Diodes ZDS1009 - Manual

ISSUE 2 - JANUARY 2000
ZDS1009
SM-8 COMPLEMENTARY CURRENT MIRROR
1
FEATURES
•
Excellent Temperature Tracking Characteristics
•
Compact Cost Effective Solution
• Simplifies Circuit Implementation
• Broad application base from
Single Cell Li-ion High Side Current sense chargers to
Multi-cell Lead-Acid systems
•
Only 4 Connections required
DESCRIPTION
The ZDS1009 current mirror has been developed
specifically for high side, current sense plus level
translation applications and as such will find a broad
a p p l i c a t i o n s
b a s e i n c l u d i n g b a t t e r y c h a r g e
management, DC motor control and over current
monitoring functions. It is of particular interest for
current sense applications for feedback purposes in fast
battery chargers for Li-Ion cell based systems.
The device functions by sensing the voltage developed
across an external (user defined) high side current
sense resistor, and by an arrangement of current
mirrors refer this sensed voltage, with or without
multiplication, to a low side referenced signal. This
signal can then be used, for example, to close the
control loop to a controller IC, for a DC-DC converter
providing charge to a battery.
TYPICAL APPLICATION CIRCUIT
V IR
R
R sense 2
4
1
=
For balance R3=R4
eg
R2=100m Ω
R1=R3=R4=100
Ω
V
sense
sensitivity = 100mV/A
SM-8
(8 LEAD SOT223)
SCHEMATIC DIAGRAM
CONNECTION DIAGRAM