SCPS285A november 2022 – august 2023 TCAL9539-Q1
PRODUCTION DATA
In the event of a glitch or data corruption, TCAL9539-Q1 can be reset to its default conditions by using the power-on reset feature. Power-on reset requires that the device go through a power cycle to be completely reset. This reset also happens when the device is powered on for the first time in an application.
The two types of power-on reset are shown in Figure 9-6 and Figure 9-7.
Table 9-2 specifies the performance of the power-on reset feature for TCAL9539-Q1 for both types of power-on reset.
PARAMETER(1)(2) | MIN | TYP | MAX | UNIT | ||
---|---|---|---|---|---|---|
tFT | Fall rate | See Figure 9-6 | 0.1 | 2000 | ms | |
tRT | Rise rate | See Figure 9-6 | 0.1 | 2000 | ms | |
tTRR_GND | Time to re-ramp (when VCC drops to GND) | See Figure 9-6 | 1 | μs | ||
tTRR_POR50 | Time to re-ramp (when VCC drops to VPOR_MIN – 50 mV) | See Figure 9-7 | 1 | μs | ||
VCC_GH | Level that V can glitch down to, but not cause a functional disruption when V = 1 μs | See Figure 9-8 | 1.0 | V | ||
tGW | Glitch width that will not cause a functional disruption when V = 0.5 × VCCx | See Figure 9-8 | 10 | μs | ||
VPORF | Voltage trip point of POR on falling VCC | 0.6 | V | |||
VPORR | Voltage trip point of POR on rising VCC | 1.0 | V |
Glitches in the power supply can also affect the power-on reset performance of this device. The glitch width (VCC_GW) and height (VCC_GH) are dependent on each other. The bypass capacitance, source impedance, and device impedance are factors that affect power-on reset performance. Figure 9-8 and Table 9-2 provide more information on how to measure these specifications.
VPOR is critical to the power-on reset. VPOR is the voltage level at which the reset condition is released and all the registers and the I2C/SMBus state machine are initialized to their default states. The value of VPOR differs based on the V being lowered to or from 0. Figure 9-9 and Table 9-2 provide more details on this specification.