PSB21473FV13XT Infineon Technologies, PSB21473FV13XT Datasheet - Page 509

• Manufacturer Part Number: PSB21473FV13XT
• Manufacturer: Infineon Technologies

Specifications of PSB21473FV13XT

• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3.135V
• Operating Supply Voltage (max): 3.6V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 144
• Lead Free Status / RoHS Status: Compliant

The behaviour of the keypadscanner is such that the SREGx registers contain the result
of the current scan cycle and an interrupt is always generated whenever a change of the
register value is detected within two successive scan cycles (to prevent bouncing).
If two pressed keys are not released in the same scan cycle (e.g. cycle #5 and #6 in the
example below), an interrupt is also generated, i.e. releasing a key is also indicated by
an interrupt (cycle #8).
Figure 21-3 Behaviour of the Keypad Scanner
The scan results are stored in the SREGx registers with a mapping as shown in Figure
21-4.
•
Figure 21-4 Buffer Structure
Data Sheet
0
1
2
3
4
5
6
7
8
9
S ca n C ycle
P re sse d K e ys
In te rru p t
R e g iste r C o n te n t
S R E G x
SREG0
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
SREG1
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
1
1
XXX
XXX
XXX
XXX
XXX
XXX
XXX
SREG23
2
2
XXX
XXX
XXX
XXX
XXX
XXX
3
1
2
XXX
XXX
XXX
XXX
XXX
509
SREG45
4
1
2
1
2
XXX
XXX
XXX
XXX
5
1
Terminal Specific Functions
XXX
XXX
XXX
6
1
1
SREG6789
XXX
XXX
7
PSB 21473
XXX
ke ysca n
2003-03-31
INCA-D
8