QT60248-ASG Atmel, QT60248-ASG Datasheet - Page 13

• Manufacturer Part Number: QT60248-ASG
• Description: IC SENSOR QMATRIX 24CHAN 32TQFP
• Manufacturer: Atmel
• Series: QMatrix™, QProx™r
• Type: Capacitiver

Specifications of QT60248-ASG

• Number Of Inputs/keys: 24 Key
• Resolution (bits): 9, 11 b
• Data Interface: Serial, SPI™
• Voltage - Supply: 3 V ~ 5 V
• Current - Supply: 25mA
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 32-TQFP, 32-VQFP
• Output Type: Logic
• Interface: SPI
• Input Type: Logic
• Operating Supply Voltage: 3 V to 5 V
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• For Use With: 427-1087 - BOARD EVAL QT60248-AS QMATRIX
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 427-1108

4.6 Report 1st Key - 0x06
Reports the first or only key to be touched, plus indicates if
there are yet other keys that are also touched.
The return bits are as follows:
Bits 4..0 encode for the first detected key in range 0..23. If no
keys are active, these 5 bits are all 1’s (0x1F, 31 decimal when
bits 5, 6, 7 are masked off). Disabled keys do not report as
active and do not generate an error flag in bit 6, even if they are
reporting an error via command 0x8k.
If 2 or more keys in detection, bit 7 is set and the host should
interrogate the part via the 0x07 command to read out all the
key detections. This one command should be the dominant
interrogation command in the host interface; further commands
can be issued if the response to 0x06 warrants it.
A CRC byte is appended to the response; this CRC folds in the
command 0x06 itself initially.
4.7 Report Detections for All Keys - 0x07
Returns three bytes which indicate all keys in detection if any,
as a bitfield; active keys report as 1’s.. Key 0 reports in bit 0 of
the first byte returned; key 23 is reported in bit 7 of the last byte
returned. See Table 4.1 and Table 5.2. Disabled keys report as
inactive (0).
A CRC byte is appended to the response; this CRC folds in the
command 0x07 itself initially.
4.8 Report Error Flags for All Keys - 0x0b
Returns three bytes which show error flags as a bitfield for all
keys. Key 0 reports in bit 0 of the first byte returned; key 23 is
reported in bit 7 of the last byte returned. See Table 4.1 and
Table 5.2.
A key that is in calibration also is reported as an error in the
response. The error flag is self-cleared once the key
successfully exits from calibration.
Important note: These error bits exclude FMEA error flags.
A CRC byte is appended to the response; this CRC folds in the
command 0x0b itself initially.
lQ
Table 4.1 Bits for key reporting and numbering
Key #
Byte Number
Returned
(Y line #)
BIT
7
6
5
4
3
2
1
0
0
1
2
15
23
7
7
Description
1= more than 1 key is active
1= any error condition is present
Unused
Key bit 4
Key bit 3
Key bit 2
Key bit 1
Key bit 0
14
22
6
6
Bit Number (X line #)
13
21
5
5
12
20
4
4
11
19
3
3
10
18
2
2
17
1
1
9
16
0
0
8
13
4.9 Report FMEA Status - 0x0c
Returns one byte which shows the FMEA error status of the X
and/or Y matrix scan lines. If an X line is in error, the
corresponding bit (below) is set. If a Y line has an FMEA error,
the entire field is set to ones (0xFF).
Due to the physics of matrix wiring, a fault on any Y line will
cause faults to be reported on all X lines as well. It is not
possible to separate out these faults for reporting purposes.
A CRC byte is appended to the response; this CRC folds in the
command 0x0C itself initially.
Sometimes, FMEA errors can occur intermittently, for example
due to momentary power fluctuations. It is advisable to confirm
a true FMEA fault condition by making sure the error flags
persist for a several seconds.
For more information see Section 2.16.
4.10 Dump Setups Block - 0x0d
This command causes the device to dump the entire internal
Setups block back to the host.
If the transfer is not paced faster than 100ms per byte the
transfer will be aborted and the device will time out. This can
happen if the host is also controlling DRDY.
During the transfer, sensing is halted. Sensing is resumed after
the command has finished.
An 8-bit CRC is appended to the response; this CRC is the
same as the Setups table CRC.
4.11 Eeprom CRC - 0x0e
This command returns the 8-bit CRC byte calculated from the
eeprom contents. The CRC sent back is the same CRC that is
appended to the end of the Setups block.
This command requires substantial amounts of time to process
and return a result; it is not recommended to use this command
except perhaps on startup or very infrequently.
No CRC is appended to the response.
4.12 Return Last Command - 0x0f
This command returns the last received command character, in
1’s complement (inverted). If the command is repeated twice or
more, it will return the inversion of 0x0f, 0xf0.
If a prior command was not valid or was corrupted, it will return
the bad command as well. This command also will reset the
communications error flag (Section 4.5).
No CRC is appended to the response.
4.13 Internal Code - 0x10
This command returns a 1-byte internal code.
A CRC byte is appended to the response; this CRC folds in the
command 0x10 itself initially.
4.14 Internal Code - 0x12
This command returns an internal code byte of the part for
factory diagnostic purposes. A response might take as long as
500ms.
No CRC is appended to the response.
b7
X7
b6
X6
b5
X5
b4
X4
QT60248-AS R4.02/0405
b3
X3
b2
X2
b1
X1
b0
X0