isl8540 Intersil Corporation, isl8540 Datasheet
isl8540
Available stocks
Related parts for isl8540
isl8540 Summary of contents
Page 1
... MARKING (°C) ISL8540IVEZ ISL8540IVEZ - HTSSOP MDP0048 ISL8540IVEZ-T* ISL8540IVEZ - HTSSOP MDP0048 *Please refer to TB347 for details on reel specifications. NOTE: These Intersil Pb-free plastic packaged products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate PLUS ANNEAL - e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations ...
Page 2
... OSCILLATOR Total Variation on Set Frequency Frequency Range (Set by RTCT) SYNC Range Oscillation Frequency 2 ISL8540 Thermal Information Thermal Resistance (Typical, Notes 1, 2) θ HTSSOP Package . . . . . . . . . . . . . . . . Maximum Power Dissipation Maximum Junction Temperature (Hermetic Package or Die +150°C Maximum Junction Temperature (Plastic Package +150°C Maximum Storage Temperature Range . . . . . . . . . .-65° ...
Page 3
... Input LOW Level (Unasserted) Input Current HIGH Input Current LOW SYNC Input HIGH Level (Asserted) Input LOW Level (Unasserted) Input Current HIGH Input Current LOW THERMAL SHUT-DOWN Thermal Shut-down Temperature Thermal Shut-down Hysteresis 3 ISL8540 = 24V 5.0V OUT OUT SYMBOL TEST CONDITIONS Δ OSC ...
Page 4
... There are no duty cycle restrictions on the input sync signal. Input thresholds are TTL compatible. 4 ISL8540 RTCT (Pin 9) A resistor to VIN and a capacitor to GND determine the frequency of the saw-tooth oscillator. Resistor range 20k to 100k. Capacitor range 470pF to 1.2nF. The oscillator amplitude will vary from approximately 0 ...
Page 5
... FB 3pF 1.6k +14 -14% 5 ISL8540 RTCT RAM EAM OVFLT UVFLT FIGURE 1. BLOCK DIAGRAM OF THE ISL8540 SYNC VCC5 LDO PW M LOG IC CONTRO LLER PRO TECTIO N DRIVER O CFLT + + CSA 3µs DELAY September 18, 2007 VIN ...
Page 6
... VIN 9V TO 40V VIN + 150µF 0.1µF LX PGND BOOT EN# VIN VCC5 R1 20k SYNC C3 C1 1µF RTCT 470pF SGND FIGURE 2. TYPICAL SCHEMATIC FOR ISL8540 (5V V VIN VIN 18V TO 40V VIN + 150µF 0.1µF LX PGND BOOT EN# VIN VCC5 R1 20k SYNC C3 1µF C1 RTCT ...
Page 7
... FIGURE 6. EFFICIENCY vs LOAD (36V INPUT - 500kHz) 5.10 5.05 5.00 12V V IN 4.95 4.90 36V V 4.85 4.80 0.0 0.5 1.0 1.5 OUTPUT LOAD (A) FIGURE 8. V REGULATION vs LOAD OUT ( 500kHz) OUT 7 ISL8540 Circuit of Figure 24V, EN 500KHz Typical values are +25°C. A 100 5V V OUT OUT 1.2V V OUT 1.5 2.0 ...
Page 8
... OUT 24.75 24. OUT 24.25 24.00 23.75 23. OUT 23. INPUT VOLTAGE (V) FIGURE 14. OUTPUT VOLTAGE REGULATION 500kHz) OUT 8 ISL8540 Circuit of Figure 24V, EN 500KHz Typical values are +25°C. (Continued) A 3.4 3.4 36V V IN 3.3 3.3 3.3 3.2 3.2 1.5 2.0 FIGURE 11. OUTPUT VOLTAGE REGULATION vs V 12.3 12.2 12 12.0 11.9 11.8 11.7 30 ...
Page 9
... OUTPUT LOAD (A) FIGURE 18. POWER DISSIPATION vs LOAD (V = 24V - 500kHz) OUT LX = 10V/DIV V RIPPLE = 50mV/DIV OUT RTCT = 2V/DIV FIGURE 20. STEADY STATE OPERATION WITH FULL LOAD 9 ISL8540 Circuit of Figure 24V, EN 500KHz Typical values are +25°C. (Continued) A 3.0 2.5 36V V IN 2.0 1.5 1.0 24V V IN 0.5 0.0 1.5 2.0 FIGURE 17. POWER DISSIPATION vs LOAD ...
Page 10
... Typical Performance Curves FIGURE 22. SOFT-START AT NO LOAD FIGURE 24. SOFT-START AT FULL LOAD 10 ISL8540 Circuit of Figure 24V, EN 500KHz Typical values are +25°C. (Continued 5V/DIV V = 2V/DIV OUT PRE-BIASED WITH 2V/DIV IL = 0.5A/DIV FIGURE 23. SOFT-START WITH PRE-BIASED EN = 5V/DIV V = 2V/DIV OUT ...
Page 11
... Start-Up and Shut-Down When the EN# pin is connected to a logic high, the ISL8540 is in the shut-down mode. All the control circuitry and both MOSFETs are off, and V falls to zero. In this mode, the OUT total input current is less than 110µ ...
Page 12
... At the end of the fourth soft-start wait period, the fault counters are reset and soft-start is attempted again. Thermal Protection If the ISL8540 IC junction temperature reaches a nominal temperature of +150°C, the regulator will be disabled. The ISL8540 will not re-enable the regulator until the junction temperature drops below +135° ...
Page 13
... Given a sufficiently fast control loop design, the ISL8540 will provide either 0% or 100% duty cycle in response to a load transient. The response time is the time required to slew the inductor current from an initial current value to the transient current level ...
Page 14
... LC = ------------------------------------------ - f ESR = 2π The compensation network consists of the transconductance amplifier (internal to the ISL8540) and the impedance networks Z and Z . The goal of the compensation IN FB network is to provide a closed loop transfer function with the highest 0dB crossing frequency (f 0dB margin ...
Page 15
... Careful component selection, tight layout of the critical components, and short, wide traces minimizes the magnitude of voltage spikes. There are two sets of critical components in the ISL8540 switching converter. The switching components are the most critical because they switch large amounts of energy, and therefore tend to generate large amounts of noise ...
Page 16
... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 16 ISL8540 MDP0048 A HTSSOP (HEAT-SINK TSSOP) FAMILY SYMBOL PIN #1 I ...