Document
19-5132; Rev 1; 3/10
www.DataSheet4U.com
TION KIT EVALUA BLE A IL A V A
76V, 300mW Boost Converter and Current Monitor for APD Bias Applications
General Description
The MAX15059 constant-frequency pulse-width modulating (PWM) step-up DC-DC converter features an internal switch and a high-side current monitor with highspeed 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 limiting 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.
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
Features
MAX15059
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, LeadFree, 16-Pin TQFN-EP Package
Ordering Information
PART MAX15059AETE+ MAX15059BETE+ MAXIMUM POWER (mW) 300 200 IAPD: IMOUT 1:1 5:1 PINPACKAGE 16 TQFN-EP* 16 TQFN-EP*
Applications
Avalanche Photodiode Biasing and Monitoring PIN Diode Bias Supply Low-Noise Varactor Diode Bias Supply FBON Modules GPON Modules
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 L1 4.7µH CIN 1µF IN CNTRL LX PGND BIAS R1 6.34kI D1 VOUT R2 348kI RADJ (76V MAX)
COUT 0.1µF
MAX15059
RLIM RLIM 2.87kI SGND APD APD
FB SHDN ILIM VDD CLAMP MOUT RMOUT 1kI GPIO GPIO VDD DAC
µC
ADC CMOUT OPTIONAL (10nF)
TIA
________________________________________________________________ Maxim Integrated .