Datasheet

RESET
Software Reset
1
SCLK
CS
8 1
S 0 0 X X X1 1SDI
ControlBits
S
ControlBits
8
t
D(RESET)
t
SU(SCLKF-CSR)
t
SU(CSF-SCLK1R)
A2 A1 A0
MODE
SER/
DFR
PD1 PD0
SureSet
0
1
0 0 0 0
0
1
SPILockup 24-BitSureSetSequence
CS
SCLK
SDI
1
0
0
1
Reset
NormalOperation
TSC2008
www.ti.com .......................................................................................................................................................... SBAS406B – JUNE 2008 – REVISED MARCH 2009
The TSC2008 can be reset with three different methods: power-on reset (POR), software reset, and the
proprietary SureSet function. The configuration bits (see Table 3 , bit[3:1]) accessible through the setup command
('010') are reset to the respective default values listed in Table 3 after any reset occurs (POR, software reset, or
SureSet).
The TSC2008 has a software reset command that can be issued by submitting the 8-bit command '1010 0001'
via the SPI, as shown in Figure 35 . This command resets the device to the default configuration. All the settings
in the control byte are reset to default values (see Table 2 and Table 3 ).
Figure 35. Software Reset Timing
Table 8. Timing Requirements for Figure 35
PARAMETER TEST CONDITIONS MIN MAX UNIT
1.2V ≤ VDD < 1.6V 22 ns
t
SU(CSF-SCLK1R)
Enable lead time
1.6 ≤ VDD < 3.6V 14 ns
1.2V ≤ VDD < 1.6V 50 ns
t
SU(SCLKF-CSR)
Enable lag time
1.6 ≤ VDD < 3.6V 20 ns
t
D(RESET)
Reset period requirement 200 ns
The TSC2008 uses SureSet, a unique reset function. SureSet works in the same way as a hardware reset
except that it does not require a dedicated reset pin on the device. SureSet works independently from the
software reset and power-on reset. For example, the software reset works only after the interface (internal state
machine) is fully functional, whereas SureSet works without the interface. In the unlikely event that the host
becomes out-of-sync with the TSC2008, and forcing CS high does not reset the state machine, the host can
submit a 24-bit sequence (0x06D926) that resets the device to a default state (the same as the power-up state),
as shown in Figure 36 . In order to reset the TSC2008, the device must be selected ( CS low) before submitting
this sequence.
Figure 36. SureSet Timing
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Product Folder Link(s): TSC2008