LM26003QMH/NOPB National Semiconductor, LM26003QMH/NOPB Datasheet
LM26003QMH/NOPB
Specifications of LM26003QMH/NOPB
Available stocks
Related parts for LM26003QMH/NOPB
LM26003QMH/NOPB Summary of contents
Page 1
... Other features include Power good, adjustable soft-start, en- able pin, input under-voltage protection, and an internal boot- strap diode for reduced component count. Typical Application Circuit © 2010 National Semiconductor Corporation LM26003/LM26003Q Features ■ LM26003Q is an Automotive Grade product that is AEC- Q100 grade 1 qualified (-40°C to +125°C operating junction temperature) ■ ...
Page 2
Connection Diagram Ordering Information Order Number Package Type LM26003MH TSSOP-20EXP LM26003MHX LM26003QMH TSSOP-20EXP LM26003QMHX *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies. Reliability qualification is compliant with the requirements and ...
Page 3
Pin # Pin Name Description 16 VDD The output of the internal regulator. Bypass with a minimum 1.0 µF capacitor. 17 BOOT Bootstrap capacitor pin. Connect a 0.1 µF minimum ceramic capacitor from this pin generate the ...
Page 4
... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Voltages from the indicated pins to GND: VIN SW (Note 7) VDD VBIAS FB BOOT PGOOD FREQ SYNC Electrical Characteristics over the junction temperature (T ) range of -40°C to +125°C. Unless otherwise stated, Vin = 12V. Minimum and Maximum limits J are guaranteed through test, design, or statistical correlation ...
Page 5
Symbol Parameter T Minimum Off-time OFFMIN T Minimum On-time ONMIN TH Sleep Mode Threshold Hysteresis SLEEP_HYS TH Wake Up Threshold WAKE I BOOT Pin Leakage Current BOOT Protection I Peak Current Limit LIMPK V Short Circuit Frequency Foldback FB_SC Threshold ...
Page 6
Typical Performance Characteristics 12V 25°C. J Efficiency vs Load Current (300 kHz) VFB vs Temperature IQ and IVBIAS vs Temperature (Sleep Mode) www.national.com Unless otherwise specified the following conditions apply: Vin = Efficiency vs Load Current (500 kHz) ...
Page 7
Startup Waveforms 30067647 Load Transient Response 30067646 UVLO Threshold vs Temperature (VDD = VIN) Peak Current Limit vs Temperature Normalized Switching Frequency vs Temperature (300kHz) 30067645 7 30067641 30067643 www.national.com ...
Page 8
Block Diagram www.national.com 8 30067603 ...
Page 9
Operation Description GENERAL The LM26003 is a current mode PWM buck regulator. At the beginning of each clock cycle, the internal high-side switch turns on, allowing current to ramp-up in the inductor. The in- ductor current is internally monitored during ...
Page 10
Iin = Dwake Where I is the gate drive current, calculated as ...
Page 11
During high over-current conditions, such as output short cir- cuit, the LM26003 employs frequency foldback as a second level of protection. If the feedback voltage falls below the short circuit threshold of 0.9V, operating frequency is reduced, thereby reducing average ...
Page 12
FIGURE 6. Off-Pulse Skipping Waveforms Vin = 3.5V, Vnom = 3.3V, fnom = 305 kHz UVLO is sensed at both VIN and VDD, and is activated when either voltage falls below 2.96V (typical). Although VDD is typically less than 200 ...
Page 13
Design Information EXAMPLE CIRCUIT Figure 7 shows a complete typical application schematic. The components have been selected based on the design criteria given in the following sections. SETTING OUTPUT VOLTAGE The output voltage is set by the ratio of a ...
Page 14
Where Re is the ESR of the output capacitors, and Vrip is a peak-to-peak value. This equation assumes that the output capacitors have some amount of ESR. It does not apply to ceramic output capacitors. If this method is used, ...
Page 15
Also keep in mind that the reverse leakage current of a Schottky diode increases with temperature and with reverse voltage. Reverse voltage equals roughly the in- put voltage in a buck converter. At hot, the diode reverse leakage ...
Page 16
Once the fp range is determined, R5 should be calculated using: Where B is the desired feedback gain in v/v between fp and fz, and gm is the transconductance of the error amplifier. A gain value around 10 dB ...
Page 17
GND pin must be connected to ground. This quieter plane should be connected to the high current ground plane at a quiet location, preferably near the Vout ground as shown by the dashed line in Figure 11. The EP GND ...
Page 18
Physical Dimensions www.national.com inches (millimeters) unless otherwise noted eTSSOP-20 Package 20-Lead Exposed Pad TSSOP Package NS Package Number MXA20A 18 ...
Page 19
Notes 19 www.national.com ...
Page 20
... For more National Semiconductor product information and proven design tools, visit the following Web sites at: www.national.com Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www ...