MAX15059 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – 76V, 300mW Boost Converter and Current Monitor for APD Bias Applications

19-5132; Rev 1; 3/10
EVAALVUAAILTAIOBNLEKIT
76V, 300mW Boost Converter and Current
Monitor for APD Bias Applications
General Description
The MAX15059 constant-frequency pulse-width modu-
lating (PWM) step-up DC-DC converter features an
internal switch and a high-side current monitor with high-
speed adjustable current limiting. This device is capable
of generating output voltages up to 76V (300mW for
the MAX15059A and 200mW for the MAX15059B) and
provides current monitoring up to 4mA. The MAX15059
operates from 2.8V to 5.5V.
The constant-frequency (400kHz) current-mode PWM
architecture provides low-noise-output voltage that is
easy to filter. A high-voltage internal power MOSFET
allows this device to boost output voltages up to 76V.
Internal soft-start circuitry limits the input current when
the boost converter starts. The MAX15059 features a
shutdown mode to save power.
The MAX15059 includes a current monitor with more
than three decades of dynamic range and monitors
current ranging from 500nA to 4mA with high accuracy.
Resistor-adjustable current limiting protects the APD
from optical power transients. A clamp diode protects
the monitor’s output from overvoltage conditions. Other
protection features include cycle-by-cycle current limit-
ing of the boost converter switch, undervoltage lockout
(UVLO), and thermal shutdown if the die temperature
reaches +150NC.
The MAX15059 is available in a thermally enhanced,
lead-free, 16-pin TQFN-EP package and operates over
the -40NC to +85NC temperature range.
Applications
Avalanche Photodiode Biasing and Monitoring
PIN Diode Bias Supply
Low-Noise Varactor Diode Bias Supply
FBON Modules
GPON Modules
Features
S Input Voltage Range: +2.8V to +5.5V
S Wide Output-Voltage Range from (VIN + 5V) to 76V
S Internal 1I (typ) 80V MOSFET
S Boost Converter Output Power: 300mW
S 200mW Version Available for Smaller Inductor
S Accurate Q5% (1:1 and 5:1) High-Side Current
Monitor
S Resistor-Adjustable Ultra-Fast APD Current Limit
(1µs Response Time)
S Open-Drain Current-Limit Indicator Flag
S 400kHz Fixed-Switching Frequency
S Constant PWM Frequency Provides Easy Filtering
in Low-Noise Applications
S Internal Soft-Start
S 2µA (max) Shutdown Current
S -40NC to +85NC Temperature Range
S Small, Thermally Enhanced, 3mm x 3mm, Lead-
Free, 16-Pin TQFN-EP Package
Ordering Information
PART
MAXIMUM
POWER
(mW)
IAPD:
I_MOUT
PIN-
PACKAGE
MAX15059AETE+
300
1:1 16 TQFN-EP*
MAX15059BETE+
200
5:1 16 TQFN-EP*
Note: All devices operate over the -40°C to +85°C temperature
range.
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Typical Operating Circuit
VIN = 2.8V
TO 5.5V
IN
CNTRL
L1
4.7µH
D1
CIN
1µF
LX
COUT
0.1µF
PGND
RLIM
2.87kI
BIAS
MAX15059
FB
SHDN
RLIM
ILIM
VDD
CLAMP
SGND
APD MOUT
APD
TIA
RMOUT
1kI
VOUT
(76V MAX)
R2
348kI
RADJ
R1
6.34kI
GPIO
GPIO ^DAC
VDD
µC
ADC
CMOUT
OPTIONAL
(10nF)
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