MAX15059 Datasheet, PDF (10/15 Pages) Maxim Integrated Products – 76V, 300mW Boost Converter and Current Monitor for APD Bias Applications

76V, 300mW Boost Converter and Current
Monitor for APD Bias Applications
PIN
12
13
14, 15
—
NAME
APD
BIAS
LX
EP
Pin Description (continued)
FUNCTION
Reference Current Output. APD provides the source current to the cathode of the photodiode.
Bias-Voltage Input. Connect BIAS to the boost converter output (VOUT) either directly or through a
lowpass filter for ripple attenuation. BIAS provides the voltage bias for the current monitor and is the
current source for APD.
Drain of Internal 80V n-Channel DMOS. Connect inductor to LX. Minimize the trace area at LX to reduce
switching-noise emission.
Exposed Paddle. Connect to a large copper plane at the SGND and PGND potential to improve thermal
dissipation. Do not use as the only ground connection.
Functional Diagram
FB
-A
V_REF
CNTRL
MUX +A
SGND
-C
+C
VREF
REFERENCE
COMPARATOR
OUTPUT ERROR
AND CURRENT COMPARATOR
SOFT-
START
PEAK
CURRENT-LIMIT
COMPARATOR
SWITCH
CONTROL
LOGIC
VREF
80V
DMOS
SWITCH
CURRENT
SENSE
BIAS
THERMAL
1X
AND REF
SHUTDOWN
IN
UVLO
CONTROL
MONITOR
CURRENT-
LIMIT
ADJUSTMENT
CLK
OSCILLATOR
400kHz
MAX15059
1X (A)
5X (B)
CURRENT
LIMIT
LX
PGND
CLAMP
MOUT
RLIM
APD
ILIM
SHDN
BIAS
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