ltc3100 Linear Technology Corporation, ltc3100 Datasheet
ltc3100
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ltc3100 Summary of contents
Page 1
... LDO regulator. The LTC3100 features a wide input voltage range of 0.65V to 5V. The step-down converter can be powered by the output of the step-up converter or from a separate power source between 1 ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3100EUD#PBF LTC3100EUD#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... Measured on V (Note 4), RUNBST = 0V INBK Measured FBBK = 620mV, MODE = OPEN, INBK RUNBST = SWBK = 5V INBK SWBK = 0V INBK V = 3.3V INBK V = 3.3V INBK FBBK < 590mV FBBK > 610mV LTC3100 l The denotes the specifi cations = 1.2V 3.3V, INBST BST MIN TYP MAX 0.3 0.4 l 700 850 ...
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... LTC3100 ELECTRICAL CHARACTERISTICS: STEP-DOWN CONVERTER specifi cations which apply over the full operating temperature range. Extended commercial grade: –40°C to 85° 25°C, unless otherwise noted. A PARAMETER RUNBK Input High Voltage RUNBK Input Low Voltage RUNBK Input Current Soft-Start Time ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3100E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: Specifi ...
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... LTC3100 TYPICAL PERFORMANCE CHARACTERISTICS Step-Up DC/DC Converter No-Load Input Current Mode = Open, LDO and Buck Off 300 250 200 150 100 OUT 3.3V OUT V = 1.8V OUT 0 1 1.5 2 2 (V) INBST 3100 G05 Burst Mode Threshold Current 3.3μ 3.3V OUT ...
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... OUT 100 1000 FREQUENCY (Hz) 50mA/DIV VLDO 100mV/DIV 3100 G17 5μs/DIV LTC3100 T = 25°C, unless otherwise specifi ed. A Load Step Response, 5mA-100mA Burst Mode Operation Enabled 10μF BST OUT 3100 G13 100μs/DIV Soft-Start Time LDO C = 2.2μ ...
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... LTC3100 TYPICAL PERFORMANCE CHARACTERISTICS Step-Down DC/DC Converter Effi ciency vs Load Current and V for V = 1.2V O 100 0.01 0.1 1 LOAD CURRENT (mA) No-Load Input Current vs V (Mode = Open) INBK 1.5 2 2.5 3 3.5 4 4.5 V (V) INBK 3100 G21 Output Voltage Ripple in Fixed Frequency and Burst Mode Operation C = 10μ ...
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... The output voltage can be adjusted from 0.6V to 5.5V by: V OUT BUCK _ RUNLDO (Pin 10): Logic-Controlled Shutdown Input for the LDO Regulator. There is an internal 4MΩ pull-down on this pin. RUNLDO = High: Normal operation RUNLDO = Low: Shutdown LTC3100 T = 25°C, unless otherwise specifi ed BUCK BOOST LDO 1 ...
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... LTC3100 PIN FUNCTIONS FBLDO (Pin 11): Feedback Input to the g for the LDO Regulator. Connect the resistor divider tap to this pin. The output voltage can be adjusted from 0.6V to 5.25V by: ⎛ 600 . V • ⎝ ⎜ 1 OUT LDO FBBST (Pin 12): Feedback Input to the g for the Boost Converter ...
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... AMPLIFIER/ I ZERO SLEEP COMPARATOR FB – MODE + CONTROL 1.2V BURST CLAMP I PK SOFT-START COMPARATOR WAKE UVLO CLK SHUTDOWN I TSD COMPARATOR LOGIC COMPARATOR PAD GND 7 PGND LTC3100 V BOOST BST FBBST 12 PGBST 15 – + 1.1V WELL SWITCH V LDO 0.15Ω 3 100mA ERROR AMPLIFIER FBLDO I LIM – – 0.6V RUNLDO ...
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... With separate power inputs for the boost and buck con- verters, along with independent enable and power good functions, the LTC3100 is very fl exible. The two converters can operate from the same input supply, or from two dif- ferent sources, or can even be cascaded by powering the buck converter from the output of the boost converter ...
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... This is ac- complished internally on the LTC3100 through the addition of a compensating ramp to the current sense signal. The LTC3100 performs current limiting prior to addition of the slope compensation ramp and therefore achieves a peak inductor current limit that is independent of duty cycle. ...
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... The buck converter uses the same 1.5MHz oscillator used by the boost converter. PWM Mode Operation When the MODE pin is held low, the LTC3100 buck converter uses a constant-frequency, current mode control architec- ture. Both the main (P-channel MOSFET) and synchronous rectifi ...
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... Error Amplifi er and Compensation The LTC3100 buck converter utilizes an internal transcon- ductance error amplifi er. Compensation of the feedback loop is performed internally to reduce the size of the application circuit and simplify the design process. The ...
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... LTC3100 OPERATION LDO REGULATOR OPERATION The LDO regulator utilizes an internal 1.3Ω (typical) P-channel MOSFET pass device to supply up to 100mA of load current with a typical dropout voltage of 130mV. The input voltage to the LDO is internally connected to the boost output (V pin), and can share the same fi lter BST capacitor ...
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... APPLICATIONS INFORMATION PC Board Layout Guidelines The LTC3100 switches large currents at high frequen- cies. Special care should be given to the PC board layout to ensure stable, noise-free operation. You will not get advertised performance with a careless layout. Figure 1 depicts the recommended PC board layout. A large ground pin copper area will help to lower the chip temperature ...
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... Molded chokes and some chip inductors usually do not have enough core area to support the peak induc- tor currents of 800mA seen on the LTC3100. To minimize radiated noise, use a shielded inductor. See Table 1 for suggested components and suppliers. ...
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... Table 3.Buck Minimum Inductance OUTPUT VOLTAGE 0.6V 0.8V 1.2V 2V 2.7V 3.3V Larger values of inductor will also provide slightly greater output current capability before reaching current limit (by reducing the peak-to-peak ripple current). LTC3100 ⎞ − OUT μ ⎠ ⎟ 100mA which ...
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... LTC3100 APPLICATIONS INFORMATION Table 4. Recommended Buck Inductors VENDOR Coilcraft LPS3008, LPS3010, LPS3015 (847) 639-6400 www.coilcraft.com Coiltronics SD3114, SD3118, SD3112 FDK MIPF2016 MIPF2520, MIPS2520 Murata LQH32C www.murata.com LQM31P Sumida CDRH2D11, CDRH2D09 (847) 956-0666 CMD4D06-4R7MC www.sumida.com CMD4D06-3R3MC Taiyo-Yuden NR3010, NR3012 www.t-yuden.com TDK VLF3010, VLF3012 www ...
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... 0.9V 25.5k L2 BATT 220mA 1.2V 3.3μH BATT 4 V_CORE = 1. 10μ BOOST_GOOD BUCK_GOOD LTC3100 ⎛ ⎞ 600 . V • ⎝ ⎜ 1 ⎠ ⎟ Output Voltages During Soft-Start for Sequenced Converter 3100 TA02b 1ms/DIV V , 1V/DIV BST V , 1V/DIV I/O V ...
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... Single-Cell/Two-Cell or USB Input to 3.3V/1.8V Converter MBR0520 USB INPUT C1 L1 4.7μF 3.3μ BATT 0.9V TO SWBST V V INBK BST 3. FBBST INBST C4 4.7μF V LDO LTC3100 FBLDO 13 MODE SWBK 14 RUNBST FBBK R7 10 64.9k RUNLDO PGBST 8 PGBK RUNBK GND R4 7 20k 22 +5V AT 200mA V BOOST 4.7μF ...
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... Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0.05 3.00 ± 0.10 (4 SIDES) 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC3100 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.25 × 45° CHAMFER TYP 15 16 0.40 ± 0. (UD16) QFN 0904 0.25 ± 0.05 0.50 BSC ...
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... TYPICAL APPLICATION Single-Cell to 1.2V/1.8V Converter L1 3.3μ BATT SWBST V V INBK BST 0. INBST FBBST 2.2μ LDO LTC3100 11 FBLDO 13 MODE 4 14 SWBK OFF ON RUNBST 9 10 FBBK RUNLDO 15 PGBST 8 6 RUNBK GND PGBK 7 3100 TA05a RELATED PARTS PART NUMBER DESCRIPTION LTC3442 1 ...