PIC16HV540-04I/SS Microchip Technology, PIC16HV540-04I/SS Datasheet - Page 36

• Manufacturer Part Number: PIC16HV540-04I/SS
• Description: IC MCU OTP 512X12 20SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16HV540-04I/SS

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 12
• Program Memory Size: 768B (512 x 12)
• Program Memory Type: OTP
• Ram Size: 25 x 8
• Voltage - Supply (vcc/vdd): 3.5 V ~ 15 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SSOP
• Processor Series: PIC16H
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 25 B
• Maximum Clock Frequency: 4 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 8
• Operating Supply Voltage: 3.5 V to 15 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• For Use With: 309-1016 - ADAPTER 20-SSOP TO 18-DIP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / Rohs Status: Details

PIC16HV540
7.4
The PIC16HV540 incorporates on-chip Power-on
Reset (POR) circuitry which provides an internal chip
reset for most power-up situations. To use this feature,
the user merely ties the MCLR/V
plified block diagram of the on-chip Power-on Reset cir-
cuit is shown in Figure 7-7.
The Power-on Reset circuit and the Device Reset
Timer (Section 7.5) circuit are closely related. On
power-up, the reset latch is set and the DRT is reset.
The DRT timer begins counting once it detects MCLR
to be high. After the time-out period, which is typically
18 ms, it will reset the reset latch and thus end the on-
chip reset signal.
A power-up example where MCLR is not tied to V
shown in Figure 7-8. V
before bringing MCLR high. The chip will actually come
out of reset T
In Figure 7-9, the on-chip Power-on Reset feature is
being used (MCLR and V
is stable before the start-up timer times out and there is
no problem in getting a proper reset. However,
Figure 7-10 depicts a problem situation where V
rises too slowly. The time between when the DRT
senses a high on the MCLR
MCLR
is too long. In this situation, when the start-up timer
times out, V
the chip is, therefore, not guaranteed to function cor-
rectly. For such situations, we recommend that external
RC circuits be used to achieve longer POR delay times
(Figure 7-7).
For more information on PIC16HV540 POR, see
Power-Up Considerations - AN522 in the Embedded
Control Handbook.
The POR circuit does not produce an internal reset
when V
DS40197B-page 36
Note:
/
V
DD
PP
Power-On Reset (POR)
declines.
When the device starts normal operation
(exits the reset condition), device operating
parameters (voltage, frequency, tempera-
ture, etc.) must be met to ensure operation.
If these conditions are not met, the device
must be held in reset until the operating
conditions are met.
pin
DD
DRT
(and V
has not reached the V
msec after MCLR goes high.
DD
DD
) actually reach their full value,
DD
is allowed to rise and stabilize
are tied together). The V
/
V
PP
PP
pin
pin to V
DD
, and when the
(min) value and
DD
. A sim-
DD
Preliminary
DD
DD
is
FIGURE 7-7:
• External Power-On Reset circuit is required only if
• R < 40 k
• R1 = 100
V
charge the capacitor quickly when V
down.
age drop across R does not violate the device elec-
trical specification.
MCLR from external capacitor C in the event of
MCLR pin breakdown due to Electrostatic Dis-
charge (ESD) or Electrical Overstress (EOS).
DD
V
DD
power-up is too slow. The diode D helps dis-
D
is recommended to make sure that volt-
to 1 k
V
DD
EXTERNAL POWER-ON
RESET CIRCUIT (FOR SLOW
V
R
DD
C
will limit any current flowing into
POWER-UP)
2000 Microchip Technology Inc.
R1
PIC16HV540
MCLR
DD
powers