Datasheet

ManualsBrandsMICROCHIP TECHNOLOGY ManualsMicrocontrollers, Microprocessors & QuartzesEmbedded microcontroller SSOP 28 8-Bit 20 MHz I/O number 24

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PIC16F913/914/916/917/946

11.1 PLVD Operation

To setup the PLVD for operation, the following steps

must be taken:

• Enable the module by setting the LVDEN bit of the

LVDCON register.

• Configure the trip point by setting the LVDL<2:0>

bits of the LVDCON register.

• Wait for the reference voltage to become stable.

Refer to Section 11.4 “Stable Reference

Indication”.

• Clear the LVDIF bit of the PIR2 register.

The LVDIF bit will be set when V

DD falls below the

PLVD trip point. The LVDIF bit remains set until cleared

by software. Refer to Figure 11-2.

11.2 Programmable Trip Point

The PLVD trip point is selectable from one of eight

voltage levels. The LVDL bits of the LVDCON register

select the trip point. Refer to Register 11-1 for the

available PLVD trip points.

11.3 Interrupt on Falling VDD

When VDD falls below the PLVD trip point, the falling

edge detector will set the LVDIF bit. See Figure 11-2.

An interrupt will be generated if the following bits are

also set:

• GIE and PEIE bits of the INTCON register

• LVDIE bit of the PIE2 register

The LVDIF bit must be cleared by software. An interrupt

can be generated from a simulated PLVD event when

the LVDIF bit is set by software.

11.4 Stable Reference Indication

When the PLVD module is enabled, the reference volt-

age must be allowed to stabilize before the PLVD will

provide a valid result. Refer to Section 19.0 “Electri-

cal Specifications”, Table 19-13, for the stabilization

time.

When the HFINTOSC is running, the IRVST bit of the

LVDCON register indicates the stability of the voltage

reference. The voltage reference is stable when the

IRVST bit is set.

11.5 Operation During Sleep

To wake from Sleep, set the LVDIE bit of the PIE2

the LVDIE and PEIE bits are set, the device will wake

from Sleep and execute the next instruction. If the GIE

bit is also set, the program will call the Interrupt Service

Routine upon completion of the first instruction after

waking from Sleep.