Datasheet

dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/X04 AND dsPIC33FJ128MCX02/X04
DS70291G-page 382 © 2007-2012 Microchip Technology Inc.
FIGURE 31-13: QEI MODULE INDEX PULSE TIMING CHARACTERISTICS
QEA
(input)
Ungated
Index
QEB
(input)
TQ55
Index Internal
Position Counter
Reset
TQ50
TQ51
TABLE 31-31: QEI INDEX PULSE TIMING REQUIREMENTS
AC CHARACTERISTICS
Standard Operating Conditions: 3.0V to 3.6V
(unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for Industrial
-40°C ≤ TA ≤ +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 * TCY — 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 TCY —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 falling edge.