sx150x_89b-datasheet

ADVANCED COMMUNICATIONS & SENSING
Rev 4 – 26
th
April 2011 30 www.semtech.com
SX1508B/SX1509B
World’s Lowest Voltage Level Shifting GPIO
with LED Driver and Keypad Engine
0x21
RegLEDDriverEnableA
0x00 7:0
Enables LED Driver for each [output-configured] IO
0 : LED Driver is disabled
1 : LED Driver is enabled
7:3 Unused
0x22 RegDebounceConfig 0x00
2:0
Debounce time (Cf. §4.5.1)
000: 0.5ms x 2MHz/fOSC
001: 1ms x 2MHz/fOSC
010: 2ms x 2MHz/fOSC
011: 4ms x 2MHz/fOSC
100: 8ms x 2MHz/fOSC
101: 16ms x 2MHz/fOSC
110: 32ms x 2MHz/fOSC
111: 64ms x 2MHz/fOSC
0x23
RegDebounceEnableB
0x00 7:0
Enables debouncing for each [input-configured] IO
0 : Debouncing is disabled
1 : Debouncing is enabled
0x24
RegDebounceEnableA
0x00 7:0
Enables debouncing for each [input-configured] IO
0 : Debouncing is disabled
1 : Debouncing is enabled
7 Reserved
6:4
Auto Sleep time (no key press within this time will set keypad engine to sleep)
000 : OFF
001 : 128ms x 2MHz/fOSC
010 : 256ms x 2MHz/fOSC
011 : 512ms x 2MHz/fOSC
100 : 1sec x 2MHz/fOSC
101 : 2sec x 2MHz/fOSC
110 : 4sec x 2MHz/fOSC
111 : 8sec x 2MHz/fOSC
3 Unused
0x25 RegKeyConfig1 0x00
2:0
Scan time per row (must be set above debounce time).
000 : 1ms x 2MHz/fOSC
001 : 2ms x 2MHz/fOSC
010 : 4ms x 2MHz/fOSC
011 : 8ms x 2MHz/fOSC
100 : 16ms x 2MHz/fOSC
101 : 32ms x 2MHz/fOSC
110 : 64ms x 2MHz/fOSC
111 : 128ms x 2MHz/fOSC
7:6 Unused
5:3
Number of rows (outputs) + key scan enable
000 : Key scan OFF
001 : 2 rows – IO[0:1]
010 : 3 rows – IO[0:2]
011 : 4 rows – IO[0:3]
100 : 5 rows – IO[0:4]
101 : 6 rows – IO[0:5]
110 : 7 rows – IO[0:6]
111 : 8 rows – IO[0:7]
0x26
RegKeyConfig2
0x00
2:0
Number of columns (inputs)
000 : 1 column – IO[8]
001 : 2 columns – IO[8:9]
010 : 3 columns – IO[8:10]
011 : 4 columns – IO[8:11]
100 : 5 columns – IO[8:12]
101 : 6 columns – IO[8:13]
110 : 7 columns – IO[8:14]
111 : 8 columns – IO[8:15]
0x27 RegKeyData1 0xFF 7:0
Column which generated NINT (active low)
Ex: RegKeyData1=11011111 => IO13 has generated NINT
The register is automatically cleared when RegKeyData2 is read.
0x28
RegKeyData2
0xFF 7:0
Row which generated NINT (active low)
Ex: RegKeyData2=11111110 => IO0 has generated NINT
When the register is read both RegKeyData1 & RegKeyData2 are automatically cleared
together with NINT and key scan continues.
7:5 Unused
0xXX
RegTOnX
0x00
4:0
ON Time of IO[X]:
0 : Infinite (Static mode, TOn directly controlled by RegData, Cf §4.8.2)
1 - 15 : TOnX = 64 * RegTOnX * (255/ClkX)
16 - 31 : TOnX = 512 * RegTOnX * (255/ClkX)
0xXX RegIOnX 0xFF 7:0
ON Intensity of IO[X]
- Linear mode : IOnX = RegIOnX
- Logarithmic mode (fading capable IOs only) : IOnX = f(RegIOnX) , Cf §4.8.5