LTC1558-5 Linear Technology, LTC1558-5 Datasheet
LTC1558-5
Related parts for LTC1558-5
LTC1558-5 Summary of contents
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... LOAD CURRENT LTC1435 3. NORMAL MODE SYNCHRONOUS 30mA AT BACKUP MODE BUCK REGULATOR * SUMIDA CD54- SANYO CADNICA N-110AA † CONSULT LTC1435 DATA SHEET FOR CIRCUIT APPLICATION INFORMATION LTC1558-3.3/LTC1558-5 U fault detector and reset CC Backup Time vs 3.3V Output Load Current 450 3.78V 400 BAK ...
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... PLASTIC SSOP T = 125 C, JMAX T = 125 C, JMAX V = 1.2V unless otherwise noted. BAT A CONDITIONS LTC1558-3.3 LTC1558-5 Boost Converter in Low Current Mode (Note 7) Boost Converter in High Current Mode (Note Voltage at V Relative REF Voltage at V Relative REF ...
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... Note 3: Only applies to 16-pin version. Note 4: Thresholds will track each other and are guaranteed not to overlap. LTC1558-3.3/LTC1558 1.2V unless otherwise noted. BAT A CONDITIONS LTC1558-3.3 LTC1558-5 LTC1558-3.3 LTC1558-5 Fast Recharge I = 1mA CHGT I = 1mA CHGT V Low for < t (Soft Reset) CTL ...
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... NiCd CELL CAPACITY (mAHr) 1558 G02 Trickle Charge Multiplier Factor 10 1.2V BATT 10.0 9.5 9.0 8.5 8.0 7.5 0.05 0 NiCd BATTERY TRICKLE CURRENT (mA) 1558 G05 RESET Output Voltage vs Supply Voltage (LTC1558- 4.7V 4.55V SUPPLY VOLTAGE (V) 1558 G08 Boost Converter Switching Frequency 125 ...
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... The SW, CTL and V pins enter into high impedance states. In shutdown mode, supply current drops to below 50 A and current drawn from the backup cell drops to below greater CC LTC1558-3.3/LTC1558-5 to ground. CC during backup mode. BAK .If ...
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... LTC1558-3.3/LTC1558 PIN FUNCTIONS LOBAT (Pin 9): Low-Battery Detector Output. This is an open-drain output that pulls low when the backup cell drops below 1V. It gives early warning to the system controller that the backup cell is getting weak. This pin is disabled when the LTC1558 is in trickle charge mode. ...
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... REF voltage drops below 1V. RESET is asserted when the cell voltage drops below 0.9V and the LTC1558 enters rises above FB UVLO mode. LTC1558-3.3/LTC1558-5 is greater than FB turns on and EXT BAK BAT 1V 0 ...
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... CC during normal system operations. An LTC1558-3.3 moni- tors a 3.3V supply voltage at its V LTC1558-5 monitors a 5V supply at its V cases, the LTC1558 derives power for the majority of the internal circuitry (except for the boost converter) from the V pin. Table 1 shows the signal conditions for the CC LTC1558’ ...
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... The ripple frequency and output duty cycle is proportional to the inductor discharge time. Given a – 7.5%), fixed inductor value (22 H) and a known peak current REF limit, the booster’s discharge time in each boost cycle is LTC1558-3.3/LTC1558 doubling the available exceeds the (V – 7.5%) boost FB REF – ...
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... LTC1558-3.3/LTC1558 APPLICATIONS INFORMATION proportional to the difference between V and the battery cell voltage, V (1.2V). BAT Assuming ESR = 0 330mA, V IND(PEAK )(R RIPPLE(P-P) IND(PEAK) ESR(CAP) = (330mA)(0 66mV Since V must be scaled down to V BAK resistor ratio = 6V/1.272V = 4.717 Therefore the noise amplitude seen by the FB compara- tors is: = 66mV/4 ...
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... LTC1558 entered UVLO. b) The backup cell was replaced while the main supply was disabled backup cycle was terminated prematurely by a “hard” reset or an output overload. LTC1558-3.3/LTC1558 conditions. This assures that the CC = 5V, the gas CC to the SW pin ...
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... LTC1558-3.3/LTC1558 APPLICATIONS INFORMATION In these cases, the LTC1558 assumes that the backup cell is exhausted and presets the gas gauge counter to a default capacity of 128mAhr. It then initiates a recharge cycle. Setting the gas gauge to this default value results in a fast recharge cycle long enough to replenish 1.6 times 128mAhr of charge into the backup cell (13 ...
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... H will degrade the boost converter’s maxi- mum output power and cause the gas gauge counter to overcharge the backup cell. Table 2 lists the recom- 20ms mended surface mount inductor part numbers. 1558 F05 LTC1558-3.3/LTC1558-5 and SW pins into high impedance BAK in this mode. EXT = 5V. ...
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... LTC1558-3.3/LTC1558 APPLICATIONS INFORMATION Table 2. Recommended Inductors PART TYP INDUCTOR MANUFACTURER NUMBER VALUE Sumida CD54-220 22 H 20% Sumida CDRH73/ 20% Capacitor Selection The LTC1558 requires a minimum V to ensure that the boost converter can regulate the output at 20mA load. The capacitor’s ESR should be small (< 0 minimize voltage spikes that might incorrectly trigger the LTC1558’ ...
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... UVLO during cold power boot or out of backup mode when the LTC1558 is power- ing up the system. A 100k pull-up resistor enables the open-drain BACKUP BAK pin to turn the external P-channel MOSFET off when V is higher than V LTC1558-3.3/LTC1558 C12 1 F ...
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... LTC1558-3.3/LTC1558-5 U TYPICAL APPLICATIONS LTC1558-5 Medium Main Battery Voltage (7V to 18V) Application RESET PUSHBUTTON MAIN BATTERY 7V TO 18V + EXTV 4 SFB 6 V OSENSE 330pF RUN/ 0 OSC OSC 51pF 10k 68pF SGND C1 100pF Typical “Medium Voltage” Application ...
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... U TYPICAL APPLICATIONS LTC1558-5 High Main Battery Voltage (48V) Application R15 100k Q12 2N3906 Z11 12V R16 100k R11 Q11 D1 422k P-CHANNEL 1N4148 1% MTD2955E MAIN R12 BATTERY 100k 48V 1% C1 0.047 3 470pF Typical “High Voltage” Application The maximum main battery voltage is 48V. ...
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... LTC1558-3.3/LTC1558-5 PACKAGE DESCRIPTION 0.007 – 0.0098 (0.178 – 0.249) 0.016 – 0.050 (0.406 – 1.270) * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE ...
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... DWG # 05-08-1610 0.228 – 0.244 (5.791 – 6.197 0.053 – 0.069 (1.346 – 1.752) 0 – 8 TYP 0.014 – 0.019 (0.355 – 0.483) LTC1558-3.3/LTC1558-5 0.189 – 0.197* (4.801 – 5.004 0.150 – 0.157** (3.810 – 3.988 0.004 – ...
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