data of ST7781. The registers of the ST7781 are categorized into the following groups.
1. Specify the index of register (IR)
2. Read a status
3. Display control
4. Power management Control
5. Graphics data processing
6. Set internal DRAM address (AC)
7. Transfer data to/from the internal DRAM (R22)
8. Internal grayscale γ-correction (R30 ~ R3D)
Normally, the display data (DRAM) is most often updated, and in order since the ST7781 can update internal DRAM
address automatically as it writes data to the internal DRAM and minimize data transfer by using the window address
function, there are fewer loads on the program in the microprocessor. The way of assigning data to the 16 register bits (
DB [15:0]) varies for each interface. Send registers in accordance with the following data transfer format.
Ver. 1.7
42
ST7781
11.1 Instruction Description
No
Registers
W/R
IR
Index Register
W
00h
Driver ID Code Read
R
01h
Driver Output Control
W
02h LCD Driving Wave Control W
03h
Entry Mode
W
04h
Resize Control
W
07h
Display Control 1
W
08h
Display control 2
W
09h
Display Control 3
W
0Ah
Display Control 4
W
0Dh Frame Marker Position
W
10h
Power Control 1
W
11h
Power Control 2
W
12h
Power Control 3
W
13h
Power Control 4
W
DRAM Horizontal Address
20h
W
Set
21h DRAM Vertical Address Set W
22h
Write Data to DRAM
W
22h Read Data from DRAM
R
29h
VCOMH Control
W
Frame Rate and Color
2Bh
W
Control
30h
Gamma Control 1
W
31h
Gamma Control 2
W
32h
Gamma Control 3
W
35h
Gamma Control 4
W
36h
Gamma Control 5
W
37h
Gamma Control 6
W
38h
Gamma Control 7
W
39h
Gamma Control 8
W
3Ch
Gamma Control 9
W
3Dh
Gamma Control 10
W
Horizontal Address Start
50h
W
Position
Horizontal Address End
51h
W
Position
Vertical Address Start
52h
W
Position
Vertical Address End
53h
W
Position
60h
Gate Scan Control 1
W
61h
Gate Scan Control 2
W
Partial Image 1 Display
80h
W
Position
81h
82h
83h
84h
85h
90h
92h
D2h
D9h
Partial Image 1 Start
Address
Partial Image 1 End
Address
Partial Image 2 Display
Position
Partial Image 2 Start
Address
Partial Image 2 End
Address
Panel Interface Control 1
Panel Interface Control 2
EEPROM ID Code
EEPROM Control Status
DFh EEPROM Wite Command
FAh
FEh
FFh
EEPROM Enable
EEPROM VCOM Offset
FAh/FEh Enable
Ver. 1.7
RS
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
D15
0
0
0
TRI
0
0
0
0
0
0
0
0
0
0
D14
1
0
0
DFM
0
0
FP6
0
0
0
0
0
0
0
D13
1
0
0
0
0
PTDE1
FP5
0
0
0
0
0
0
0
D12
1
0
0
BGR
0
PTDE0
FP4
0
0
0
SAP
0
0
VDV4
D11
0
0
0
0
0
0
FP3
0
0
0
0
0
0
VDV3
D10
1
SM
1
0
0
0
FP2
PTS2
0
0
BT2
DC12
0
VDV2
D9
1
0
BC0
HWM
RCV1
1
0
0
0
0
0
0
0
0
AD7
AD6
AD5
AD4
AD3
1
1
1
1
0
0
0
0
0
0
0
AD16
AD15
AD14
AD13
AD12
AD11
0
0
0
0
0
0
0
0
0
0
VCM5
VCM4
VCM3
1
0
0
0
0
0
0
0
0
0
0
0
0
FRS3
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VRP1[4]
0
0
0
0
VRN1[4]
0
0
0
0
VRP1[3]
0
0
0
0
VRN1[3]
KP1[2]
KP3[2]
KP5[2]
RP1[2]
VRP1[2]
KN1[2]
KN3[2]
KN5[2]
RN1[2]
VRN1[2]
KP1[1]
KP3[1]
KP5[1]
RP1[1]
VRP1[1]
KN1[1]
KN3[1]
KN5[1]
RN1[1]
VRN1[1]
KP1[0]
KP3[0]
KP5[0]
RP1[0]
VRP1[0]
KN1[0]
KN3[0]
KN5[0]
RN1[0]
VRN1[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VRP0[3]
0
0
0
0
VRN0[3]
KP0[2]
KP2[2]
KP4[2]
RP0[2]
VRP0[2]
KN0[2]
KN2[2]
KN4[2]
RN0[2]
VRN0[2]
1
0
0
0
0
0
0
0
0
HSA7
HSA6
HSA5
HSA4
HSA3
HSA2
HSA1
HSA0
1
0
0
0
0
0
0
0
0
HEA7
HEA6
HEA5
HEA4
HEA3
HEA2
HEA1
HEA0
1
0
0
0
0
0
0
0
VSA8
VSA7
VSA6
VSA5
VSA4
VSA3
VSA2
VSA1
VSA0
1
0
0
0
0
0
0
0
VEA8
VEA7
VEA6
VEA5
VEA4
VEA3
VEA2
VEA1
VEA0
1
1
GS
0
0
0
NL5
0
NL4
0
NL3
0
NL2
0
NL1
0
NL0
0
0
0
0
0
SCN5
0
SCN4
0
SCN3
0
SCN2
NDL
SCN1
VLE
FP1
PTS1
0
0
BT1
DC11
0
VDV1
D8
1
SS
EOR
0
RCV0
BASEE
FP0
PTS0
0
FMP8
BT0
DC10
0
VDV0
D7
ID7
1
0
0
0
0
0
0
0
0
FMP7
APE
0
VCIRE
0
D6
ID6
0
0
0
0
0
0
BP6
0
0
FMP6
AP2
DC02
0
0
D5
ID5
0
0
0
I/D1
RCH1
GON
BP5
PTG1
0
FMP5
AP1
DC01
0
0
D4
ID4
0
0
0
I/D0
RCH0
DTE
BP4
PTG0
0
FMP4
AP0
DC00
0
0
D3
ID3
0
0
0
AM
0
CL
BP3
ISC3
FMARKOE
FMP3
0
0
VRH3
0
D1
ID1
1
0
0
0
RSZ1
D1
BP1
ISC1
FMI1
FMP1
STB
VC1
VRH1
0
D0
ID0
1
0
0
0
RSZ0
D0
BP0
ISC0
FMI0
FMP0
0
VC0
VRH0
0
AD2
AD1
AD0
AD10
AD9
AD8
VCM2
VCM1
VCM0
FRS2
FRS1
FRS0
DRAM Write Data (WD17-0) / Read Data (RD17-0)
1
0
0
0
0
0
0
0
PTDP08
PTDP07
PTDP06
PTDP05
PTDP04
PTDP03
W
1
0
0
0
0
0
0
0
PTSA08
PTSA07
PTSA06
PTSA05
PTSA04
PTSA03
W
1
0
0
0
0
0
0
0
PTEA08
PTEA07
PTEA06
PTEA05
PTEA04
PTEA03
W
1
0
0
0
0
0
0
0
PTDP18
PTDP17
PTDP16
PTDP15
PTDP14
PTDP13
W
1
0
0
0
0
0
0
0
PTSA18
PTSA17
PTSA16
PTSA15
PTSA14
PTSA13
W
1
0
0
0
0
0
0
0
PTEA18
PTEA17
PTEA16
PTEA15
PTEA14
PTEA13
W
W
W
W
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
NOWI2
0
0
0
DIVI1
NOWI1
0
0
0
DIVI0
NOWI0
0
0
0
0
0
0
0
EE_IB7
RTNI6
0
ID6
ID_EN
EE_IB6
RTNI5
0
ID5
VCM_EN
EE_IB5
RTNI4
0
ID4
0
EE_IB4
RTNI3
0
ID3
0
EE_IB3
W
1
0
0
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
W
W
D2
ID2
0
0
0
0
0
0
BP2
ISC2
FMI2
FMP2
0
VC2
VRH2
0
43
EE_CMD7 EE_CMD6 EE_CMD5 EE_CMD4 EE_CMD3
1
0
0
0
0
0
0
0
1
0
0
0
0
0
VCMF4
0
0
0
VCMF3
0
KP0[1]
KP0[0]
KP2[1]
KP2[0]
KP4[1]
KP4[0]
RP0[1]
RP0[0]
VRP0[1] VRP0[0]
KN0[1]
KN0[0]
KN2[1]
KN2[0]
KN4[1]
KN4[0]
RN0[1]
RN0[0]
VRN0[1] VRN0[0]
SCN0
REV
PTDP0
PTDP02 PTDP01
0
PTSA0
PTSA02 PTSA01
0
PTEA0
PTEA02 PTEA01
0
PTDP1
PTDP12 PTDP11
0
PTSA1
PTSA12 PTSA11
0
PTEA1
PTEA12 PTEA11
0
RTNI2
RTNI1
RTNI0
0
0
0
ID2
ID1
ID0
0
0
0
EE_IB2
EE_IB1 EE_IB0
EE_CMD
EE_CMD2 EE_CMD1
0
1
0
1
0
MTPPROG
0
VCMF2
VCMF1 VCMF0
0
0
FXEN
ST7781
11.1.1 Index (IR)
Index(IR)
RS
0
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
↑
1
-
-
-
-
-
-
-
-
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
Note: “-“Don’t care
Description
The index register specifies the index R00h to RFFh of the control register or RAM control to be accessed. The
access to the register and instruction bits in it is prohibited unless the index is specified in the index register.
11.1.2 Device ID Code Read (R00h)
Device ID Code Read Out (R00h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
1
↑
0
1
1
1
0
1
1
1
1
0
0
0
0
0
1
1
Description
When read this register, the device output device ID code
11.1.3 Device Output Control (R01H)
Device Output Control (R01H)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
SM
0
SS
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
SS: Select the shift direction of outputs from the source driver.
When SS = 0, the shift direction of outputs is from S1 to S720
When SS = 1, the shift direction of outputs is from S720 to S1.
In addition to the shift direction, the settings for both SS and BGR bits are required to change the Assignment of R, G,
B dots to the source driver pins.
To assign R, G, B dots to the source driver pins from S1 to S720, set SS = 0.
To assign R, G, B dots to the source driver pins from S720 to S1, set SS = 1.
Note: When changing SS or BGR bits, DRAM data must be rewritten.
SM: Sets the gate driver pin arrangement in combination with the GS bit (R60h) to select the optimal scan mode for
the module.
Description
SM
GS
0
0
Scan Direction
Gate Output Sequence
G1,G2,G3,G4…..,G316
G317,G318,G319, G320
Ver. 1.7
44
ST7781
G320,G319,…...…G316
0
1
G7,G6,G5,G4,G3,G2,G1
G1,G3,G5….……G311
G313,G315,G317,G319
1
0
G2,G4,G6….……G312
G314,G316,G318,G320
G320,G318,….…..G14
G12,G10,G8,G6,G4,G2
1
1
G319,G317….….G13
G11,G9,G7,G5,G3,G1
11.1.4 LCD Driving Wave Control (R02h)
LCD Driving Wave Control (R02h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
1
B/C
EOR
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
Default value
Description
Ver. 1.7
B/C: VCOM Driving Wave Control.
When B/C = 0, the frame/field inversion is selected
When B/C = 1 and EOR=1, the line inversion is selecte.
45
ST7781
11.1.5 Entry Mode (R03h)
Entry Mode (R03h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
TRI
DFM
0
BGR
0
0
HWM
0
0
0
I/D1
I/D0
AM
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
Default value
AM: Sets the DRAM Updata Direction
When AM = “0”, set the horizontal writing direction.
When AM = “1”, set the vertical writing direction.
When a window area is set by registers R50h ~R53h, only the addressed DRAM area is updated based on I/D [1:0]
and AM bits setting.
I/D [1:0]: Control the address counter (AC) to automatically increase or decrease by 1 when update one pixel display
data.
Description
Ver. 1.7
AM
ID[1:0]
0
Write DRAM Direction
AM
ID[1:0]
00
1
00
0
01
1
01
0
10
1
10
0
11
1
11
46
Write DRAM Direction
ST7781
HWM: The ST7781 writes data in high speed with low power consumption by setting HWM = 1. The data to be written
within the window address area is buffered in order to write the data in units of horizontal lines. This can
minimize the Number of RAM access and the power consumption required in data write operation.
When HWM = 1, make sure to set AM = 0 (horizontal direction) and write the data in each horizontal line of the
window address area at a time. If the data is not enough to rewrite the horizontal line of the window address
area, the DRAM data in that line is not overwritten.
Notes1: The ST7781 requires no dummy write operation in high-speed write operation.
Note 2. When terminating DRAM data write operation in the middle of the line and executing another instruction, the
data in the buffer is cleared.
BGR: Reverses the order from RGB to BGR in writing 18-bit pixel data in the DRAM.
BGR = 0: Write data in the order of RGB to the DRAM.
BGR=0
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
R5
R4
R3
R2
R1
R0
G5
G4
G3
G2
G1
G0
B5
B4
B3
B2
B1
B0
BGR = 1: Reverse the order from RGB to BGR in writing data to the DRAM.
BGR=1
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
B5
B4
B3
B2
B1
B0
G5
G4
G3
G2
G1
G0
R5
R4
R3
R2
R1
R0
TRI: When TRI = “1”, data are transferred to the internal DRAM in 8-bit x 3 transfers mode via the 8-bit interface.It is
also possible to send data via the 16-bit interface in the transfer mode that realizes display in 262k colors in
combination with DFM bits. When not using these interface modes, be sure to set TRI = “0”.
DFM: Set the mode of transferring data to the internal RAM when TRI = “1”.
Ver. 1.7
TRI
DFM
0
*
1
0
1
1
8080-16bits Interface Color Format
47
ST7781
TRI
DFM
0
*
1
0
1
1
8080-8bits Interface Color Format
11.1.6 Resizing Control (R04h)
Resizing Control (R04h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
1
↑
1
0
0
0
0
0
0
Default value
0
0
0
0
0
D9
D8
RCV
RCV
0
1
0
0
0
D7
D6
D5
0
0
RCH1
D4
D3
D2
0
0
RCH
0
0
0
0
0
0
0
D1
D0
RSZ
RSZ
1
0
0
0
RSZ [1:0]: Sets the resizing factor. When the RSZ [1:0] are set for resizing, the ST7781 writes the data according to
the resizing factor so that the original image is displayed in horizontal and vertical dimensions contracted
according to the factor.
Description
Ver. 1.7
RSZ1
RSZ0
Resizing Scale
0
0
No Resizing ( X1 )
0
1
X 1/2
1
0
Setting Inhibited
1
1
X1/4
48
ST7781
RCH [1:0]: Sets the number of pixels made as the remainder in horizontal direction when resizing a picture. By
specifying the number of remainder pixels with RCH [1:0] the data can be transferred without taking the
reminder pixels into consideration. Make sure that RCH [1:0] = “00” when not using the resizing function
(RCH [1:0]=”00”) or there are no remainder pixels.
RCH1
RCH0
Number of Remainder Pixels in Horizontal Direction
0
0
0 Pixel
0
1
1 Pixel
1
0
2 Pixel
1
1
3 Pixel
RCV [1:0]: Sets the number of pixels made as the remainder in vertical direction when resizing a picture.By
specifying the number of remainder pixels with the RCV bits, the data can be transferred without taking
the reminder pixels into consideration. Make sure that RCV [1:0] =”00 “when not using the resizing
function RCV [1:0] =”00 “or there are no remainder pixels.
RCV1
RCV0
Number of Remainder Pixels in Vertical Direction
0
0
0 Pixel
0
1
1 Pixel
1
0
2 Pixel
1
1
3 Pixel
11.1.7 Display Control 1 (R07h)
Display Control 1 (R07h)
RS
/WR
/RD
D15
D14
1
↑
1
0
0
Default value
0
0
D13
D12
PTD
PTD
E1
E0
0
0
D11
D10
D9
0
0
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
GON
DTE
CL
0
D1
D0
0
0
0
0
0
0
0
0
BAS
EE
0
0
0
0
D [1:0]: A graphics display is turned on the screen when writing D1 = “1”, and is turned off when writing D1 = “0”.
When writing D1 = “0”, the graphics display data is retained in the internal DRAM and the ST7781 displays
the data when writing D1 = “1”. When D1 = “0”, i.e. while no display is shown on the panel, all source outputs
becomes the GND level to reduce charging/discharging current, which is generated within the LCD while
driving liquid crystal with AC voltage.
When the display is turned off by setting D [1:0] =00, the ST7781’s internal display operation is halted completely. In
combination with the GON setting, the D [1:0] setting controls display ON/OFF.
Description
D1
0
0
1
1
1
D0
0
1
0
1
1
BASEE
0
1
0
0
1
Source,VCOM Output
GND
GND
Non-lit display
Non-lit display
Base Image display
Internal Operation
Halt
Operate
Operate
Operate
Operate
Note1: Data write operation from the microcontroller is performed irrespective of the setting of D [1:0] bits.
Note2: The D [1:0] setting is valid on both 1st and 2nd displays.
Ver. 1.7
49
ST7781
Note3: The non-lit display level from the source output pins is determined by instruction (PTS).
CL: When CL = “1”, the ST7781 halt grayscale amplifiers to display 8-color with low power consumption. When
setting 8-color display mode, follow the sequence of 8-color display mode setting.
CL
Display color
0
262,144
1
8
Note: When CL = 1, do not write the data corresponding to the grayscales, for which the operation of
amplifier is halted.
GON, DTE: The combination of GON and DTE settings set the output level form gate lines (G1 ~ G320).
GON
0
0
1
1
DTE
0
1
0
1
Gate Output
VGH
VGH
VGL
Normal display
BASEE: Base image display enable bit.
BASEE = 0: No base image is displayed. The ST7781 drives liquid crystal with non-lit display level or drives
only partial image display areas.
BASEE = 1: A base image is displayed on the screen.
PTDE [1:0]: Partial image 2 and Partial image 1 enable bits
PTDE1/0 = 0: turns off partial image. Only base image is displayed.
PTDE1/0 = 1: turns on partial image.
Ver. 1.7
50
ST7781
11.1.8 Display Control 2 (R08h)
Display Control 2 (R08h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
FP6
FP5
FP4
FP3
FP2
FP1
FP0
0
BP6
BP5
BP4
BP3
BP2
BP1
BP0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Description
FP[6:0]
BP[6:0]
7’h00
Setting Prohibited
7’h01
Setting Prohibited
7’h02
2 lines
7’h03
3 lines
7’h04
4 lines
7’h05
5 lines
7’h06
6 lines
7’h07
7 lines
7’h08
8 lines
7’h09
9 lines
7’h0A
10 lines
7’h0B
11 lines
:
:
7’h7D
125 lines
7’h7E
126 lines
7’h7F
127 lines
Porch Lines
FP [6:0]: Sets the number of lines for a front porch period (a blank period
following the end of display).
BP [6:0]: Sets the number of lines for a back porch period (a blank period
made before the beginning of display).
Note:IN 8080 interface operation mode, BP>=2 lines, FP>=2 lines
In external display interface operation, a back porch (BP) period starts on
the falling edge of the FMARK signal and the display operation starts after
the back porch period. A blank period will start after a front porch (FP)
period and it will continue until next FMARK input is detected.
Back Porch
FMARK
Default value
Display Area
Front Porch
Note:The output timing to the LCD is delayed by
2 lines period from the input FMARK signal.
Ver. 1.7
51
ST7781
11.1.9 Display Control 3 (R09h)
Display Control 3 (R09h)
RS
/WR
/RD
D15
D14
D13
D12
D11
1
↑
1
0
0
0
0
0
Default value
0
0
0
0
D10
D9
D8
PTS
PTS
PTS
0
2
1
0
0
0
0
D7
D6
0
0
0
0
D5
D4
D3
D2
D1
D0
PTG
PTG
ICS
ICS
ICS
ICS
1
0
3
2
1
0
0
0
0
0
0
0
ICS [3:0]: Set the scan cycle when PTG [1:0] selects interval scan in non-display area drive period. The scan cycle is
defined by n frame periods, where n is an odd number from 0 to 29. The polarity of liquid crystal drive
voltage from the gate driver is inverted in the same timing as the interval scan cycle.
Description
ICS[3:0]
Scan Cycle
fFLM = 60Hz
0000
0 frame
-
0001
1 frame
17ms
0010
3 frame
50ms
0011
5 frame
84ms
0100
7 frame
117ms
0101
9 frame
150ms
0110
11 frame
184ms
0111
13 frame
217ms
1000
15 frame
251ms
1001
17 frame
284ms
1010
19 frame
317ms
1011
21 frame
351ms
1100
23 frame
384ms
1101
25 frame
418ms
1110
27 frame
451ms
1111
29 frame
484ms
PTG [1:0]: Sets the scan mode in non-display area. The scan mode selected by PTG [1:0] bits is applied in the
non-display area when the base image is turned off and the non-display area other than the first and
second partial display areas.
PTG[1:0]
Gate Output in Non-Display Area
Source Output in Non-Display Area
VCOM Output
00
Normal Scan
Set with the PTS[2:0]
VCOMH/VCOML
01
Setting Prohibited
-
-
10
Interval Scan
Set with the PTS[2:0]
VCOMH/VCOML
11
Setting Prohibited
0
-
PTS [2:0]: Sets the source output level in non-display area drive period. When PTS[2] = 1, the operation of amplifiers
which generates the grayscales other than V0 and V63 are halted and the step-up clock frequency
becomes half the normal frequency in non-display drive period in order to reduce power consumption.
Grayscale
Source Output Level
PTS[2:0]
Step-Up Clock Frequency
Amplifier
Positive Polarity
Negative Polarity
in Operation
000
V63
V0
V63 to V0
Register Setting (DC1,DC0)
001
Setting inhibited
Setting inhibited
-
-
010
GND
GND
V63 to V0
Register Setting(DC1,DC0)
011
Hi-Z
Hi-Z
V63 to V0
Register Setting(DC1,DC0)
100
V63
V0
V63 and V0
Frequency setting by(DC1,DC0)
101
Setting inhibited
Setting inhibited
-
-
110
GND
GND
V63 and V0
Frequency setting by(DC1,DC0)
111
Hi-Z
Hi-Z
V63 and V0
Frequency setting by (DC1,DC0)
Note1: The power efficiency improved by halting grayscale amplifiers and slowing down the step-up clock frequency
can be obtained in non-display drive period.
Ver. 1.7
52
ST7781
Note2: The gate output level in non-display drive period is controlled by the PTG setting (off-scan mode).
11.1.10 Display Control 4 (R0Ah)
Display Control 4 (R0Ah)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
FMARKOE
FMI2
FMI1
FMI0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
FMARKOE: When FMARKOE = 1, the ST7781 starts outputting FMARK signal from the FMARK pin in the output
interval set by FMI[2:0] bits
FMI [2:0]: Sets the output interval of FMARK signal according to the display data rewrite cycle and data transfer rate.
FMI[2:0]
000
001
011
101
Others
Description
Output Interval
1 Frame
2 Frame
4 Frame
6 Frame
Setting Prohibited
11.1.11 Frame Marker Position (R0Dh)
Frame Marker Position (R0Dh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
FMP8
FMP7
FMP6
FMP5
FMP4
FMP3
FMP2
FMP1
FMP0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
FMP [8:0]: Sets the output position of frame cycle signal (frame marker). When FMP[8:0] = 9’h000, a high-active
pulse FMARK is output at the start of back porch period for 1H period. FMARK can be used as the
trigger signal for frame synchronous write operation.
Description
Ver. 1.7
FMP[8:0]
9’h000
9’h001
9’h002
9’h003
FMARK Output Position
0th line
1st line
2nd line
3rd line
.
.
.
.
.
.
9’h174
9’h175
9’h176
9’h177
372th line
373th line
374th line
375th line
53
ST7781
11.1.12 Power Control 1 (R10h)
Power Control 1 (R10h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
SAP
0
BT2
BT1
BT0
APE
AP2
AP1
AP0
0
0
STB
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
SAP: Source Driver output control
SAP=”0”, Source driver is disabled.
SAP=”1”, Source driver is enabled.
When starting the charge-pump of LCD in the Power ON stage, make sure that SAP=”0”, and set the SAP=”1”,
after starting up the LCD power supply circuit.
BT [2:0]: Sets the factor used in the step-up circuits.
Select the optimal step-up factor for the operating voltage. To reduce power consumption, set a smaller
factor.
BT[2:0]
AVDD
VCL
VGH
VGL
0
Vci1X2
-Vci1
-Vci1X5
Vci1X6
1
-Vci1X4
Vci1X2
-Vci1
2
-Vci1X3
3
-Vci1X5
Vci1X2
-Vci1
Vci1X5
4
-Vci1X4
5
-Vci1X3
6
-Vci1X4
Vci1X2
-Vci1
Vci1X4
7
-Vci1X3
Note1: Connect capacitors to the capacitor connection pins when generating AVDD, VGH, VGL and VCL
levels.
Note2: Make sure AVDD = 6.0V (max.), VGH = 15.0V (max.), VGL = – 12.5V (max) and VCL= -3.0V (max.)
Description
APE: Power supply enable bit. Set APE = “1” to start generation of power supply according to the power supply
startup sequence.
AP [2:0]: Adjusts the constant current in the operational amplifier circuit in the LCD power supply circuit. The larger
constant current enhances the drivability of the LCD, but it also increases the current consumption. Adjust
the constant current taking the trade-off into account between the display quality and the current
consumption. In no-display period, set AP[2:0]= “000” to halt the operational amplifier circuits and the
step-up circuits to reduce current consumption.
AP[2:0]
000
001
010
011
100
101
110
111
Gamma Driver Amplifier
Halt
1.5
1.25
1.00
0.75
0.5
0.25
Setting Prohibited
Source Driver Amplifier
Halt
1.5
1.25
1.00
0.75
0.5
0.25
Setting Prohibited
STB: When STB = “1”, ST7781 enters the standby mode and the display operation stops except the DRAM power
supply to reduce the power consumption. No change to the DRAM data and instruction setting is accepted and
he DRAM data and the instruction setting are maintained in STB mode.
Ver. 1.7
54
ST7781
11.1.13 Power Control 2 (R11h)
Power Control 2 (R11h)
RS
/WR
/RD
D15
D14
D13
D12
D11
1
↑
1
0
0
0
0
0
Default value
0
0
0
0
D10
D9
D8
DC1
DC1
DC1
0
D7
D6
D5
D4
DC0
DC0
DC0
0
2
1
0
1
1
1
0
D3
D2
1
0
1
1
1
D0
VC1
VC0
0
0
VC
0
2
D1
2
0
0
DC0 [2:0]: Selects the operating frequency of the step-up circuit 1. The higher step-up operating frequency enhances
the drivability of the step-up circuit and the quality of display but increases the current consumption.
Adjust the frequency taking the trade-off between the display quality and the current consumption into
account.
DC1 [2:0]: Selects the operating frequency of the step-up circuit 2. The higher step-up operating frequency enhances
the drivability of the step-up circuit and the quality of display but increases the current consumption.
Adjust the frequency taking the trade-off between the display quality and the current consumption into
account.
Step-Up Circuit 1
Description
DC0[2:0]
000
001
010
011
100
101
110
111
Note: Be sure
Step-Up Circuit 2
Step-Up Frequency ( fDCDC1 )
DC1[2:0]
Step-Up Frequency ( f DCDC2 )
Fosc/4
Fosc/8
Fosc/16
Fosc/32
Fosc/64
Fosc/128
Fosc/256
Halt step-up circuit 1
000
001
010
011
100
101
110
111
Fosc/8
Fosc/16
Fosc/32
Fosc/64
Fosc/128
Fosc/256
Fosc/512
Halt step-up circuit 2
fDCD1 ≥ fDCDC2 when setting DC0[2:0] and DC1[2:0]
VC [2:0] Sets the ratio factor of VDD to generate the reference voltages Vci1.
VC[2:0]
000
001
010
011
100
101
110
111
Ver. 1.7
Vci1 voltage
0.95 X VDD
0.90 X VDD
0.85 X VDD
0.80 X VDD
0.75 X VDD
0.70 X VDD
Disable
1.0 X VDD
55
ST7781
11.1.14 Power Control 3 (R12h)
Power Control 3 (R12h)
RS
/WR
D1
D1
D1
D1
D1
D1
5
4
3
2
1
0
0
0
0
0
0
0
/RD
D9
D8
0
0
D7
D6
D5
0
0
D4
VCIR
1
↑
1
0
0
0
0
0
0
0
0
1
0
0
D2
D1
D0
VRH
VRH
VRH
VRH
3
2
1
0
0
0
0
0
0
E
Default value
D3
0
VCIRE: Select the external reference voltage VDD or internal reference voltage VCIR.
When VCIRE=”0” using external reference voltage
When VCIRE=”1” using internal reference voltage 2.5V
VRH [3:0]:Set the amplifying rate (1.6 ~ 2.4) of VDD applied to output the GVDD level, which is a reference level for
the VCOM level and the grayscale voltage level.
Description
Ver. 1.7
VCIRE=0
VCIRE=1
VRH[3:0]
GVDD
VRH[3:0]
GVDD
0000
Halt
0000
Halt
0001
VDDX 2.00
0001
2.5V X 2
0010
VDDX 2.05
0010
2.5V X 2.05
0011
VDDX 2.10
0011
2.5V X 2.1
0100
VDDX 2.20
0100
2.5V X 2.2
0101
VDDX 2.30
0101
2.5V X 2.3
0110
VDDX 2.40
0110
2.5V X 2.4
0111
VDDX 2.40
0111
2.5V X 2.4
1000
VDDX 1.60
1000
2.5V X 1.6
1001
VDDX 1.65
1001
2.5V X1.65
1010
VDDX 1.70
1010
2.5V X 1.7
1011
VDDX 1.75
1011
2.5V X 1.75
1100
VDDX 1.80
1100
2.5V X 1.8
1101
VDDX 1.85
1101
2.5V X 1.85
1110
VDDX 1.90
1110
2.5V X 1.9
1111
VDDX 1.95
1111
2.5V X 1.95
Note1: When VDD<2.5V, internal reference voltage will be same as VCI.
Note2: Make sure VDD >= 2.6V, when using VCIRE =1.
Note3: Make sure that VC and VRH setting restriction: GVDD <=(AVDD-0.5)V
56
ST7781
11.1.15 Power Control 4 (R13h)
Power Control 4 (R13h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
VDV4
VDV3
VDV2
VDV1
VDV0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
1
1
1
0
0
0
0
Default value
VDV [4:0]: Selects the factor of GVDD to set the amplitude of VCOM alternating voltage from 0.70 to 1.24.
VDV[4:0]
VCOM Amplitude
VDV[4:0]
00000
GVDD X 0.70
10000
00001
GVDD X 0.72
10001
00010
GVDD X 0.74
10010
00011
GVDD X 0.76
10011
00100
GVDD X 0.78
10100
00101
GVDD X 0.80
10101
00110
GVDD X 0.82
10110
00111
GVDD X 0.84
10111
01000
GVDD X 0.86
11000
01001
GVDD X 0.88
11001
01010
GVDD X 0.90
11010
01011
GVDD X 0.92
11011
01100
GVDD X 0.94
11100
01101
GVDD X 0.96
11101
01110
GVDD X 0.98
11110
01111
GVDD X 1.00
11111
Note :Set VDV[4:0] to let VCOM amplitude less than 6V
Description
VCOM Amplitude
GVDD X 1.02
GVDD X 1.04
GVDD X 1.06
GVDD X 1.08
GVDD X 1.10
GVDD X 1.12
GVDD X 1.14
GVDD X 1.16
GVDD X 1.18
GVDD X 1.20
GVDD X 1.22
GVDD X 1.24
GVDD X 1.24
GVDD X 1.24
GVDD X 1.24
GVDD X 1.24
11.1.16 DRAM Horizontal/Vertical Address Set (R20h, R21h)
DRAM Horizontal/Vertical Address Set (R20h,R21h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
AD16
AD15
AD14
AD13
AD12
AD11
AD10
AD9
AD8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
1
↑
1
Default value
AD [16:0]: A DRAM address set initially in the AC (Address Counter). The address in the AC is automatically
updated according to the combination of AM, I/D[1:0] settings as the ST7781 writes data to the internal
DRAM so that data can be written consecutively without resetting the address in the AC.
Description
Ver. 1.7
AD[16:0]
17’h00000~17’h000EF
17’h00100~17’h001EF
17’h00200~17’h002EF
17’h00300~17’h003EF
.
.
.
17’h13D00~17’h13DEF
17’h13E00~17’h13EEF
17’h13F00~17’h13FFE
DRAM Data Map
1st line DRAM Data
nd
2 line DRAM Data
rd
3 line DRAM Data
th
4 line DRAM Data
.
.
.
th
318 line DRAM Data
th
319 line DRAM Data
h
320 line DRAM Data
57
ST7781
11.1.17 Write Data to DRAM (R22h)
Write Data to DRAM (R22h)
RS
/WR
/RD
1
↑
1
Description
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
WD [17:0] - DRAM Write Data
WD [17:0]: The ST7781 develops data into 18 bits internally in write operation. The format to develop data into 18
bits is different in different interface operation. The DRAM data represents the grayscale level. The
DRAM data represents the grayscale level. ST7783 automatically updates the address to the begin point
according to AM and I/D[1:0] settings as it’s wrote this register. The DFM bit sets the format to develop
16-bit data into the 18-bit data in 16-bit or 8-bit interface operation.
11.1.18 Read Data from DRAM (R22h)
Read Data from DRAM (R22h)
RS
/WR
/RD
1
1
↑
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
RD [17:0] - DRAM Read Data
RD [17:0]: 18-bit data read from the DRAM. RAM read data RD [17:0] is transferred via different data bus in different
interface operation. When the ST7781 reads data from the DRAM to the microcomputer, the first word
read immediately after RAM address set is executed is taken in the internal read-data latch and invalid
data is sent to the data bus. Valid data is sent to the data bus when the ST7781 reads out the second and
subsequent words. When either 8-bit or 16-bit interface is selected, the LSBs of R and B dot data are not
read out.
Description
Ver. 1.7
58
ST7781
The ST7781 also support function that automatically updates the address according to AM and I/D[1:0] settings as it
read data continuously address in the DRAM
11.1.19 VCOMH Control (R29h)
VCOMH Control (R29h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
0
VCM5
VCM4
VCM3
VCM2
VCM1
VCM0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
VCM [5:0]: Sets a factor of GVDD from 0.685 to 1.00 to generate the VCOMH voltage (Higher level of VCOM
alternating voltage). VCOMH voltage can be set either by internal electronic volume or external resistor.
Set the VCMR bit to select either external resistor or internal electronic volume for VCOMH adjustment.
Description
Ver. 1.7
VCM[5:0]
000000
000001
000010
000011
000100
000101
000110
000111
001000
001001
001010
001011
001100
001101
001110
001111
010000
010001
010010
010011
010100
010101
VCOMH
GVDD X 0.685
GVDD X 0.690
GVDD X 0.695
GVDD X 0.700
GVDD X 0.705
GVDD X 0.710
GVDD X 0.715
GVDD X 0.720
GVDD X 0.725
GVDD X 0.730
GVDD X 0.735
GVDD X 0.740
GVDD X 0.745
GVDD X 0.750
GVDD X 0.755
GVDD X 0.760
GVDD X 0.765
GVDD X 0.770
GVDD X 0.775
GVDD X 0.780
GVDD X 0.785
GVDD X0.790
VCM[5:0]
100000
100001
100010
100011
100100
100101
100110
100111
101000
101001
101010
101011
101100
101101
101110
101111
110000
110001
110010
110011
110100
110101
59
VCOMH
GVDD X 0.845
GVDD X 0.850
GVDD X0.855
GVDD X 0.860
GVDD X 0.865
GVDD X0.870
GVDD X0.875
GVDD X 0.880
GVDD X 0.885
GVDD X0.890
GVDD X 0.895
GVDD X 0.900
GVDD X0.905
GVDD X 0.910
GVDD X 0.915
GVDD X0.920
GVDD X 0.925
GVDD X 0.930
GVDD X 0.935
GVDD X 0.940
GVDD X 0.945
GVDD X 0.950
ST7781
010110
010111
011000
011001
011010
011011
011100
011101
011110
011111
GVDD X 0.795
GVDD X 0.800
GVDD X0.805
GVDD X0.810
GVDD X 0.815
GVDD X 0.820
GVDD X0.825
GVDD X 0.830
GVDD X 0.835
GVDD X0.840
110110
110111
111000
111001
111010
111011
111100
111101
111110
111111
GVDD X 0.955
GVDD X 0.960
GVDD X 0.965
GVDD X 0.970
GVDD X 0.975
GVDD X 0.980
GVDD X 0.985
GVDD X 0.990
GVDD X 0.995
GVDD X 1.000
11.1.20 Frame Rate and Color Control (R2Bh)
Frame Rate and Color Control (R2Bh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
FRS3
FRS2
FRS1
FRS0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
Default value
FRS[3:0] :Set the frame rate when the internal resistor is used for oscillator circuit.
Description
Ver. 1.7
FRS[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Frame Rate
27.5
29.3
33
36.7
40.3
44
47.7
51.3
55
64.2
73.3
82.5
91.7
100.8
110
114.1
60
ST7781
11.1.21 Gamma Control (R30h~R3Dh)
Gamma Control (R30h~R3Dh)
RS /WR /RD D15 D14 D13
D12
D11
D10
D9
D8
D7 D6 D5 D4
D3
D2
D1
D0
R30h
1
↑
1
Default value
R31h
1
↑
1
Default value
R32h
1
↑
1
Default value
R35h
1
↑
1
Default value
R36h
1
↑
1
Default value
R37h
1
↑
1
Default value
R38h
1
↑
1
Default value
R39h
1
↑
1
Default value
R3Ch
1
↑
1
Default value
R3Dh
1
↑
1
Default value
Description
Ver. 1.7
0
0
0
0
0
KP1[2]
KP1[1]
KP1[0]
0
0
0
0
0
KP0[2]
KP0[1]
KP0[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
KP3[2]
KP3[1]
KP3[0]
0
0
0
0
0
KP2[2]
KP2[1]
KP2[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
KP5[2]
KP5[1]
KP5[0]
0
0
0
0
0
KP4[2]
KP4[1]
KP4[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RP1[2]
RP1[1]
RP1[0]
0
0
0
0
0
RP0[2]
RP0[1]
RP0[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VRP0[3]
VRP0[2]
VRP0[1]
VRP0[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
KN1[2]
KN1[1]
KN1[0]
0
0
0
0
0
KN0[2]
KN0[1]
KN0[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
KN3[2]
KN3[1]
KN3[0]
0
0
0
0
0
KN2[2]
KN2[1]
KN2[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
KN5[2]
KN5[1]
KN5[0]
0
0
0
0
0
KN4[2]
KN4[1]
KN4[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RN1[2]
RN1[1]
RN1[0]
0
0
0
0
0
RN0[2]
RN0[1]
RN0[0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VRN0[3]
VRN0[2]
VRN0[1]
VRN0[0]
0
0
0
0
0
0
0
0
0
0
0
VRP1[4] VRP1[3] VRP1[2] VRP1[1] VRP1[0]
VRN1[4] VRN1[3] VRN1[2] VRN1[1] VRN1[0]
0
0
0
0
0
KP5-0[2:0]: γfine Adjustment Register for Positive Polarity.
RP1-0[2:0]: γgradient Adjustment Register for Positive Polarity.
VRP1 [4:0]: γamplitude Adjustment Register for Positive Polarity.
VRP0 [3:0]: γamplitude Adjustment Register for Positive Polarity.
KN5-0[2:0]: γfine Adjustment Register for Negative Polarity.
RN1-0[2:0]: γgradient Adjustment Register for Negative Polarity.
VRN1 [4:0]: γamplitude Adjustment Register for Negative Polarity.
VRN0 [3:0]: γamplitude Adjustment Register for Negative Polarity.
61
ST7781
11.1.22 Horizontal and Vertical RAM Address Position (R50h, R51h, R52h, R53h)
Horizontal and Vertical RAM Address Position(R50h,R51h,R52h,R53h)
RS /WR /RD D15 D14 D13 D12 D11 D10 D9
0
0
0
0
0
0
0
1
↑
1
0
0
0
0
0
0
0
Default value
0
0
0
0
0
0
0
R51h 1
↑
1
0
0
0
0
0
0
0
Default value
0
0
0
0
0
0
0
R52h 1
↑
1
0
0
0
0
0
0
0
Default value
0
0
0
0
0
0
0
R53h 1
↑
1
0
0
0
0
0
0
0
Default value
R50h
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
VSA8
HSA7
0
HEA7
HSA6
0
HEA6
HSA5
0
HEA5
HSA4
HSA3
HSA2
HSA1
HSA0
0
0
0
0
0
HEA4
HEA3
HEA2
HEA1
HEA0
1
1
1
0
1
1
1
1
VSA7
VSA6
VSA5
VSA4
VSA3
VSA2
VSA1
VSA0
0
0
0
0
0
0
0
0
0
VEA8
VEA7
VEA6
VEA5
VEA4
VEA3
VEA2
VEA1
VEA0
1
0
0
1
1
1
1
1
1
HSA [7:0], HEA [7:0] HSA[7:0] and HEA[7:0] are the start and end addresses of the window address area in
horizontal direction, respectively. HSA [7:0] and HEA [7:0] specify the horizontal range to write data. Set HSA [7:0]
and HEA [7:0] before starting RAM write operation. In setting, make sure that 8’h00 ≤ HAS < HEA ≤ 8’hEF
VSA [8:0], VEA [8:0] VSA [8:0] and VEA [8:0] are the start and end addresses of the window address area in
vertical direction, respectively. VSA [8:0] and VEA [8:0] specify the vertical range to write data. Set VSA [8:0] and
VEA [8:0] before starting RAM write operation. In setting, make sure that 9’h000 ≤ VSA < VEA ≤ 9’h13F.
Description
11.1.23 Gate Scan Control (R60h, R61h)
Gate Scan Control (R60h,R61h)
RS /WR /RD D15 D14
GS
0
1
↑
1
0
0
Default value
0
0
R61h 1
↑
1
0
0
Default value
R60h
D13
D12
D11
D10
D9
D8
D7
D6
NL5
0
0
0
NL4
0
0
0
NL3
0
0
0
NL2
0
0
0
NL1
0
0
0
NL0
0
0
0
0
0
0
0
0
0
0
0
D5
D4
D3
D2
D1
D0
SCN5 SCN4 SCN3 SCN2 SCN1 SCN0
0
0
0
0
0
0
0
0
0
NDL
0
REV
0
0
0
0
0
0
GS: Sets the direction of scan by the gate driver. Set GS bit in combination with SM and SS bits for the convenience
of the display module configuration and the display direction.
When GS=0, the scan direction is from G1 to G320
When GS=1, the scan direction is from G320 to G1
Description
Ver. 1.7
NL [5:0]: Sets the number of lines to drive the LCD at an interval of 8 lines. The DRAM address mapping is not
affected by the number of lines set by NL[5:0]. The number of lines must be the same or more than the number of
lines necessary for the size of the liquid crystal panel.
62
ST7781
NL[5:0]
6’h1D
6’h1E
6’h1F
6’h20
6’h21
6’h22
LCD Drive Line
240 lines
248 lines
256 lines
264 lines
272 lines
280 lines
NL[5:0]
6’h23
6’h24
6’h25
6’h26
6’h27
Others
LCD Drive Line
288 lines
296 lines
304 lines
312 lines
320 lines
Setting inhibited
SCN [5:0]: Specifies the gate line where the gate driver starts scan.
Scanning Start Position
SCN[5:0]
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
20h
21h
22h
23h
24h
25h
26h
27h
28h ~ 3Fh
SM=0
GS=0
G1
G9
G17
G25
G33
G41
G49
G57
G65
G73
G81
G89
G97
G105
G113
G121
G129
G137
G145
G153
G161
G169
G177
G185
G193
G201
G209
G217
G225
G233
G241
G249
G257
G265
G273
G281
G289
G297
G305
G313
Setting disabled
GS=1
G320
G312
G304
G296
G288
G280
G272
G264
G256
G248
G240
G232
G224
G216
G208
G200
G192
G184
G176
G168
G152
G152
G144
G136
G128
G120
G112
G104
G96
G88
G80
G72
G64
G56
G48
G40
G32
G24
G16
G8
Setting disabled
SM=1
GS=0
GS=1
G1
G320
G17
G304
G33
G288
G49
G272
G65
G265
G81
G240
G97
G224
G113
G208
G129
G192
G145
G176
G161
G160
G177
G144
G193
G128
G209
G112
G2
G96
G18
G80
G34
G64
G50
G48
G66
G32
G82
G16
G114
G303
G114
G303
G130
G287
G146
G271
G162
G255
G178
G239
G194
G223
G114
G207
G130
G191
G146
G175
G162
G159
G178
G143
G194
G127
G210
G111
G226
G95
G242
G79
G258
G63
G274
G47
G290
G31
G30
G15
Setting disabled
Setting disabled
NDL: Sets the source output level in non display area. NDL bit can keep the non-display area lit on.
NDL
0
1
Non- Display Area
Positive Polarity
Negative Polarity
V63
V0
V0
V63
REV: Enables the grayscale inversion of the image by setting REV = 1. This enables the ST7781 to display the same
image from the same set of data whether the liquid crystal panel is normally black or white. The source output
level during front, back porch periods and blank periods is determined by register setting (PTS).
Ver. 1.7
63
ST7781
REV
Non- Display Area
Positive Polarity
Negative Polarity
V63
V0
.
.
.
.
.
.
V0
V63
V0
V63
.
.
.
.
.
.
V63
V0
DRAM Data
18’h00000
.
.
.
18’h3FFFF
18’h00000
.
.
.
18’h3FFFF
0
1
11.1.24 Partial Image 1 Display Position (R80h)
Partial Image 1 Display Position (R80h)
RS
/WR
/RD
1
↑
1
D15 D14 D13 D12 D11 D10
Default value
D9
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
PTDP08 PTDP07 PTDP06 PTDP05 PTDP04 PTDP03 PTDP02 PTDP01 PTDP00
0
0
0
0
0
0
0
0
0
PTDP0 [8:0]: Sets the display start position of partial image 1. The display areas of the partial images 1 and 2 must
not overlap each another.
Description
11.1.25 Partial Image 1 Start/End Address (R81h, R82h)
Partial Image 1 Start/End Address(R81h,R82h)
RS
/WR /RD D15 D14 D13 D12 D11 D10 D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
R81h
1
↑
1
Default value
R82h
1
↑
1
Default value
Description
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PTSA08 PTSA07 PTSA06 PTSA05 PTSA04 PTSA03 PTSA02 PTSA01 PTSA00
0
0
0
0
0
0
0
0
0
PTEA08 PTEA07 PTEA06 PTEA05 PTEA04 PTEA03 PTEA02 PTEA01 PTEA00
0
0
0
0
0
0
0
0
0
PTSA0 [8:0] and PTEA0 [8:0]: Sets the start line and end line addresses of the RAM area, respectively for the partial
image
Note1: Make sure that PTSA0 ≤ PTEA0.
11.1.26 Partial Image 2 Display Position (R83h)
Partial Image 2 Display Position (R83h)
RS
/WR
/RD
1
↑
1
Default value
Description
Ver. 1.7
D15 D14 D13 D12 D11 D10
D9
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
PTDP18 PTDP17 PTDP16 PTDP15 PTDP14 PTDP13 PTDP12 PTDP11 PTDP10
0
0
0
0
0
PTDP1 [8:0]: Sets the display start position of partial image
Note1. The display areas of the partial images 1 and 2 must not overlap each another.
64
0
0
0
0
ST7781
11.1.27 Partial Image 2 Start / End Address (R84h, R85h)
Partial Image 2 Start/End Address(R84h,R85h)
RS
/WR
1
↑
/RD D15 D14 D13 D12 D11 D10 D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
R84h
1
Default value
R85h
1
↑
1
Default value
Description
Ver. 1.7
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PTSA18 PTSA17 PTSA16 PTSA15 PTSA14 PTSA13 PTSA12 PTSA11 PTSA10
0
0
0
PTEA18 PTEA17 PTEA1
0
0
0
0
0
0
0
0
PTEA15 PTEA14 PTEA13 PTEA12 PTEA11 PTEA10
0
0
0
0
0
PTSA1[8:0] and PTEA1[8:0]: Sets the start line and end line addresses of the DRAM area, respectively for the
partial image
Note1: Make sure that PTSA1 ≤ PTEA1.
65
0
0
ST7781
11.1.28 Panel Interface Control 1 (R90h)
Panel Interface Control 1 (R90h)
RS
/WR
/RD
1
↑
1
Default value
D15 D14 D13 D12 D11 D10
D9
D8
D7
0
0
0
0
0
0
DIVI1
DIVI0
0
0
0
0
0
0
0
0
0
0
D6
D5
D4
D3
D2
D1
D0
RTNI6 RTNI5 RTNI4 RTNI3 RTNI2 RTNI1 RTNI0
1
0
0
0
0
0
0
DIVI [1:0]: Sets the division ratio of the internal clock frequency. The ST7781’s internal operation is synchronized
with the frequency divided internal clock. When DIVI[1:0] setting is changed, the width of the reference
clock for liquid crystal panel control signals is changed. The frame frequency can be adjusted by register
setting (RTNI and DIVI bits). When changing the number of lines to drive the liquid crystal panel, adjust the
frame frequency too.
DIVI[1:0]
00
01
10
11
Division Ratio
1
2
4
8
Internal Operation Clock Frequency
Fosc/1
Fosc/2
Fosc/4
Fosc/8
RTNI [6:0]: Sets 1H (line) period. This setting is enabled while the ST7781’s display operation is synchronized with
internal clock.
Description
Ver. 1.7
RTNI[6:0]
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
Clocks/Line
0 clock
1 clock
2 clocks
3 clocks
4 clocks
5 clocks
6 clocks
7 clocks
8 clocks
9 clocks
10 clocks
11 clocks
12 clocks
13 clocks
14 clocks
15 clocks
16 clocks
17 clocks
18 clocks
19 clocks
20 clocks
21 clocks
22 clocks
23 clocks
24 clocks
25 clocks
26 clocks
27 clocks
28 clocks
29 clocks
30 clocks
31 clocks
RTNI[6:0]
20h
21h
22h
23h
24h
25h
26h
27h
28h
29h
2Ah
2Bh
2Ch
2Dh
2Eh
2Fh
30h
31h
32h
33h
34h
35h
36h
37h
38h
39h
3Ah
3Bh
3Ch
3Dh
3Eh
3Fh
Clocks/Line
32 clocks
33 clocks
34 clocks
35 clocks
36 clocks
37 clocks
38 clocks
39 clocks
40 clocks
41 clocks
42 clocks
43 clocks
44 clocks
45 clocks
46 clocks
47 clocks
48 clocks
49 clocks
50 clocks
51 clocks
52 clocks
53 clocks
54 clocks
55 clocks
56 clocks
57 clocks
58 clocks
59 clocks
60 clocks
61 clocks
62 clocks
63 clocks
66
RTNI[6:0]
40h
41h
42h
43h
44h
45h
46h
47h
48h
49h
4Ah
4Bh
4Ch
4Dh
4Eh
4Fh
50h
51h
52h
53h
54h
55h
56h
57h
58h
59h
5Ah
5Bh
5Ch
5Dh
5Eh
5Fh
Clocks/Line
64 clocks
65 clocks
66 clocks
67 clocks
68 clocks
69 clocks
70 clocks
71 clocks
72 clocks
73 clocks
74 clocks
75 clocks
76 clocks
77 clocks
78 clocks
79 clocks
80 clocks
81 clocks
82 clocks
83 clocks
84 clocks
85 clocks
86 clocks
87 clocks
88 clocks
89 clocks
90 clocks
91 clocks
92 clocks
93 clocks
94 clocks
95 clocks
RTNI[6:0]
60h
61h
62h
63h
64h
65h
66h
67h
68h
69h
6Ah
6Bh
6Ch
6Dh
6Eh
6Fh
70h
71h
72h
73h
74h
75h
76h
77h
78h
79h
7Ah
7Bh
7Ch
7Dh
7Eh
7Fh
Clocks/Line
96 clocks
97 clocks
98 clocks
99 clocks
100 clocks
101 clocks
102 clocks
103 clocks
104 clocks
105 clocks
106 clocks
107 clocks
108 clocks
109 clocks
110 clocks
111 clocks
112 clocks
113 clocks
114 clocks
115 clocks
116 clocks
117 clocks
118 clocks
119 clocks
120 clocks
121 clocks
122 clocks
123 clocks
124 clocks
125 clocks
126 clocks
127 clocks
ST7781
11.1.29 Panel Interface Control 2 (R92h)
Panel Interface Control 2 (R92h)
RS
/WR
/RD
1
↑
1
Default value
D15 D14 D13 D12 D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
NOWI2
NOWI1
NOWI0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
NOWI [2:0]: Sets the non-overlap period of adjacent gate outputs. The setting is enabled in display operation
synchronizing with the internal clock.
Description
NOWI[2:0]
Gate Non-Overlap Period
000
0 clocks
001
1 clocks
010
2 clocks
011
3 clocks
100
4 clocks
101
5 clocks
110
6 clocks
111
7 clocks
Note: The gate output non-overlap period is defined by the number of frequency-divided internal clocks, the
frequency of which is determined by instruction (DIVI), from the reference point.
11.1.30 EEPROM ID Code (RD2h)
EEPROM ID Code (RD2h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
ID6
ID5
ID4
ID3
ID2
ID1
ID0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
Description
ID [6:0]: ST7781 supply 7bit ID code for LCD module version ID
11.1.31 EEPROM Control Status (RD9h)
EEPROM Control Status (RD9h)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
D6
D5
ID_EN VCM_EN
0
0
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
0
0
ID_EN: ”1” = Command EEPROM ID Code (RD2h) Enable.
”0” = Command EEPROM ID Code (RD2h) Disable.
VCM_EN: ”1” = Command EEPROM VCOM Offset Control (RFEh) Enable.
”0” = Command EEPROM VCOM Offset Control (RFEh) Disable.
Description
11.1.32 EEPROM Read Command (RDEh)
EEPROM Read Command (RDEh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
1
0
1
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
Description
Ver. 1.7
EEPROM Read Command.
67
ST7781
11.1.33 EEPROM Wite Command (RDFh)
EEPROM Write Command (RDFh)
/RD D15 D14 D13 D12 D11 D10 D9 D8
D7
D6
D5
D4
D3
D2
D1
D0
EE_IB7
EE_IB6
EE_IB5
EE_IB4
EE_IB3
EE_IB2
EE_IB1
EE_IB0
RS
/WR
1
↑
1
0
0
0
0
0
0
0
0
1
↑
1
0
0
0
0
0
0
0
0 EE_CMD7 EE_CMD6 EE_CMD5 EE_CMD4 EE_CMD3 EE_CMD2 EE_CMD1 EE_CMD0
1
↑
1
0
0
0
0
0
0
0
0
1
0
1
0
0
1
0
1
EE_IB[7:0]: Write Operation Selection.
EE_IB[7:0]=D2h,Write ID Code
EE_IB[7:0]=FEh,Write VCOM Offest
EE_CMD[7:0]: Select to Program/Erase ; Program Command : 3Ah ; Erase Command : C5h
Description
11.1.34 EEPROM Enable (RFAh)
EEPROM Enable (RFAh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
MTPPROG
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
Description
MTPPROG:”1” for enable EEPROM function with SW_EE =1
11.1.35 EEPROM VCOM Offset (RFEh)
EEPROM VCOM Offset (RFEh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
VCMF[4:0]: Set VCOMH Voltage level for reduce the flicker issue
VCMF[4:0]
Description
Ver. 1.7
VCOMH Output Level
00000
“VCOMH”
00001
“VCOMH”+1d
00010
“VCOMH”+2d
|
|
01110
“VCOMH”+14d
01111
“VCOMH”+15d
10000
“VCOMH”-16d
10001
“VCOMH”-15d
10010
“VCOMH”-14d
|
|
11110
“VCOMH”-2d
11111
“VCOMH”-1d
Note: 1d=GVDDX0.005, 2d= GVDDX0.01, 3d = GVDDX0.015....
3V <= VCOMH + nd <=5V (n= -16~15)
68
D4
D3
D2
D1
D0
VCMF4 VCMF3 VCMF2 VCMF1 VCMF0
0
0
0
0
0
ST7781
11.1.36 FAh/FEh Enable (RFFh)
FAh/FEh Enable Enable (RFFh)
RS
/WR
/RD
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
↑
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
FXEN
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Default value
Description
Ver. 1.7
FXEN:”1” for enable FAh and FEh function.
69
ST7781
12. Reset Function
The ST7781 is initialized by the RESET input. During reset period, the ST7781 is in a busy state and instruction from the
MCU and DRAM access are not accepted. The ST7781’s internal power supply circuit unit is initialized also by the RESET
input. The RESET period must be secured for at least 1ms. In case of power-on reset, wait until the RC oscillation
frequency stabilizes (for 1 ms). During this period, DRAM access and initial instruction setting are prohibited.
12.1. Initial State of Instruction Bits (Default)
See the Instruction desscription.The default value is shown in the parenthesis of each instruction bit cell.
12.2. RAM Data Initialization
The RAM data is not automatically initialized by the RESET input. It must be initialized by software in display-off
period.
12.3. Note on Reset Function
(1) When a RESET input is entered into the ST7781 while it is in deep standby mode, the ST7781 starts up the inside
logic regulator and makes a transition to the initial state. During this period, the state of the interface pins may
become unstable. For this reason, do not enter a RESET input in deep standby mode.
(2) When transferring instruction in either two or three transfers via 8-/9-/16-bit interface, make sure to execute data
transfer synchronization after reset operation.
12.4 Reset Timing Characterics
Fig. 12.4 Reset timing
Signal
RESET
Ver. 1.7
Symbol
TRESL
TREST
VDDI=1.65 to 3.3V, VDD=2.5 to 3.3V, AGND=DGND=0V, Ta=25℃
Parameter
Min
Max
Unit
Description
1
Reset Low Level Width
ms
1
Reset Complete Time
ms
Table 12.4.1: Reset timing Characteristics
70
ST7781
13. FMARK Function
The ST7781 outputs an FMARK pulse when the ST7781 is driving the line specified by FMP[8:0] bits. The FMARK signal
can be used as a trigger signal to write display data in synchronization with display operation by detecting the address
where data is read out for display operation.
The FMARK output interval is set by FMI[2:0] bits. Set FMI[2:0] bits in accordance with display datarewrite cycle and data
transfer rate. Set FMARKOE = 1 when outputting FMARK pulse from the FMARK pin.
FMI[2:0]
000
001
011
101
Others
FMP[8:0]
9’h000
9’h001
9’h002
9’h003
Output Interval
1 Frame
2 Frame
4 Frame
6 Frame
Setting Prohibited
.
.
.
Table 13.1: FMARK Interval
9’h174
9’h175
9’h176
9’h177
FMARK Output Position
0 th line
1 st line
2 nd line
3 rd line
.
.
.
372 th line
373 th line
374 th line
375 th line
Table 13.2: FMARK Output Position
13.1 FMP Setting Example
Fig. 13.1.1 FMARK Setting Example
Ver. 1.7
71
ST7781
13.2 Display Operation Synchronous Data Transfer using FMARK
The ST7781 uses FMARK signal as a trigger signal to start writing data to the internal DRAM in synchronization with
display scan operation.
Fig. 13.2.1 Display Synchronous Data Transfer Interface
In this operation, moving picture display is enabled via system interface by writing data at higher than the internal display
operation frequency to a certain degree, which guarantees rewriting the moving picture DRAM area without causing flicker
on the display. The data is written in the internal RAM in order to transfer only the data written over the moving picture
display area and minimize the data transfer required for moving picture display.
Fig. 13.2.2 Moving Picture Data Transfers via FMARK Function
When transferring data in synchronization with FMARK signal, minimum DRAM data write speed and internal clock
frequency must be taken into consideration. They must be more than the values calculated from the following equations.
Internal clock frequency
( fosc )[Hz ]
= Frame Frequency (min .)[Hz ]× (DisplayPor ch ( NL ) + FrontPorch (FP ) + BackPorch (BP )) × 16 (clocks ) × var iance
RAMWriteSp eed (min .)[Hz ] >
240 × DisplayLin es ( NL )
(FrontPorch (FP ) + BackPorch (BP ) + DisplayLin
es (NL ) − m arg ins ) × 16 (clocks ) ×
1
fosc
Note: When RAM write operation is not started immediately following the rising edge of FMARK, the time from the rising
edge of FMARK until the start of RAM write operation must also be taken into account.
Examples of DRAM writes speed and the frequency of the internal clocks are as follows.
Example:
Ver. 1.7
Display size
320 RGB x 240 lines,
Total number of lines (NL)
320 lines
Back/Front porch:
14/2 lines
Frame frequency
60 Hz
72
ST7781
Internal Clock Frequency (fosc) [Hz] = 60Hz x (320+2+14) x 16 clocks x 1.1/0.9 = 394 kHz
Note1. When setting the internal clock frequency, possible causes of fluctuation must also be taken into consideration. In
this example, the internal clock frequency allows for a margin of ±10% for variances and guarantee that display
operation is completed within one FMARK cycle.
Note2. This example includes variances attributed to LSI fabrication process and room temperature. Other possible causes
of variances, such as differences in external resistors and voltage change are not considered in this example. It is
necessary to include a margin for these factors.
Minimum Speed for DRAM Writing [Hz] > 240x320 / {((14+320-2)lines x 16 clocks) / 394kHz} = 5.7MHz
Note1. In this example, it is assumed that the ST7781 starts writing data in the internal DRAM on the rising edge of
FMARK.
Note2. There must be at least a margin of 2 lines between the line to which the ST7781 has just written data and the line
where display operation on the LCD is performed.
Note3. The FMARK signal output position is set to the line specified by FMP[8:0] bits.
Line Processing
In this example, DRAM write operation at a speed of 5.67MHz or more, when starting on the rising edge of FMARK,
guarantees the completion of data write operation in a certain line address before the ST7781 starts the display operation
of the data written in that line and can write moving picture data without causing flicker on the display.
Fig. 13.2.3 Write/Display Operation Timing
Ver. 1.7
73
ST7781
14. 8 - Color Display Mode
The ST7781 has a function to display in 8 colors. In this display mode, only V0 and V63 are used and power supplies to
other grayscales are turned off to reduce power consumption. In 8-color display mode, the γ-adjustment registers
KP5-0[2:0], RP1-0[2:0], VRP0 [3:0], KN5-0[2:0], RN1-0[2:0], VRN1 [4:0], VRN0 [3:0], are disabled and the power supplies
to V1 to V62 are halted. The ST7781 does not require DRAM data rewrite for 8-color display by writing the MSB to the rest
in each dot data to display in 8 colors.
Fig. 14.1 8-Color Display Mode
Ver. 1.7
74
ST7781
15. Window Address Function
The window address function enables writing display data consecutively in a rectangular area (a window address area)
made on the internal DRAM. The window address area is made by setting the horizontal address register (star: HAS[7:0],
end HEA[7:0] bits) and the vertical address register(start: VSA[8:0], end: VEA[8:0] bits) The AM bits sets the transition
direction of RAM address(either increment or decrement). These bits enable the ST7781 to write data including image data
consecutively not taking data wrap positions into account.
The window address area must be made within the GRAN address map area. Also, DRAM address bits (RAM address set
register) must be an address within the window address area.
[Window address setting area]
(Horizontal direction) 00H ≦ HSA[7:0] ≦ HEA[7:0] ≦ ”EF”H
(Vertical direction) 00H ≦VSA[8:0] ≦ VEA[8:0] ≦ ”13F”H
[RAM address, AD (an address within a window address area)]
(RAM address) HSA[7:0] ≦AD[7:0] ≦HEA[7:0]
VSA[8:0] ≦AD[15:8] ≦VEA[8:0]
DRAM Address Map
0"0000"h
0"00EF”h
Window Address Area
2010h
203Fh
2110h
213Fh
4F10h
4F3Fh
I”3F00"h
I"3FEF"h
Window address setting area
HSA[7 :0 ] = 1 0 h , HSA[7 :0 ] = 3 Fh , I/D = 1 (increment)
VSA[8 :0 ] = 2 0 h , VSA[8 :0 ] = 4 Fh , AM = 0 (horizontal writing )
Fig.15.1 DRAM Access Window Map
Ver. 1.7
75
ST7781
16. Gamma Correction
ST7781 incorporate the γ- correction function to display 262,244 colors for the LCD panel. Theγ-correction is performed
with 3 groups of registers determining eight reference grayscale levels, which are gradient adjustment, amplitude
adjustment and fine- adjustment registers for positive and negative polarities, to make ST7781 available with liquid crystal
panels of various characteristics.
Fig.16.1 Grayscale Voltage Generation
Ver. 1.7
76
ST7781
GVDD
VR0P0
0~30R
5R
1uF/10V
VgP0
VRPO[3:0]
RP0
PKP0[2:0]
VP1
RP1 VP2
4R
RP2
VP3
RP3
VP4
RP4
RP5
VP6
RP6
VP7
RP7
VRCP0
0~28R
8 to 1
Selection
VP5
VgP1
VP8
PRPO[2:0]
VP9
PKP1[2:0]
RP8 VP10
RP9
VP11
RP10 VP12
1R
RP11 VP13
RP12 VP14
8 to 1
Selection
VgP8
RP13 VP15
RP14 VP16
RP15
PKP2[2:0]
VP17
RP16 VP18
RP17 VP19
RP18 VP20
1R
RP19 VP 21
8 to 1
Selection
VgP20
RP20 VP22
RP21 VP23
RP22
RP23
RP24
VP24
PKP3[2:0]
VP25
VP26
RP25 VP27
RP26 VP28
1R
RP27 VP29
8 to 1
Selection
VgP43
RP28 VP30
RP29 VP31
RP30 VP32
PKP4[2:0]
RP31
VP33
RP32
VP34
RP33 VP35
RP34 VP36
1R
RP35 VP37
8 to 1
Selection
VgP55
RP36 VP38
RP37 VP39
RP38 VP40
VRCP1
0~28R
VP41
RP39
PRP1[2:0]
VP42
RP40 VP43
RP41 VP44
4R
PKP5[2:0]
RP42 VP45
8 to 1
Selection
VgP62
RP43 VP46
RP44 VP47
RP45 VP48
RP46
VP49
VR0P1
0~31R
8R
VRP1[4:0]
RP47
Fig.16.2 Grayscale Voltage Adjustment
Ver. 1.7
77
VgP63
ST7781
1. Gradient Adjustment Registers
The gradient adjustment registers are used to adjust the gradient of the curve representing the relationship between the
grayscale and the grayscale reference voltage level. To adjust the gradient, the resistance values of variable resistors in the
middle oh the ladder resistor are adjusted by registers PRP0[2:0]/PRN0[2:0], PRP1[2:0]/PRN1[2:0]. The registers consist
of positive and negative polarity registers, allowing asymmetric drive.
2. Amplitude Adjustment Registers
The amplitude adjustment registers, VRP0[3:0]/VRN0[3:0], VRP1[4:0], are used to adjust the amplitude of grayscale
voltages. To adjust the amplitude, the resistance values of variable resistors at the top and the bottom of the ladder resister
are adjusted.
Grayscale Voltage
Grayscale Voltage
Grayscale Voltage
3. Fine Adjustment Registers
The fine adjustment registers are used to fine-adjust grayscale voltage levels. To fine-adjust grayscale voltage levels, fine
adjustment registers adjust the reference voltage level, 8 levels for each register generated from the ladder resistor, in
respective 8-to-1 selectors. Same with other registers, the fine adjustment registers consist of positive and negative polarity
registers.
Fig.16.3 Gamma curve adjustment
Register Groups
Gradient Adjustment
Amplitude
Adjustment
Fine Adjustment
Positive Polarity
PRP0[2:0]
PRP1[2:0]
VRP0[3:0]
VRP1[4:0]
KP0[2:0]
KP1[2:0]
KP2[2:0]
KP3[2:0]
KP4[2:0]
KP5[2:0]
Negative Polarity
PRN0[2:0]
PRN1[2:0]
VRN0[3:0]
VRN1[4:0]
KN0[2:0]
KN1[2:0]
KN2[2:0]
KN3[2:0]
KN4[2:0]
KN5[2:0]
Description
Variable Resistor VRCP0,VRCN0
Variable Resistor VRCP1,VRCN1
Variable Resistor VROP0,VRON0
Variable Resistor VROP1,VRON1
8-to-1 Selector (Voltage Level of Grayscale1)
8-to-1 Selector (Voltage Level of Grayscale8)
8-to-1 Selector (Voltage Level of Grayscale20)
8-to-1 Selector (Voltage Level of Grayscale43)
8-to-1 Selector (Voltage Level of Grayscale55)
8-to-1 Selector (Voltage Level of Grayscale62)
Table 16.4: Register Description
Ver. 1.7
78
ST7781
Ladder Resistors and 8-to-1 Selector Block Configuration
The reference voltage generation block consists of two ladder resistor units including variable resistors and 8-to-1 selectors.
Each 8-10-1 selector selects one of the 8 voltage levels generated from the ladder resistor unit to output as a grayscale
reference voltage. Both variable resistors and 8-to-1 selectors are controlled according to theγ-correction registers. This
unit has pins to connect a volume resistor externally to compensate differences in various characteristic of panels.
Variable Resistors
ST7781 uses variable resistors of the following three purposes: gradient adjustment (VRCP(N)0/VRCP(N)1);amplitude
adjustment (1) (VROP(N)0); and the amplitude adjustment (2) (VROP(N)1). The resistance values of these variable
resistors are set by gradient adjustment registers and amplitude adjustment registers as follows.
Gradient Adjustment
PRP(N)0/1[2:0]
VRCP(N)0
Register
Resistance
000
0R
001
4R
010
8R
011
12R
100
16R
101
20R
110
24R
111
28R
Amplitude Adjustment (1)
VRP(N)0[3:0]
VROP(N)0
Register
Resistance
0000
0R
0001
2R
0010
4R
:
:
:
:
1101
26R
1111
28R
1111
30R
Amplitude Adjustment (2)
VRP(N)1[4:0]
VROP(N)1
Register
Resistance
00000
0R
00001
1R
00010
2R
:
:
:
:
11101
29R
11110
30R
11111
31R
Table 16.5: Resistance Adjustment
8-to-1 selectors
The 8-to-1 selector selects one of eight voltage levels generated from the ladder resistor unit according to the fine
adjustment register and output the selected voltage level as a reference grayscale voltage (VgP(N)1~6). The table below
shows the setting in the fine adjustment register and the selected voltage levels for respective reference grayscale
voltages.
Register
KP(N)[2:0]
000
001
010
011
100
101
110
111
Fine Adjustment Registers and Selected Voltage
Selected Voltage
VgP(N)1
VgP(N)8
VgP(N)20
VgP(N)43
VgP(N)55
VP(N)1
VP(N)9
VP(N)17
VP(N)25
VP(N)33
VP(N)2
VP(N)10
VP(N)18
VP(N)26
VP(N)34
VP(N)3
VP(N)11
VP(N)19
VP(N)27
VP(N)35
VP(N)4
VP(N)12
VP(N)20
VP(N)28
VP(N)36
VP(N)5
VP(N)13
VP(N)21
VP(N)29
VP(N)37
VP(N)6
VP(N)14
VP(N)22
VP(N)30
VP(N)38
VP(N)7
VP(N)15
VP(N)23
VP(N)31
VP(N)39
VP(N)8
VP(N)16
VP(N)24
VP(N)32
VP(N)40
Table 16.7: Fine Adjustment Registers and Selected Voltage
Ver. 1.7
79
VgP(N)62
VP(N)41
VP(N)42
VP(N)43
VP(N)44
VP(N)45
VP(N)46
VP(N)47
VP(N)48
ST7781
Source Output Levels
Fig.16.8 Relationship between Source Output and VCOM
Fig.16.9 Relationship between DRAM Data and Output Level
Ver. 1.7
80
ST7781
17. Application
17.1. Configuration of Power Supply Circuit
Fig.17.1 Power Supply Circuit Block
Ver. 1.7
81
ST7781
The following table shows specifications of external elements connected to the ST7781 power supply circuit.
Items
Recommended Specification
Pin Connection
GVDD, VCI1, VCC, VCL, VCOMH,
VCOML, C11P/N, C12P/N, C21P/N, AVDD
6.3 V
1 µF Capacity
10 V
Schottky Diode
C22P/N ,C23P/N
25 V
VF<0.4V/20mA at 25°C, VR ≥30V
VGH, VGL
(GND – VGL),
Table 17.1.1: Outside Compoments
17.2. Standby Mode
Into Standby flow
Exit Standby flow
Display Off
Power Supply
Setting
Set STB
(STB=1)
Set STB
(STB=0)
Into Standby mode
Display On
Normal mode
Fig.17.2 Standby Mode Register Setting Sequence
Ver. 1.7
82
ST7781
17.3. Power Supply Configuration
When supplying and cutting off power, follow the sequence below. The setting time for oscillators, circuits and operational
amplifiers depends on external resistance and capacitance.
Power Supply on Sequence
VDD
VDDI
Normal Display
VSS
VDD
VDDI
or
VDDI,VDD Simultaneously
Display Off
DTE=0
D[1:0]=00
GON=1
BASEE=0
Reset Signal Initial IC
Into Standby Mode
STB=1
Display Control Setting
Power Control
Registers Initial
LCD Power Supply Halt
Setting
SAP=0
AP[2:0]=000
PON=0
Set Display Windows
Power Supply Off Sequence
Power Supply Startup
1 Setting
VDDI VDD
Frame Rate Setting
VSS
VDD
or
VDDI,VDD Simultaneously
VDDI
Power Supply Startup
2 Setting
Gamma Cluster
Setting
Display On
Normal Display
Fig.17.3 Power Supply ON/OFF Sequence
Ver. 1.7
83
ST7781
17.4. Voltage Generation
The pattern diagram for setting the voltages and the waveforms of the voltages of the ST7781 are as follows.
BT[2:0]
AVDD
VGH (10~16.5)V
VCI1
VRH[3:0]
AVDD
GVDD(3~(AVDD-0.5))V
GVDD
VCOM[5:0]
VDDI
AVDD (4.5~5.6)V
VCOMH(3~(AVDD-0.5))V
VDV [4:0]
VDD
VCOML((VCL+0.5)~0.0)V
VCI1
VCL
BT[2:0]
VCL=-VCI1
VGL(-14~-5)V
Fig.17.4 Voltage Configuration Diagram
Note1: The AVDD, VGH, VGL, and VCL output voltage levels are lower than their theoretical levels (ideal voltage levels)
due to current consumption at respective outputs. The voltage levels in the following relationships (AVDD – GVDD )
>0.5V, (VCOML – VCL) > 0.5V, are the actual voltage levels. When the alternating cycles of VCOM are set high (e.g.
the polarity inverts every line cycle), current consumption is large. In this case, check the voltage before use.
Note 2: In operation, setting voltages within the respective voltage ranges are recommended.
17.5. Applied Voltage to the TFT panel
Fig.17.5 Voltage Output to TFT LCD Panel
Ver. 1.7
84
ST7781
17.6. Partial Display Function
The ST7781 allows selectively driving two partial images on the screen at arbitrary positions set in the screen
drive position registers.The following example shows the setting for partial display function:
BASEE
NL[5:0]
PTDE0
PTSA0[8:0]
PTEA0[8:0]
PTDP0[8:0]
PTDE1
PTSA1[8:0]
PTEA1[8:0]
PTDP1[8:0]
Base Image Display Setting
0
6’h27
Partial Image 1 Display Setting
1
9’h000
9’h00F
9’h080
Partial Image 2 Display Setting
1
9’h020
9’h02F
9’h0C0
Table 17.6.1: Partial Setting Example
Fig.17.6 Partial Display Example
Ver. 1.7
85
ST7781
17.7. Resizing Function
ST7781 supports resizing function (x1/2, x1/4), which is performed when writing image data to DRAM. The resizing
function is enabled by setting a window address area and the RSZ bit which represents the resizing factor (x1/2, x1/4) of
image. The resizing function allows the system to transfer the original-size image data into the DRAM with resized image
data.
160
320
Fig.17.8 Data Transfer in Resizing Mode
Fig.17.8.1 Resizing Example
Original Image Size (X × Y)
640 × 480
352 × 288
320 × 240
176 × 144
120 × 160
132 × 132
Resized Image Resolution
1/2 (RSZ=2’h1)
1/4 (RSZ=2’h3)
320 × 240
160 × 120
176 × 144
88 × 72
60 × 120
80× 60
88 × 72
44× 36
60× 80
30 × 40
66 × 66
33 × 33
Table 17.8.1: Resized Image Resolution
The RSZ bit sets the resizing factor of an image. When setting a window address area in the internal DRAM, the DRAM
window address area must fit the size of resized image. The following examples show the resizing setting.
Ver. 1.7
86
ST7781
Original image data number in horizontal direction
Original image data number in Vertical direction
Resizing Ration
Resizing Setting
Remainder pixels in horizontal direction
Remainder pixels in vertical direction
DRAM writing start address
DRAM window setting
Table 17.8.2: Resized Coefficient
Ver. 1.7
87
RSZ
RCH
RCV
AD
HAS
HEA
VSA
VEA
X
Y
1/N
N-1
H
V
(X0, Y0)
X0
X0+dX-1
Y0
Y0+dY-1
ST7781
18. Revise History
ST7781 Serial Specification Revision History
Version
Date
Description
1.0
2009/02/10 Release Version
1.1
2009/03/16
1.2
2009/03/30 Application Flow (Page80)
TESTI PIN Name Modify (Page4)
Recommended Specification (Page79)
Pad Arrangement (Page2)
Pad Center Coordinates(Page4)
1.3
2009/04/16 Add DRAM Address Map Table(Page39)
Configuration of Power Supply Circuit(Page79)
Recommended Specification (Page80)
1.4
2009/04/29 Modify Power Consumption Table(Page 24)
Modfity Pad Center Coordinates (Page2 )
1.5
2009/04/30 Modifty Pad Pump Specification (Page3 )
Configuration of Power Supply Circuit (Page79)
1.7
Ver. 1.7
2009/08/27 Add SPI interface related Description (Page 1,2,4,22,40,41,80)
88