LTC1923EUH Linear Technology, LTC1923EUH Datasheet
LTC1923EUH
Specifications of LTC1923EUH
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LTC1923EUH Summary of contents
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... LTC and LT are registered trademarks of Linear Technology Corporation. PLLLPF R T 82k ...
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... Shutdown I DDSHDN DD SHDNTH Shutdown Threshold 2 U (Note 1) FAULT, H/C ................................................. – 0. Operating Temperature Range (Note 2) .. – Storage Temperature Range ................. – 125 C Lead Temperature (Soldering, 10 sec).................. 300 ORDER PART NUMBER PLLLPF R SLEW LTC1923EUH SDSYNC PDRVB CNTRL NDRVB EAOUT AGND PGND NDRVA PDRVA I LIM + CS ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 5V SDSYNC = SLEW DD DD SYMBOL PARAMETER Reference V Reference Output Voltage ...
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LTC1923 ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 5V SDSYNC = SLEW DD DD SYMBOL PARAMETER TEC Voltage Amplifier ATEC ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Oscillator Frequency vs Temperature 265 C = 330pF 10k T 245 225 205 185 165 –50 – 100 130 TEMPERATURE ( C) 1923 G01 ...
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LTC1923 W U TYPICAL PERFOR A CE CHARACTERISTICS Current Limit Threshold vs Temperature 165 160 155 150 145 140 135 130 125 – 130 –20 10 100 TEMPERATURE ( C) 1923 G10 6 System Power Loss vs TEC ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Long-Term Cooling Mode Stability Measured in Environment that Steps 20 Degrees Above Ambient Every Hour. Data Shows Resulting 0.008 C Peak-to-Peak Variation, Indicating Thermal Gain of 2500. 0.0025 C Baseline Tilt Over Plot ...
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LTC1923 CTIO S (GN Package/UH Package) PLLLPF (Pin 1/Pin 30): This pin serves as the lowpass filter for the phase-locked loop when the part is being synchronized. The average voltage on this pin equally alters ...
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CTIO S (GN Package/UH Package) V (Pin 14/Pin 12): Output of the differential TEC voltage TEC amplifier equal to the magnitude of the voltage across the TEC. – TEC (Pin 15/Pin 13): Inverting Input to ...
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LTC1923 CTIO AL DIAGRA 10 W 1923f ...
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U OPERATIO MAIN CONTROL LOOP The LTC1923 uses a constant frequency, voltage mode architecture to control temperature. The relative duty cycles of two pairs of N-/P-channel external MOSFETs, set full-bridge (also referred H-bridge) configuration ...
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LTC1923 U OPERATIO PROTECTION FEATURES Many protection features have been integrated into the LTC1923 to ensure that the TEC is not overstressed or the system does not thermally run away. These features include pulse-by-pulse current limiting, TEC voltage clamp- ing ...
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U OPERATIO V V REF ILIM2 PULLUP I LIM R R ILIM1 LIM3 H/C M1 2N7002 Figure 4. Independently Heating/Cooling Current Limit Transistor M1 is off and the current limit threshold is given by ...
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LTC1923 U OPERATIO pulled to V forcing the gate of M2 low, which allows the DD bridge to operate as described earlier. When a fault occurs and FAULT is asserted low shut off, forcing the gate of M2 ...
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U OPERATIO The terms containing the fixed resistance values are the loading errors introduced by the input impedance of the differential amplifier. A common mode voltage error is also introduced since the addition of R the fully differential nature of ...
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LTC1923 U OPERATIO If the external frequency ( greater than the oscil- PLLIN lator frequency, current is sourced continuously out of the PLLLPF pin. When the external frequency is less than the oscillator frequency, current is sunk by ...
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U U APPLICATIO S I FOR ATIO The thermistor may be isolated from the control circuitry. It has a relatively high input impedance and is therefore susceptible to noise pick up. Extreme care should be taken to ensure this signal ...
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LTC1923 U U APPLICATIO S I FOR ATIO In this application, the bridge supply voltage, oscillator frequency and external filter components determine the amount of ripple current that flows through the TEC. Higher valued filter components reduce the amount of ...
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U U APPLICATIO S I FOR ATIO This voltage error translates back into a temperature setpoint error. Example 10k THRM NTC with 4.4 10k V = 2.5V REF ...
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LTC1923 U U APPLICATIO S I FOR ATIO The linearized thermistor gain around – 25mV/ C. For a minimum loop gain of 5000 as calculated above, the combined gain of the instrumentation and error amplifiers can be ...
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U U APPLICATIO S I FOR ATIO with C on the order of C and note its affect on system A B response. Adjust the values based on observing whether the transient response was improved or not with the goal ...
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LTC1923 U U APPLICATIO S I FOR ATIO Noise and Slew Rate Control One disadvantage of switching regulators is that the switching creates wideband harmonic energy. The high frequency content can pose problems to associated cir- cuitry. To combat this ...
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U U APPLICATIO S I FOR ATIO the total gate charges of the NMOS and PMOS on one side of the bridge, and f is the oscillator frequency. The factor of 2 arises from there being two sets of MOSFETs ...
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LTC1923 U U APPLICATIO S I FOR ATIO Higher Voltage Applications A bank of TECs can be wired in series to minimize board real estate utilized by the application. A higher voltage supply may be required depending upon how many ...
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U U APPLICATIO S I FOR ATIO PLLLPF SLEW T SDSYNCB V REF CNTRL PDRVB EAOUT NDRVB AGND PGND LTC1923 SS NDRVA I PDRVA LIM + V CS SET – FAULT CS V ...
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LTC1923 U TYPICAL APPLICATIO 26 1923f ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Peak Output Current, 1G Electrical Isolation, SO-8 Package Max Gain Error 0.01%, Input Offset Drift of 50nV/ C, Input Offset Voltage www.linear.com BOTTOM VIEW—EXPOSED PAD R = 0.115 0.40 0.10 TYP (UH) QFN 0102 0.23 0.05 0.50 BSC = 270 A, CC 1923f LT/TP 0502 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2001 ...