MAX687-MAX689 MAXIM [Maxim Integrated Products], MAX687-MAX689 Datasheet
MAX687-MAX689
Related parts for MAX687-MAX689
MAX687-MAX689 Summary of contents
Page 1
... The MAX687/MAX688/MAX689 low-dropout linear regula- tors operate with an input-to-output voltage differential lim- ited only by an external PNP transistor. Outputs are fixed at 3.3V (MAX687/MAX688) or 3.0V (MAX689). The only external components required are a PNP pass transistor and output, compensation, and bypass capacitors. Base drive to the external transistor is at least 10mA, permitting output currents to exceed 1A when using high-gain tran- sistors ( > ...
Page 2
... High-Accuracy, Low-Dropout Linear Regulators ABSOLUTE MAXIMUM RATINGS Input Supply Voltage IN to GND ............................................12V Terminal Voltages to GND PFO (MAX687) ........................................-0. PFO (MAX688/MAX689) ......................................-0.3V to 12V All Remaining Pins .....................................-0. PFO Sink Current ...............................................................10mA PFO Source Current (MAX687)...........................................10mA Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied ...
Page 3
... ELECTRICAL CHARACTERISTICS (continued 3.8V, SHDN = V (MAX688/MAX689 noted. Typical values are +25°C.) A PARAMETER SYMBOL MAX687: ON, PFO, SHDN PFO Threshold Voltage Below V - NOM V (Note 5) V NOM PFT PFO Hysteresis Shutdown Threshold Voltage PFT SD Below V PFT Shutdown Threshold Voltage V SD PFO Output Voltage High ...
Page 4
... High-Accuracy, Low-Dropout Linear Regulators __________________________________________Typical Operating Characteristics (Circuits of Figures 1 and 5V FZT749 MAX687 OUTPUT VOLTAGE DISTRIBUTION 3.32289 3.31932 3.31576 3.31219 3.30862 3.30505 3.30149 3.29792 3.29435 3.29078 3.28722 3.28365 0 50 100 150 200 250 NUMBER OF UNITS DROPOUT VOLTAGE vs. LOAD CURRENT ...
Page 5
... 20mA LOAD 3.6V Min 200mA LOAD 100 1k 10k 100k FREQUENCY (Hz) MAX687/MAX688 POWER-UP AND EXIT FROM SHUTDOWN V IN 5V/div V OUT 1V/div SHDN 5V/div 1ms/div I = 500mA LOAD 10nF V OUT 3.3V 10mV/div 500mA I LOAD 200mA/div 0mA ...
Page 6
... The MAX687 is shut down when V OUT (MAX687) and remains latched off until ON is pulsed high. When powered up, the MAX687 does not start up until ON is pulsed high. Connect SHDN is a three-level input that controls the mode of operation. The device is on when V ...
Page 7
... SHDN is raised, the MAX688/MAX689 exit shutdown and enter the standby mode. At the higher SHDN threshold, the output is turned on. Figure 1 shows a typical circuit for the MAX687, and Figure 2 shows the same circuit configured for the MAX688/MAX689. The accuracy of the output current limit depends on accurate knowledge of the PNP pass transistor’ ...
Page 8
... I = 1mA. PFO sources and sinks cur- OUT BASE rent in the MAX687, but is an open drain in the MAX688/MAX689 and only sinks current. When shut down, PFO is always low regardless of the voltage at OUT. Leave PFO open not used. Output Capacitor (C2) ...
Page 9
Information High-Power Output Circuit Figure 3 shows a pseudo-Darlington transistor configu- ration to increase load-current capability and maintain a low dropout voltage with a 4A load. A heatsink must be added when high power is dissipated in the pass ...
Page 10
High-Accuracy, Low-Dropout Linear Regulators Table 2a. Component Suppliers DEVICE MANUFACTURER CAPACITORS 267 series Matsuo F95 Tantalum series Nichicon 595 Tantalum series Sprague OS-CON series low-ESR organic Sanyo semiconductor LXF series United Chemi-Con BIPOLAR TRANSISTORS ZTX749 Zetex T1P42 Motorola 2N4403 Motorola ...
Page 11
Information (continued) PART TEMP. RANGE PIN-PACKAGE MAX688CPA 0°C to +70°C 8 Plastic DIP MAX688CSA 0°C to +70° MAX688CUA 0°C to +70°C 8 µMAX MAX688EPA -40°C to +85°C 8 Plastic DIP MAX688ESA -40°C to +85° MAX689CPA ...
Page 12
High-Accuracy, Low-Dropout Linear Regulators ________________________________________________________Package Information A 0.101mm 0.004 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are Maxim ...