EVALUATION KIT AVAILABLE MAX17598/MAX17599 Low I , Wide-Input Range, Active Clamp Q Current-Mode PWM Controllers General Description Benefits and Features The MAX17598/MAX17599 low I , active clamp current- S Active Clamp, Peak Current-Mode Forward PWM Q mode PWM controllers contain all the control circuitry Controller required for the design of wide-input isolated/non-iso- S 20FA Startup Current in UVLO lated forward-converter industrial power supplies. The S 4.5V to 36V Input-Supply Operating Range MAX17598 is well-suited for universal input (rectified 85V (MAX17599) AC to 265V AC) or telecom (36V DC to 72V DC) power S Programmable Input Undervoltage Lockout supplies. The MAX17599 is optimized for low-voltage industrial supplies (4.5V DC to 36V DC). S Programmable Input Overvoltage Protection The devices include an AUX driver that drives an aux- S Programmable 100kHz to 1MHz Switching iliary MOSFET (clamp switch) that helps implement the Frequency active-clamp transformer reset topology for forward con- S Switching Frequency Synchronization verters. Such a reset topology has several advantages S Programmable Frequency Dithering for Low EMI including reduced voltage stress on the switches, trans- Spread-Spectrum Operation former size reduction due to larger allowable flux swing, and improved efficiency due to elimination of dissipative S Programmable Dead Time snubber circuitry. Programmable dead time between the S Adjustable Soft-Start AUX and main driver allows for zero voltage switching (ZVS). S Programmable Slope Compensation The switching frequency is programmable from 100kHz S Fast Cycle-by-Cycle Peak-Current-Limit to 1MHz for the devices with an accuracy of Q8% using an external resistor. This allows optimization of S 70ns Internal Leading-Edge Current-Sense the magnetic and filter components, resulting in com- Blanking pact, cost-effective isolated/nonisolated power supplies. S Hiccup Mode Output Short-Circuit Protection For EMI-sensitive applications, the ICs incorporate a S Soft-Stop for Well-Controlled Clamp Capacitor programmable frequency-dithering scheme, enabling Discharge low-EMI spread-spectrum operation. S Negative Clamp-Switch Current Limit An input undervoltage lockout (EN/UVLO) is provided for programming input-supply start voltage, and to ensure S 3mm x 3mm, Lead-Free 16-Pin TQFN proper operation during brownout conditions. EN/UVLO S -40C to +125C Operating Temperature Range input is also used to turn on/off the ICs. Input overvoltage (OVI) protection scheme is provided to make sure that Applications the regulator shuts down when input supply exceeds its maximum allowed value. Telecom and Datacom Power Supplies To control inrush current, the devices incorporate an SS pin Isolated Battery Chargers to set the soft-start time for the regulators. Power dissipa- Servers and Embedded Computing tion under fault conditions is minimized by hiccup overcur- Industrial Power Supplies rent protection (hiccup mode). Soft-stop feature provides safe discharging of the clamp capacitor when the device is turned off, and allows the controller to restart in a well- controlled manner. Additionally, negative current limit is Ordering Information appears at end of data sheet. provided in the current-sense circuitry, helping limit clamp switch current under dynamic operating conditions. For related parts and recommended products to use with this part, refer to www.maximintegrated.com/MAX17598.related. SYNC feature is provided to synchronize multiple convert- ers to a common external clock in noise-sensitive applica- tions. Overtemperature fault triggers thermal shutdown for reliable protection of the device. The ICs are available in a 16-pin, TQFN package with 0.5 mm lead spacing. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maximintegrated.com. 19-6179 Rev 2 4/14MAX17598/MAX17599 Low I , Wide-Input Range, Active Clamp Q Current-Mode PWM Controllers ABSOLUTE MAXIMUM RATINGS V (MAX17599 only) ............................................-0.3V to +40V Maximum Input/Output Current (Continuous) IN V to SGND V , V ......................................................................100mA DRV IN DRV (MAX17598 Only) ..............................................-0.3V to +16V NDRV (pulsed for less than 100ns) .........................+0.9A/-1.5A (MAX17599 Only) ................................................-0.3V to +6V AUXDRV (pulsed for less than 100ns) .....................+0.3A/-0.7A EN/UVLO to SGND .....................................-0.3V to (V + 0.3V) Continuous Power Dissipation (T = +70NC) IN A NDRV, AUXDRV to PGND .......................-0.3V to (V + 0.3V) TQFN (derate 20.8mW/C above 70C) ....................1666mW DRV OVI, RT, DITHER, COMP, SS, FB, Operating Temperature Range ........................ -40C to +125C SLOPE, DT to SGND ..........................................-0.3V to +6V Maximum Junction Temperature .....................................+150C CS to SGND ............................................................-0.8V to +6V Storage Temperature Range ............................ -65C to +150C PGND to SGND ....................................................-0.3V to +0.3V Lead Temperature (soldering, 10s) ................................+300C Soldering Temperature (reflow) ......................................+260C PACKAGE THERMAL CHARACTERISTICS (Note 1) TQFN Junction-to-Case Thermal Resistance (q ) .................7C/W JC Junction-to-Ambient Thermal Resistance (q ) ..........48C/W JA Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional opera- tion of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 12V (for MAX17598, bring V up to 21V for startup), V = V = V = V = V = V = 0V, V = +2V, OVI SGND IN IN CS DITHER FB PGND EN/UVLO AUXDRV = NDRV = SS = COMP = SLOPE = unconnected, R = 25kI, R = 10kI, C = 1FF, C = 1FF, T = T = -40NC to RT DT VIN VDRV A J +125NC, unless otherwise noted. Typical values are at T = T = +25NC.) (Note 2) A J PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS INPUT SUPPLY (V ) IN MAX17598 8 29 V Voltage Range V V IN IN MAX17599 4.5 36 MAX17598 18.5 20 21.5 V Bootstrap UVLO Wakeup V IN rising V IN IN-UVR MAX17599 3.8 4.1 4.4 MAX17598 6.5 7 7.5 V Bootstrap UVLO IN V IN falling V IN-UVF Shutdown Level MAX17599 3.6 3.9 4.2 V Supply Startup Current I IN IN- V < UVLO 20 32 FA IN (under UVLO) STARTUP V Supply Shutdown IN I V = 0V 20 32 FA IN-SH EN Current V Supply Current I Switching, f = 400kHz 2 mA IN IN-SW SW V = 0V, I = 2mA sinking EN IN V Clamp Voltage V 30 33 36 V IN INC (MAX17598) (Note 3) ENANBLE (EN) V V rising 1.16 1.21 1.26 ENR EN EN Threshold V V V falling 1.1 1.15 1.20 ENF EN EN Input Leakage Current I V = 1.5V, T = +25NC -100 +100 nA EN EN A Maxim Integrated 2