cs51221 ON Semiconductor, cs51221 Datasheet
cs51221
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cs51221 Summary of contents
Page 1
... In addition, this device includes such features as: Soft−Start, accurate duty cycle limit control, less than 50mA startup current, over and undervoltage protection, and bidirectional synchronization. The CS51221 is available lead SOIC narrow surface mount package. Features • ...
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... CS51221 CS51221 Figure 1. Application Diagram, 36 V− 5.0 V/5.0 A Converter http://onsemi.com 2 ...
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... T T Characteristic Start/Stop Voltages Start Threshold Stop Threshold Hysteresis I @ Startup CC Supply Current I Operating CC I Operating C I Operating C CS51221 Rating Reflow: (SMD styles only) (Note MAX MIN 15 V −0.3 V 1.0 A Peak, 200 mA DC 6.0 V −0 6.0 V −0 6.0 V −0.3 V 6.0 V − ...
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... Discharge Current Synchronization Input Threshold Output Pulse Width Output High Voltage Input Resistance SYNC to Drive Delay Output Drive Current 2. Guaranteed by design, not 100% tested in production. CS51221 < 85°C; −40°C < T < 125°C; 3.0 V < Test Conditions 0 mA < I < 2.0 mA REF − ...
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... Soft−Start Fault Voltage Blanking Blanking Time SS Blanking Disable Threshold COMP Blanking Disable Threshold Thermal Shutdown Thermal Shutdown Thermal Hysteresis 3. Guaranteed by design, not 100% tested in production. CS51221 < 85°C; −40°C < T < 125°C; 3.0 V < Test Conditions V − GATE ...
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... V reference voltage output. Decoupling capacitor can be selected from 0. mF REF 14 V Logic supply voltage PGND Output power stage ground Output power stage supply voltage. C CS51221 Function and capacitor C determine oscillator frequency and maximum duty cycle http://onsemi.com 6 . MAX ...
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... 2 1.0 V Trip Points V 3 (1.263 V) − EAMP − COMP Soft−Start Clamp FF I SET DISABLE 150 ns Blank I SENSE CS51221 3 3.3 V REF − V REF + 3.1 V OSC G2 Max Duty Cycle (Sat Sense 1.8 V Max + PWM Comp − + − FF Discharge G3 Max SS 3.0 V Det + − ...
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... During power−down, the UVL CC comparator allows the controller to operate until the V stop threshold is reached. The CS51221 requires only 50 mA during startup. The output stage is held at a low impedance state in lock out mode. During power up and fault conditions, the Soft−Start clamps the Comp pin voltage and limits the duty cycle ...
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... However, the low pass filter will inevitably change the shape of the current pulse and also add cost. The CS51221 uses leading edge blanking circuitry that blocks out the first 150 ns (typ) of each current pulse. This removes the leading edge spikes without altering the current waveform. The blanking is disabled during Soft− ...
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... When the R the 0.95 V (typ) Valley Clamp Voltage, the clamp is disconnected after a brief delay and CS51221 Switch Frequency and Maximum Duty Cycle Calculations Oscillator timing capacitor, C through R T During the discharge time, the internal clock signal sets the Gate output to the low state, thus providing a user selectable maximum duty cycle clamp ...
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... In Figure 13, the voltage divider uses three resistors in series to set OV and UV threshold seen from the input voltage. The values of the resistors can be calculated from the following three equations, where the third equation is derived from OV hysteresis requirement IN(LOW IN(HIGH CS51221 1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 0.55 ...
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... G K −T− SEATING PLANE 0.25 (0.010 PACKAGE THERMAL DATA Parameter R qJC R qJA CS51221 PACKAGE DIMENSIONS SOIC−16 D SUFFIX CASE 751B−05 ISSUE J −B− 0.25 (0.010 SOIC−16 Typical ...
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... L PIN 1 IDENT. 1 0.15 (0.006 −V− C 0.10 (0.004) −T− SEATING PLANE D CS51221 PACKAGE DIMENSIONS TSSOP−16 CASE 948F−01 ISSUE Ç Ç Ç É É −U− J1 Ç Ç Ç É É ...
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... USA/Canada Japan: ON Semiconductor, Japan Customer Focus Center 2−9−1 Kamimeguro, Meguro−ku, Tokyo, Japan 153−0051 Phone: 81−3−5773−3850 http://onsemi.com 14 ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. CS51221D ...