 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
AAT2158 Datasheet(PDF) 10 Page - Advanced Analogic Technologies |
|
||||||||||||||||||||||||||||||
AAT2158 Datasheet(HTML) 10 Page - Advanced Analogic Technologies |
|
|
10 / 16 page  AAT2158 1.5A Low Noise Step-Down Converter SwitchRegTM PRODUCT DATASHEET 10 2158.2008.02.1.2 www .analogictech.com junction over-temperature threshold is 140°C with 15°C of hysteresis. Once an over-temperature or over-current fault condition is removed, the output voltage automati- cally recovers. Peak current mode control and optimized internal com- pensation provide high loop bandwidth and excellent response to input voltage and fast load transient events. Soft start eliminates output voltage overshoot when the enable or the input voltage is applied. Under-voltage lockout prevents spurious start-up events. Control Loop The AAT2158 is a peak current mode step-down con- verter. The current through the P-channel MOSFET (high side) is sensed for current loop control, as well as short- circuit and overload protection. A fixed slope compensa- tion signal is added to the sensed current to maintain stability for duty cycles greater than 50%. The peak cur- rent mode loop appears as a voltage-programmed cur- rent source in parallel with the output capacitor. The output of the voltage error amplifier programs the current mode loop for the necessary peak switch current to force a constant output voltage for all load and line conditions. Internal loop compensation terminates the transconductance voltage error amplifier output. The reference voltage is internally set to program the con- verter output voltage greater than or equal to 0.6V. Soft Start/Enable Soft start limits the current surge seen at the input and eliminates output voltage overshoot. When pulled low, the enable input forces the AAT2158 into a low-power, non-switching state. The total input current during shut- down is less than 1μA. Current Limit and Over-Temperature Protection For overload conditions, the peak input current is limit- ed. To minimize power dissipation and stresses under current limit and short-circuit conditions, switching is terminated after entering current limit for a series of pulses. Switching is terminated for seven consecutive clock cycles after a current limit has been sensed for a series of four consecutive clock cycles. Thermal protection completely disables switching when internal dissipation becomes excessive. The junction over-temperature threshold is 140°C with 15°C of hys- teresis. Once an over-temperature or over-current fault conditions is removed, the output voltage automatically recovers. Under-Voltage Lockout Internal bias of all circuits is controlled via the VCC input. Under-voltage lockout (UVLO) guarantees suffi- cient VIN bias and proper operation of all internal cir- cuitry prior to activation. 3.0μH L1 22μF C3 10μF C1 100 R1 0.1μF C2 C1 Murata 10μF 6.3V X5R GRM42-6X5R106K6.3 C3 Murata 22μF 6.3V GRM21BR60J226ME39L X5R 0805 V OUT+ V IN+ L1 Sumida CDRH5D28-3R0NC (see Table 2) R1 and C2 are an optional noise filter for internal VCC. R6, C4, C5-C7 are not populated C8 100pF feed forward LX 14 N/C 6 EN 7 VCC 9 VP 10 N/C 8 LX 13 PGND 3 VP 12 VP 11 FB 4 LX 15 PGND 2 PGND 1 SGND 5 N/C 16 AAT2158 U1 R3 C8 59.0k R4 100K R2 Enable LX GND GND V OUT(V) R3 (k Ω) 0.8 19.6 0.9 29.4 1.0 39.2 1.1 49.9 1.2 59.0 1.3 68.1 1.4 78.7 1.5 88.7 1.8 118 2.0 137 2.5 187 3.3 267 Figure 1: AAT2158 Evaluation Schematic. |
Similar Part No. - AAT2158_08 |
|
Similar Description - AAT2158_08 |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
