Click here for production status of specific part numbers. MAX17577EVKIT , MAX17578EVKIT Evaluate: MAX17577 and MAX17578 Evaluation Kits in -12V and -5V Output-Voltage Applications General Description Features The MAX17577EVKIT and MAX17578EVKIT evalua- Operates Over a Wide Input Range tion kits (EV kits) provide a proven design to evaluate the MAX17577EVKIT : V = -12V, I = 0.8A, OUT1 OUT1 MAX17577 and MAX17578 high-efficiency, high-voltage, V Range = 16V to 48V IN1 MAX17578EVKIT : V = -5V, I = 1A, inverting, Himalaya synchronous DC-DC converters. The OUT2 OUT2 devices generate output voltages (V ) from -0.9V to V Range = 16V to 55V OUT IN2 -36V and can deliver up to 1A of load current from a wide Enable/UVLO Input, Resistor Programmable UVLO 4.5V to 60V- V input voltage range. OUT Threshold The MAX17577EVKIT EV kit generates -12V output Adjustable Soft-Start Time (V ) at load currents up to 0.8A from a 16V to 48V OUT1 RESET Output with a Pull-Up Resistor to an External input supply and operates at 600kHz switching frequency. Supply This EV kit configuration features MAX17577 that oper- System Ground Interfaced EN/UVLO and RESET ates in continuous conduction mode (CCM) at all loads, Pins thus, providing a constant frequency operation. Overcurrent and Overtemperature Protection The MAX17578EVKIT EV kit generates -5V output (V ) at load currents up to 1A from a 16V to 55V input OUT2 Proven PCB Layout supply and operates at 600kHz switching frequency. This Fully Assembled and Tested EV kit configuration features MAX17578 that operates in Complies with CISPR32 (EN55032) Class B discontinuous conduction mode (DCM) for superior effi- Conducted and Radiated Emissions ciency at light loads. The EV kits are configured for optimum efficiency and component size. The EV kits feature programmable enable and input undervoltage-lockout (UVLO), soft- start, open-drain RESET signal and external clock syn- Ordering Information appears at end of data sheet. chronization. The EV kits also provide a good layout example, which are optimized for conducted, radiated EMI, and thermal performance. For more details about the device Benefits and Features, refer to the MAX17577, MAX17578 IC data sheet. 319-100646 Rev 0 12/20MAX17577EVKIT , MAX17578EVKIT Evaluate: MAX17577 and MAX17578 Evaluation Kits in -12V and -5V Output-Voltage Applications of typical application circuits of the two devices. Each of Quick Start these circuits are electrically isolated from each other Recommended Equipment and hosted on the same PCB. Each of the devices can MAX17577EVKIT , MAX17578EVKIT be evaluated by powering them from their respective input pins. Individual device settings can be adjusted 60V, 1.5A DC input power supply to evaluate their performance under different operating 5V, 10mA DC input power supply conditions. Loads capable of sinking 1A at -5V and 0.8A at -12V Soft-Start Input (SS) 2 Digital Multimeters (DMM) The EV kits offer an adjustable soft-start function to limit Equipment Setup and Test Procedure inrush current during startup. The soft-start time is adjust- ed by the value of external soft-start capacitor connected The EV kits are fully assembled and tested. between SS and SOUT pins. The selected output capaci- Use the following steps to verify and test individual device tance (C ) and the output voltage (V ) determine OUT OUT operation. the minimum required soft-start capacitor C (C115, SS Caution: Do not turn on the power supply until all C215) as follows: connections are completed. -6 C 28 x 10 x C x V SS OUT OUT 1) Set the 60V input power supply at a voltage between The soft-start time (t ) is related to the capacitor con- SS 16V and 48V for MAX17577EVKIT or between 16V nected at SS (C ) by the following equation: SS and 55V for MAX17578EVKIT . Disable the power supply. C SS 2) Connect the positive terminal of the 60V power sup- t = SS 6 5.55 10 ply to the VIN PCB pad and the negative terminal to the nearest GND PCB pad. For example, to program a 1ms soft-start time, a 5600pF 3) Connect the positive terminal of the 5V power supply capacitor should be connected from the SS pin to SOUT. to the VEXT PCB pad and the negative terminal to the nearest GND PCB pad. Set the voltage at 5V. Enable/Undervoltage-Lockout (EN/UVLO) 4) Connect the positive terminal of the corresponding Programming load to the GND PCB pad and the negative terminal The MAX17577 and MAX17578 offer an Enable and to the nearest VOUT PCB pad. adjustable input undervoltage-lockout feature. In these 5) Connect one DVM across the VOUT PCB pad and EV kits, for normal operation, leave the EN/UVLO jump- the nearest GND PCB pad, and the another DVM ers (JU101, JU201) open. When jumpers are left open, across the RESET pad and GND pad. the MAX17577 and MAX17578 are enabled when the 6) Verify that no shunts are installed on jumpers. input voltage rises above 15.5V. To disable the devices, (JU101, JU201) (see Table 1 for details) install shunts across pins 23 on the jumpers (JU101, 7) Turn on the DC power supply. JU201). See Table 1 for jumper (JU101, JU201) settings. 8) Enable the load. The EN/UVLO PCB pad on the EV kits support external 9) Ensure the input voltage to be above 15.5V which is Enable/Disable control of the device. Leave the jumpers the EN/UVLO rising threshold. open when external Enable/Disable control is desired. 10) Verify that the DVM across the output terminal A potential divider formed by the resistors R UVL TOP displays -12V for MAX17577EVKIT or -5V for (R101, R201) and R (R102, R202) at the EN/ UVL BOT MAX17578EVKIT . UVLO pin sets the input voltage (V ) above which the INU 11) Verify that the DVM across the RESET pad and GND converter is enabled when the jumpers are left open. displays 5V. Choose R to be 3.32M (max), and then calcu- 12) Reduce the input voltage to 12V which is below the UVL TOP late R as follows: EN/UVLO falling threshold. UVL BOT 13) Verify that both the DVMs displays 0V. 1.229 R UVL TOP 14) Disable the input power supply. R = UVL BOT (V 1.229) INU Detailed Description of Hardware The MAX17577EVKIT and MAX17578EVKIT EV kits where, R is in M. For more details about UVL BOT are designed to demonstrate the salient features of Setting the Input Undervoltage-Lockout Level, refer to the MAX17577 and MAX17578 devices. The EV kits consist MAX17577, MAX17578 IC data sheet. Maxim Integrated 2 www.maximintegrated.com