Datasheet

2011-2013 Microchip Technology Inc. DS70657G-page 423
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X AND PIC24EPXXXGP/MC20X
FIGURE 30-13: QEI MODULE INDEX PULSE TIMING CHARACTERISTICS
(dsPIC33EPXXXMC20X/50X and PIC24EPXXXMC20X DEVICES ONLY)
QEA
(input)
Ungated
Index
QEB
(input)
TQ55
Index Internal
Position Counter
Reset
TQ50
TQ51
TABLE 30-32: QEI INDEX PULSE TIMING REQUIREMENTS
(dsPIC33EPXXXMC20X/50X and PIC24EPXXXMC20X DEVICES ONLY)
AC CHARACTERISTICS
Standard Operating Conditions: 3.0V to 3.6V
(unless otherwise stated)
Operating temperature -40°C TA +85°C for Industrial
-40°C T
A +125°C for Extended
Param
No.
Symbol Characteristic
(1)
Min. Max. Units Conditions
TQ50 TqiL Filter Time to Recognize Low,
with Digital Filter
3 * N * T
CY ns N = 1, 2, 4, 16, 32, 64,
128 and 256 (Note 2)
TQ51 TqiH Filter Time to Recognize High,
with Digital Filter
3 * N * T
CY ns N = 1, 2, 4, 16, 32, 64,
128 and 256 (Note 2)
TQ55 Tqidxr Index Pulse Recognized to Position
Counter Reset (ungated index)
3 T
CY —ns
Note 1: These parameters are characterized but not tested in manufacturing.
2: Alignment of index pulses to QEA and QEB is shown for position counter Reset timing only. Shown for
forward direction only (QEA leads QEB). Same timing applies for reverse direction (QEA lags QEB) but
index pulse recognition occurs on the falling edge.