CDR

IPHASE

DIN2

ITRIP

DIN1

OUT1_

OUT2_

FWD

FWD

CASE A) CDR OUTPUT FWD MODE NO PWM

CDR

IPHASE

DIN2

ITRIP

DIN1

OUT1_

OUT2_

FWD

FWD

CASE B) CDR OUTPUT WITH PWM

CDR

IPHASE

DIN2

ITRIP

DIN1

OUT1_

OUT2_

FWD

FWD

CASE C) CDR OUTPUT WITH PWM INTERRUP

FWD

FIXED tOFF

CDR ASSERTED

CDR ASSERTED

FIXED tOFF

FIXED tOFF

CDR ASSERTED

FIXED tOFF

CDR ASSERTED

FIXED tOFF

FIXED tOFF

CDR

ASSERTED

CDR

ASSERTED

CDR

ASSERTED

Figure 2. CDR Monitor Timing Diagram

Setting the Decay Mode

Two logic input pins allow to set the Decay Mode during tOFF. The MAX22211 supports slow, fast, and two different

mixed decay modes.

Table 3 shows the Truth Table for the Decay Mode selection.

Table 3. Decay Mode Truth Table

DECAY2

DECAY1

DECAY MODE

0

0

Slow

MAX22211

36V, 3.8A Two H-Bridge for Dual Brushed or

Single Stepper Motor Drive

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