GENERAL DESCRIPTION

The ADL5315 is a wide input current range, precision high-side current mirror featuring a stable and user-adjustable input voltage. It is optimized for use with PIN photodiodes, but its flexibility and wide operating range make it suitable for a broad array of additional applications. Over the 3 nA to 3 mA range, the current sourced from the INPT pin is accurately mirrored with a 1:1 ratio and sourced from the IOUT output pin. In a typical photodiode application, the output drives a current-input logarithmic amplifier to produce a linear-in-dB output representing the optical power incident upon the photodiode.

FEATURES

Accurately mirrors input current (1:1 ratio) over 6 decades

Linearity 1 from 3 nA to 3 mA

Stable mirror input voltage

Voltage held 1 V below supply using internal reference

or can be set externally

Adjustable input current limit

2.7 V to 8 V single-supply operation

Miniature 8-lead LFCSP (2 mm × 3 mm)

APPLICATIONS

Optical power monitoring from a single photodiode

General voltage biasing with precision current monitoring

Voltage-to-current conversion