DEMO MANUAL DC194 MICROPOWER BOOST REGULATOR LT1317/LT1317B Micropower, 600kHz PWM DC/DC Converters U DESCRIPTIO Demonstration Circuit DC194 is a micropower boost result in small, cost effective solutions. The micropower TM regulator that converts an input as low as 1.5V to an output LT1317 shifts automatically to low power Burst Mode of 3.3V or 5.0V. DC194 version A uses the LT 1317CMS8 operation at light loads, whereas the LT1317B operates at version B uses the LT1317BCMS8. This circuit provides a fixed frequency at all loads. Both parts feature a low- regulated power for battery-powered devices, such as battery detector that remains active while the part is shut laptop and palmtop computers, cellular phones, pagers, down. The wide voltage ratings (12V input and 30V LCD panels and other portable devices. It is also useful for switch) make the LT1317 and LT1317B versatile parts, local conversion of logic supplies, such as 3.3V to 5V suitable for implementing boost, flyback and SEPIC conversion in PC card devices. topologies. The LT1317 and LT1317B are 600kHz PWM DC/DC con- , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corportion. verters. Their high operating frequency and small package WWU W PERFOR A CE SU ARY PARAMETER CONDITIONS VALUE Input Voltage (Note 1) V = 3.3V 1.5V to 3.6V OUT V = 5V 1.5V to 5.3V OUT Maximum Load Current, Min V = 3.3V, V = 1.6V 175mA OUT IN V = 3.3V, V = 2.4V 320mA OUT IN V = 5V, V = 2V 140mA OUT IN V = 5V, V = 3.3V 290mA OUT IN Shutdown Current, Typ V = 2.5V, SHDN = 0V 25A IN No Load Quiescent Current, Typ V = 3.3V, V = 2.4V, LT1317 125A OUT IN V = 3.3V, V = 2.4V, LT1317B 4.8mA OUT IN Note 1: This limit is based on the DC194 circuit. The LT1317 can operate from high supply voltages. W U U TYPICAL PERFOR A CE CHARACTERISTICS A D BOARD PHOTO LT1317 Efficiency LT1317 Efficiency Board Photo 90 90 V = 3.3V IN V = 3V IN 80 80 V = 2.4V IN V = 1.6V IN V = 2.4V IN 70 70 V = 1.6V IN 60 60 50 50 LT1317 LT1317 V = 3.3V V = 5V OUT OUT 40 40 0.3 1 10 100 1000 0.3 1 10 100 1000 DC194 BP LOAD CURRENT (mA) LOAD CURRENT (mA) DC194 G04 DC194 G03 1 EFFICIENCY (%) EFFICIENCY (%)DEMO MANUAL DC194 MICROPOWER BOOST REGULATOR TYPICAL PERFORMANCE CHARACTERISTICS LT1317B Efficiency LT1317B Efficiency 90 90 V = 3V V = 3.3V LT1317B IN LT1317B IN V = 3.3V V = 5V OUT OUT 80 80 V = 2.4V IN V = 2.4V IN 70 70 V = 1.6V IN V = 1.6V IN 60 60 50 50 40 40 1 10 100 1000 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) DC194 G06 DC194 G05 Load Current vs Input Voltage Load Current vs Input Voltage 600 600 V = 5V V = 3.3V OUT OUT 500 500 TYPICAL 400 400 TYPICAL MINIMUM 300 300 MINIMUM 200 200 100 100 1.5 2.0 2.5 3.0 3.5 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 INPUT VOLTAGE (V) INPUT VOLTAGE (V) DC194 G01 DC194 G02 PACKAGE A D SCHE ATIC DIAGRA SM TOP VIEW LT1317CMS8 V 1 8 LBO C FB 2 7 LBI LT1317BCMS8 6 V SHDN 3 IN GND 4 5 SW D1 L1 MBR0520LT1 MS8 PACKAGE 10H 8-LEAD PLASTIC MSOP V V OUT IN 6 5 + C1 R6 R7 R4 SW 22F V IN R2 C4 OPT OPT OPT U1 10V 1.00M 0.1F 3 LT1317CMS8(A) SHDN SHDN LTHA + C2 2 7 OR LBI LBI FB 100F LT1317BCMS8(B) 8 6.3V LBO LBO LTHB 3.3V 5V V GND C NOTES: 1 4 1 23 1. FOR VERSION A: USE LT1317CMS8 (LTHA) JP1 R5 2. FOR VERSION B USE LT1317BCMS8 (LTHB) R1A R1B R3 C5 OPT 3. FOR 3.3V OUTPUT, INSTALL SHUNT AT 604k 332k 33k 100pF JP1 PINS 1, 2 3.3V 5V C3 FOR 5V OUTPUT, INSTALL SHUNT AT 3300pF GND JP1 PINS 2, 3 DC194 F01 Figure 1. Demo Board Schematic 2 OUTPUT CURRENT (mA) EFFICIENCY (%) OUTPUT CURRENT (mA) EFFICIENCY (%) W W U UW