Datasheet

 2008-2011 Microchip Technology Inc. DS39927C-page 19
PIC24F16KA102 FAMILY
2.4 Voltage Regulator Pin (VCAP)
Some of the PIC24F K devices have an internal voltage
regulator. These devices have the voltage regulator
output brought out on the VCAP pin. On the PIC24F K
devices with regulators, a low-ESR (< 5Ω) capacitor is
required on the V
CAP pin to stabilize the voltage
regulator output. The V
CAP pin must not be connected to
V
DD and must use a capacitor of 10 µF connected to
ground. The type can be ceramic or tantalum. Suitable
examples of capacitors are shown in Table 2-1.
Capacitors with equivalent specifications can be used.
Designers may use Figure 2-3 to evaluate ESR
equivalence of candidate devices.
The placement of this capacitor should be close to V
CAP.
It is recommended that the trace length not exceed
0.25 inch (6 mm). Refer to Section 29.0 “Electrical
Characteristics” for additional information.
Refer to Section 29.0 “Electrical Characteristics” for
information on V
DD and VDDCORE.
FIGURE 2-3: FREQUENCY vs. ESR
PERFORMANCE FOR
SUGGESTED V
CAP
Note: This section applies only to PIC24F K
devices with an on-chip voltage regulator.
10
1
0.1
0.01
0.001
0.01 0.1 1 10 100 1000 10,000
Frequency (MHz)
ESR ()
Note: Typical data measurement at 25°C, 0V DC bias.
TABLE 2-1: SUITABLE CAPACITOR EQUIVALENTS
Make Part #
Nominal
Capacitance
Base Tolerance Rated Voltage Temp. Range
TDK C3216X7R1C106K 10 µF ±10% 16V -55 to 125ºC
TDK C3216X5R1C106K 10 µF ±10% 16V -55 to 85ºC
Panasonic ECJ-3YX1C106K 10 µF ±10% 16V -55 to 125ºC
Panasonic ECJ-4YB1C106K 10 µF ±10% 16V -55 to 85ºC
Murata GRM32DR71C106KA01L 10 µF ±10% 16V -55 to 125ºC
Murata GRM31CR61C106KC31L 10 µF ±10% 16V -55 to 85ºC