ver: 0.5 jul 23, 2009 tel: 886-3-5788833 http://www.gmt.com.tw 1 G5699 global mixed-mode technology inc. dual 1.4mhz, 1a synchronous step-down regulator features ? high efficiency: up to 95% ? internal soft start function ? output current channel 1: 1a channel 2: 1a ? 2.7v to 5.5v input voltage range ? 1.4mhz switching frequency ? no schottky diode required ? 100% duty cycle in dropout operation ? 0.6v reference allows low output voltages ? <1 a shutdown current ? current mode operation for excellent line and load transient response ? over temperature protected ? rohs compliant applications ? cellular telephones ? personal information appliances ? microprocessors and dsp core supplies ? wireless and dsl modems ? digital still and video cameras ? mp3 players ? portable instruments general description the G5699 is a dual channel high efficiency monolithic synchronous buck regulator using a constant fre- quency, current mode architecture. supply current during operation is only 50 a and drops to <1 a in shutdown for each channel. the 2.7v to 5.5v input voltage range makes the G5699 ideally suited for sin- gle li-ion battery-powered applications. both regula- tors have independent input and enable pins. 100% duty cycle provides low dropout operation, extending battery run time in portable systems. switching fre- quency is internally set at 1.4mhz, allowing the use of small surface mount inductors and capacitors. the internal synchronous switch increase efficiency and eliminates the need for an external schottky diode. built-in soft start function eliminates in-rush current that could damage the system. the G5699 is available in tdfn3x3-12 package. ordering information order number marking temp. range package (green) G5699rq1u 5699 -40 c~ +85 c tdfn3x3-12 note: rq: tdfn3x3-12 1: bonding code u: tape & reel pin configuration typical application circuit G5699 tdfn3x3-12 g5625 lx2 vin2 fb1 gnd nc2 en2 G5699 v out1 = 0.6v ? (1+ ) r1 r2 1 2 3 4 12 11 10 5 thermal pad gnd fb2 6 7 8 9 nc1 en1 lx1 vin1 vin1 lx1 en1 fb1 c in1 4.7 f cer v in1 2.2 h c out1 4.7 f cer v out1 c fb1 * (option) r1 r2 vin2 lx2 en2 fb2 c in2 4.7 f cer v in2 2.2 h c out2 4.7 f cer v out2 c fb2 * (option) r3 r4 v out2 = 0.6v ? (1+ ) r3 r4 * refer to table. 1 for component selection note: recommend connecting the thermal pad to the ground for excellent power dissipation. G5699 tdfn3x3-12 g5625 lx2 vin2 fb1 gnd nc2 en2 G5699 v out1 = 0.6v ? (1+ ) r1 r2 1 2 3 4 12 11 10 5 thermal pad gnd fb2 6 7 8 9 nc1 en1 lx1 vin1 vin1 lx1 en1 fb1 c in1 4.7 f cer v in1 2.2 h c out1 4.7 f cer v out1 c fb1 * (option) r1 r2 vin2 lx2 en2 fb2 c in2 4.7 f cer v in2 2.2 h c out2 4.7 f cer v out2 c fb2 * (option) r3 r4 v out2 = 0.6v ? (1+ ) r3 r4 * refer to table. 1 for component selection G5699 tdfn3x3-12 g5625 lx2 vin2 fb1 gnd nc2 en2 G5699 v out1 = 0.6v ? (1+ ) r1 r2 v out1 = 0.6v ? (1+ ) r1 r2 1 2 3 4 12 11 10 5 thermal pad gnd fb2 6 7 8 9 nc1 en1 lx1 vin1 vin1 lx1 en1 fb1 c in1 4.7 f cer v in1 2.2 h c out1 4.7 f cer v out1 c fb1 * (option) r1 r2 vin2 lx2 en2 fb2 c in2 4.7 f cer v in2 2.2 h c out2 4.7 f cer v out2 c fb2 * (option) r3 r4 v out2 = 0.6v ? (1+ ) r3 r4 * refer to table. 1 for component selection note: recommend connecting the thermal pad to the ground for excellent power dissipation.
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