UT61E digital multimeter schematics and integrated circuit datasheet

Uni-t UT61E Multimeter - Circuit diagram

ES51922 application circuit for ES51922 datasheet.

ES51922 application circuit.png

In UT61E 1some features of ES51922 are not used and can be enabled by simple hardware diy:

112 APOSEL I Idle time selection for auto power off feature.

58 SLEEP O Sleep mode indicator, asserts low in SLEEP mode.

105 BKOUT O If BKLIT function is enabled, this pin will change from –3V to +3V
For 60 sec, once press BKLIT pin again within 60 sec, this pin will
Change back to –3V

102 BKLIT I Back light function. Pulse low to set BKOUT pin output.

113 BKSEL I Set to V- to change the backlight idle time from 60 sec. to 180 sec.

UT61 series Operation manual.