ver. 1.7

12/01/12

21

ES51997(60000counts)

DMM Analog front end

Status Flag

LDUTY=1

LDUTY=0

Duty cycle (<60kHz)

10000-D2*10000/D3

D2*10000/D3

The status flags HF & LF are used for fast judgment of proper range. If frequency input is

larger than 7 kHz, HF will be active. If frequency input is floating or frequency detected too

low, LF will be active.

Auto range consideration for MPU by using Status Flags of frequency mode

Flag

F_FIN=0

F_FIN=1

F_FIN=1

Range

LF=0

LF=1*

HF=LF=0

HF=1**

60.000Hz

600.00Hz

6.0000KHz

Data and Range

is not necessary

to be updated

Hz/Duty=0

Change range

depends on data

computed

Set range to

60.000kHz

range

Set range to

60.000Hz range

60.000KHz

600.00KHz

6.0000MHz

60.000MHz

Change range

depends on data

computed

*Note: LF=1 @ 60Hz range implies the frequency is not available to be measured. The Hz/Duty readings

should be set to zero.

**Note: When ACV+Hz/ACA+Hz/ADP+Hz mode is selected, the HF status should be ignored. Change range

depends on data calculation result.

Duty cycle mode range (Input sensitivity > 2Vpp @ duty cycle = 5.0% & 95.0%)

Freq. range

Duty range*

60.000Hz

600.00Hz

5.0% - 95.0%

6.0000KHz

10.0 % - 90.0%

60.000KHz

20.0% – 80.0%

*Note: Duty range for AC+Hz(%) is 20% ~ 80%.