LT1121 Linear Technology Corporation, LT1121 Datasheet
LT1121
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LT1121 Summary of contents
Page 1
... Also the input may be connected to ground or a reverse voltage without reverse current fl ow from output to input. This makes the LT1121 series ideal for backup power situations where the output is held high and the input is at ground or reversed. Under these conditions only 16μ ...
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... GND NC STANDARD S8 PACKAGE. PINS 6 AND 7 CONNECTED TO GROUND SHDN THE A VERSION OF THE LT1121 (S8 ONLY). CONNECTING PINS 6 AND 7 TO THE N8 PACKAGE GROUND PLANE WILL REDUCE THERMAL 8-LEAD PDIP RESISTANCE. SEE THERMAL RESISTANCE S8 PACKAGE TABLES IN THE APPLICATIONS INFORMATION 8-LEAD PLASTIC SO SECTION. ...
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... ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER CONDITIONS Regulated Output Voltage (Note 4) LT1121-3.3 LT1121-5 LT1121 (Note 5) Line Regulation LT1121-3.3 LT1121-5 LT1121 (Note 5) ΔV Load Regulation LT1121-3.3 LT1121-5 LT1121 (Note 5) ΔI Dropout Voltage (Note 6) I LOAD I LOAD I LOAD ...
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... A limited. When operating at maximum output current the input voltage range must be limited. Note 5: The LT1121 (adjustable version) is tested and specifi ed with the adjust pin connected to the output pin. Note 6: Dropout voltage is the minimum input/output voltage required to maintain regulation at the specifi ed output current. In dropout the output ...
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... INPUT VOLTAGE (V) LT1121-5 Output Voltage 5. 1mA OUT 5.06 5.04 5.02 5.00 4.98 4.96 4.94 4.92 125 –50 – TEMPERATURE (°C) LT1121-5 Ground Pin Current 800 T = 25°C J 700 R = 200Ω LOAD I = 25mA* LOAD 600 500 R = 500Ω LOAD 400 I = 10mA* LOAD 300 *FOR OUT 200 ...
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... OUT INPUT VOLTAGE (V) 1121 G13 Ground Pin Current 3.3V (LT1121-3. (LT1121- 3.75V (LT1121) IN DEVICE IS OPERATING IN DROPOUT 125° 25° –55° 100 120 140 160 ...
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... TYPICAL PERFORMANCE CHARACTERISTICS Reverse Output Current (LT1121-5) OUT V = 3.3V (LT1121-3.3) 25 OUT V = 3.8V (LT1121) OUT – –25 100 TEMPERATURE (°C) 1121 G22 Reverse Output Current 100 T = 25° CURRENT FLOWS 80 INTO OUTPUT PIN 70 LT1121 ...
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... LT1121 will act as if there is a diode in series with its input. There will be no reverse current fl ow into the LT1121 and no reverse volt- age will appear at the load. The device will protect both itself and the load. ...
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... In battery backup applications where the output can be held backup battery when the input is pulled to ground, the LT1121 acts like it has a diode in series with its output and prevents reverse current fl ow. Adjustable Operation The adjustable version of the LT1121 has an output voltage range of 3 ...
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... T JMAX THERMAL RESISTANCE JUNCTION TO AMBIENT Output Capacitance and Transient Performance 50ºC/W The LT1121 is designed to be stable with a wide range of 50ºC/W output capacitors. The minimum recommended value is 1μF 58ºC/W with an ESR of 3Ω or less. For applications where space 64ºC/W is very limited, capacitors as low as 0.33μF can be used if 57º ...
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... APPLICATIONS INFORMATION resistor is shown in Table 6. The LT1121 is a micropower device and output transient response will be a function of output capacitance. See the Transient Response curves in the Typical Performance Characteristics. Larger values of output capacitance will decrease the peak deviations and provide improved output transient response. Bypass ...
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... LT1121/LT1121-3.3/LT1121-5 APPLICATIONS INFORMATION When the input of the LT1121 is forced to a voltage below its nominal output voltage and its output is held high, the reverse output current will still follow the curve in Figure 2. This condition can occur if the input of the LT1121 is connected to a discharged (low voltage) battery and the output is held up by either a backup battery second regulator circuit ...
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... NOTE: 1. DIMENSIONS IN 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) LT1121/LT1121-3.3/LT1121-5 N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) (10.160 .255 ± .015* (6.477 ± ...
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... LT1121/LT1121-3.3/LT1121-5 PACKAGE DESCRIPTION .264 – .287 (6.70 – 7.30) .130 – .146 (3.30 – 3.71) .0905 (2.30) BSC .071 (1.80) MAX 14 ST Package 8-Lead Plastic SOT-223 (LTC DWG # 05-08-1630) .248 – .264 (6.30 – 6.71) .114 – .124 (2.90 – 3.15) .059 MAX .033 – .041 (0.84 – 1.04) 10° – 16° ...
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... Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LT1121/LT1121-3.3/LT1121-5 Z Package 8-Lead Plastic TO-92 (Similar to TO-226) (LTC DWG # 05-08-1510) .180 ± ...
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... LT1121/LT1121-3.3/LT1121-5 RELATED PARTS PART NUMBER DESCRIPTION LT1120 125mA Low Dropout Regulator with 20μA I LT1129 700mA Micropower Low Dropout Regulator LT1175 500mA Negative Low Dropout Micropower Regulator LT1521 300mA Low Dropout Micropower Regulator with Shutdown LT1529 3A Low Dropout Regulator with 50μA I LT1611 Inverting 1 ...