Table detection

[fl4p]

table2matrix

Datasheets contain merged cells if a unit or condition applies to multiple rows. headers might also be merged. when iterating the data row wise, we need to first resolve the merged cells and copy the value across all rows within the span.

• resolve row-span and col-span

  +-----------+---+---+---+
  | A         | B | C | D |
  |           +---+---+---+
  |           | E         |
  |           +---+---+---+
  |           | E | C | C |
  +---+---+---+---+---+---+
  | E | C | C | C | C | C |
  +---+---+---+---+---+---+

              V

[['A', 'A', 'A', 'B', 'C', 'D'],
 ['A', 'A', 'A', 'E', 'E', 'E'],
 ['A', 'A', 'A', 'E', 'C', 'C'],
 ['E', 'C', 'C', 'C', 'C', 'C']]

Tabula

• the web version has an auto-detect function, which performs much better than tabula-java (CLI)
• it does not auto-detect nested tables
• selecting the whole page leads to poor results

EPC2306

Stream

(FIELD* headers are actually empty, the CSV->MD converter put them)

Table

FIELD1	FIELD2	Dynamic Characteristics# (TJ = 25°C unless otherwise stated)	FIELD4	FIELD5	FIELD6	FIELD7
	PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNIT
CISS	Input Capacitance			1777	2369
CRSS	Reverse Transfer Capacitance	VDS = 50 V, VGS = 0 V		5.8
COSS	Output Capacitance			616	803	pF
COSS(ER)	Effective Output Capacitance, Energy Related (Note 1)			730
VDS = 0 to 50 V, VGS = 0 VCOSS(TR)	Effective Output Capacitance, Time Related (Note 2)			882
RG	Gate Resistance			0.4		Ω
QG	Total Gate Charge	VDS = 50 V, VGS = 5 V, ID = 25 A		12.3	16.2
QGS	Gate to Source Charge			4.3
QGD	Gate-to-Drain Charge	VDS = 50 V, ID = 25 A		1.1
						nC
QG(TH)	Gate Charge at Threshold			3.1
QOSS	Output Charge	VDS = 50 V, VGS = 0 V		44	57
QRR	Source-Drain Recovery Charge			0

Latice

• headers (min) are off

Table

Dynamic Characteristics# (TJ	25°C unless otherwise stated)	FIELD3	FIELD4	FIELD5	FIELD6	FIELD7
PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNIT
CISS	Input Capacitance	VDS = 50 V, VGS = 0 V		1777	2369	pF
CRSS	Reverse Transfer Capacitance		5.8
COSS	Output Capacitance		616	803
COSS(ER)	Effective Output Capacitance, Energy Related (Note 1)	VDS = 0 to 50 V, VGS = 0 V		730
COSS(TR)	Effective Output Capacitance, Time Related (Note 2)		882
RG	Gate Resistance			0.4		Ω
QG	Total Gate Charge	VDS = 50 V, VGS = 5 V, ID = 25 A		12.3	16.2	nC
QGS	Gate to Source Charge	VDS = 50 V, ID = 25 A		4.3
QGD	Gate-to-Drain Charge		1.1
QG(TH)	Gate Charge at Threshold		3.1
QOSS	Output Charge	VDS = 50 V, VGS = 0 V		44	57
QRR	Source-Drain Recovery Charge			0

Findings

• stream extraction method appears to be more usable here
• it doesn't provide an output that supports merged cells?
• the JSON output contains raw cell coordinates. cells are already grouped in rows. a cell with a rowspan (merged vertically) occurs in the first row. all subsequent rows within the span (and the same column) will have empty content. we can easily fill these rows with the same value
• auto-detect does not find nested tables and output quality suffers when selecting the whole page
• when we know the table bbox, the output can be good

BSB028N06NN3GXUMA2.pdf

tabula stream

Parameter	Symbol	Conditions		Values		Unit
			min.	typ.	max.
Dynamic characteristics
Input capacitance	C iss		-	8800	12000	pF
		V GS=0 V, V DS=30 V,
Output capacitance	C oss		-	2100	2800
		f =1 MHz
Reverse transfer capacitance	Crss		-	64	-
Turn-on delay time	t d(on)		-	21	-	ns
Rise time	t r	V DD=30 V, V GS=10 V,	-	9	-
		I =30 A, R
Turn-off delay time	t d(off)	D G,ext=1.6 W	-	38	-
Fall time	t f		-	6	-

• results are good. it even uses the column headers from the "previous" table (min/typ/max)

pix2image

• for the first 3 rows it detects a single rowspan=3 , across all columns. this could be simplified. still it its not a usable result.

[fl4p]

pix2text

p2t predict -l en --resized-shape 2048 --file-type pdf -i datasheets/epc/EPC2306.pdf -o epc2306.md \
    --save-debug-res output-debug-p2t 

• it supports merged cells
• it appears to ignore lines mostly and put a new table grid from text boundaries

MD table (no merged cells)

	PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNIT
CIss	Input Capacitance	Vos=50V,Vcs=0V		1777	2369	pF
Cass	Reverse Transfer Capacitance		5.8
Coss	Output Capacitance			616	803
CoSSER	Effective Output Capacitance, Energy Related (Note 1)	Vos=0to 50V,VGs=0V		730
CossTR	Effective Output Capacitance, Time Related (Note 2)		882
Re	Gate Resistance			0.4		Q
QG	Total Gate Charge	Vps=50V,Vcs=5V,lb=25A		12.3	16.2	nC
QGs	Gate to Source Charge	Vps=50V,lp=25 A		4.3
QG	Gate-to-Drain Charge		1.1
QGirn)	Gate Charge at Threshold		3.1
Qoss	Output Charge	Vps=50V,Vcs=0V		44	57
QRR	Source-Drain Recovery Charge			0

HTML

p2t = Pix2Text.from_config()
doc = p2t.recognize_pdf('../datasheets/EPC/EPC2306.pdf', page_numbers=[1], resized_shape=2048)
table = doc.pages[0].elements[9]
print(table.meta['html'][0])

	PARAMETER	TEST CONDITIONS	MIN	TYP	MAX	UNIT
CIss	Input Capacitance	Vos=50V,Vcs=0V		1777	2369	pF
Cass	Reverse Transfer Capacitance			5.8
Coss	Output Capacitance			616	803
CoSSER	Effective Output Capacitance, Energy Related (Note 1)	Vos=0to 50V,VGs=0V		730
CossTR	Effective Output Capacitance, Time Related (Note 2)			882
Re	Gate Resistance			0.4		Q
QG	Total Gate Charge	Vps=50V,Vcs=5V,lb=25A		12.3	16.2	nC
QGs	Gate to Source Charge	Vps=50V,lp=25 A		4.3
QG	Gate-to-Drain Charge			1.1
QGirn)	Gate Charge at Threshold			3.1
Qoss	Output Charge	Vps=50V,Vcs=0V		44	57
QRR	Source-Drain Recovery Charge			0

Another example

HTML and MD tables

Parameter	symbol	Values			Unte	Note I Test Condition
		Min.	Typ.	Max.
Drain-source breakdown voltage	V(BR)DSS	100	-	-	V	Ves=0V, Io=1 mA
Gate threshold voltage	Vesth	2.2	3.0	3.8	V	Vos=Ves, /D=72 uA
Zero gate voltage drain current	ls	:	0.1 10	1 100	uA	Vos=100V, Ves=0 V, T=25°0 Vps=100 V, Ves=0 V, Tj=125°0
Gate-source leakage current	less	-	10	100	nA	Ves=20 V,Vos=0\V
Drain-source on-state resistance	Rosom	:	4.3 5.3	5.0 7.1	m2	Ves=10 V,D=50A Ves=6V,D=25 A
Gate resistance)	Re	-	1.2	1.8	Q	-
Transconductance	Ofs	50	100	-	S	|Vos|>2|/p|Ros(on)max,|b=50 A

Parameter	symbol	Values	Unte	Note I Test Condition	Min.	Typ.	Max.
Drain-source breakdown voltage	V(BR)DSS	100	-	-	V	Ves=0V, Io=1 mA
Gate threshold voltage	Vesth	2.2	3.0	3.8	V	Vos=Ves, /D=72 uA
Zero gate voltage drain current	ls	:	0.1 10	1 100	uA	Vos=100V, Ves=0 V, T=25°0 Vps=100 V, Ves=0 V, Tj=125°0
Gate-source leakage current	less	-	10	100	nA	Ves=20 V,Vos=0\V
Drain-source on-state resistance	Rosom	:	4.3 5.3	5.0 7.1	m2	Ves=10 V,D=50A Ves=6V,D=25 A
Gate resistance)	Re	-	1.2	1.8	Q	-
Transconductance	Ofs	50	100	-	S		Vos

[fl4p]

img2table

• looks promising
• pure OCR solution