TC1301A_08 Datasheet, PDF (19/28 Pages) Microchip Technology – Dual LDO with Microcontroller RESET Function

Junction Temperature Estimate
To estimate the internal junction temperature, the
calculated temperature rise is added to the ambient or
offset temperature. For this example, the worst-case
junction temperature is estimated below:
T_J = T_JRISE + T_A(MAX)
T_J = 83.1°C
Maximum Package Power Dissipation at 50°C
Ambient Temperature
3X3DFN8 (41° C/W Rθ_JA)
P_D(MAX) = (125°C - 50°C) / 41° C/W
P_D(MAX) = 1.83 Watts
MSOP8 (208° C/W Rθ_JA)
P_D(MAX) = (125°C - 50°C) / 208° C/W
P_D(MAX) = 0.360 Watts
7.0 TYPICAL LAYOUT TC1301A
TC1301A/B
FIGURE 7-3:
Example.
3x3 DFN Silk-Screen
8-lead 3X3 DFN physical layout example with bypass
capacitor.
FIGURE 7-1:
MSOP8 Silk Screen Layer.
When doing the physical layout for the TC1301A/B, the
highest priority is placing the input and output
capacitors as close to the device pins as is practical.
Figure 7-1 above represents a typical placement of the
components when using SMT0805 capacitors.
FIGURE 7-2:
MSOP8 Wiring Layer.
A wiring example for the TC1301A is shown. The vias
represent the connection to a ground plane that is
below the wiring layer.
FIGURE 7-4:
Example.
3x3 DFN Top Metal Layer
Vias represent the connection to a ground plane that is
below the wiring layer.
8.0 ADDITIONAL OUTPUT
VOLTAGE AND THRESHOLD
VOLTAGE OPTIONS
8.1 Output Voltage and Threshold
Voltage Range
Table 8-1 describes the range of output voltage options
available for the TC1301A/B. V_OUT1 and V_OUT2 can be
factory preset from 1.5V to 3.3V in 100 mV increments.
The V_DET (TC1301A) or threshold voltage (TC1301B)
can be preset from 2.2V to 3.2V in 10 mV increments.
TABLE 8-1:
CUSTOM OUTPUT VOLTAGE
AND THRESHOLD VOLTAGE
RANGES
V_OUT1
1.5V to 3.3V
V_OUT2
V_DET Threshold
1.5V to 3.3V 2.2V to 3.2V
For a listing of TC1301A/B standard parts, refer to the
Product Identification System on page 25.
© 2008 Microchip Technology Inc.
DS21798C-page 19