MB3828 Fujitsu Microelectronics, Inc., MB3828 Datasheet
MB3828
Related parts for MB3828
MB3828 Summary of contents
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... DC/DC Converter IC MB3828 DESCRIPTION The FUJITSU MB3828 is a pulse width modulation (PWM) DC/DC converter IC chip that provides a selection of 1 3.5 V output voltages for Pentium The MB3828 utilizes synchronous rectification for high efficiency and features a soft-start/discharge control function for ease in designing power supplies in multi-supply systems, making it ideal for Pentium systems ...
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... MB3828 PIN ASSIGNMENT SGND : – ENB : 7 OUT1 : OUT2 : 11 PGND : 12 2 (Top view VREF CSCP 21 : PWRGOOD 20 : VSENSE 19 : CTL 18 : VD4 17 : VD3 16 : VD2 15 : VD1 14 : VD0 (FPT-24P-M03) ...
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... Outputs a “H” level signal when the output voltage is within the range from VTLOW to VTHIGH. 22 CSCP — Timer-latch short-circuit protection capacitor connection pin 23 V — Power supply pin for reference power and control circuit CC 24 VREF O Reference voltage output pin MB3828 Descriptions 3 ...
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... MB3828 BLOCK DIAGRAM VSENSE 20 CS Error Amp. –IN 5 – VD0 D/A 15 VD1 (5-bit) 16 VD2 17 VD3 18 VD4 OSC CT (40 pF) 4 PWRGOOD 21 POWERGOOD PWRGD ( 10%) Overvoltage protection (17.5%) OVP PWM Comp DTC – PWM VB Comp.2 + – + – Comp. SCP Comp. + SCP – ...
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... MB3828 (V) 3.500 3.400 3.300 3.200 3.100 3.000 2.900 2.800 2.700 2.600 2.500 2.400 2.300 2.200 2.100 0 (output OFF) 2.050 2.000 1.950 1.900 1.850 1.800 1.750 1.700 1.650 1.600 1 ...
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... MB3828 ABSOLUTE MAXIMUM RATINGS Parameter Power supply voltage V Bias voltage V Boot voltage V Control input voltage V PWRGOOD output voltage V Output current I O Peak output current I O Allowable dissipation P Storage temperature Tstg * : When mounted cm-square dual-sided epoxy base board WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc ...
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... PWRGOOD pin — Duty 5% –300 (t = 1/f Duty) OSC — 100 — 51 — — — — — — — — — — — –30 MB3828 Value Unit Typ. Max — — — V – 0 — — ...
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... MB3828 ELECTRICAL CHARACTERISTICS Parameter Output voltage Output voltage temperature regulation Reference voltage block Input stability (Ref) Load stability Short circuit output current Threshold voltage Under voltage lockout circuit Hysteresis voltage block (UVLO) Reset voltage Soft start block Charge current (CS) Threshold voltage ...
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... PWRGOOD = 5 V LEAK V 21 PWRGOOD = Discharge control ON IH Discharge control OFF I 7 ENB = 0 V ENB MB3828 ( Value Unit Min. Typ. Max. 1.2 1.3 — V — 1.86 2 — – 1.4 CB – 1.1 — 1 1.4 — ...
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... MB3828 (Continued) Parameter Threshold voltage Over voltage protection Hysteresis voltage comparator block (OVP) VSENSE pin input current D/A input voltage D/A (VD4 to VD0 D/A input voltage pin) (D/A) Input current Standby current General Power supply current 10 Pin Symbol Condition no VSENSE = , 1 — ...
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... Power supply voltage V Reference voltage, CTL pin current vs. Control voltage 5.0 4.0 3.0 2.0 1.0 80.0 100 5.0 10.0 Control voltage V ERR threshold (2.0 V setting) vs. Temperature characteristics 2. 130 k CC 2.02 2.00 1.98 196 1.94 –40.0 –20.0 0.0 Temperature MB3828 8.0 12.0 16.0 20.0 ( +25 C 500 REF 400.0 300.0 I CTL 200.0 100.0 0 15.0 20.0 25.0 (V) CTL 20.0 40.0 60 ...
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... MB3828 ERR threshold (1.3 V setting) vs. Temperature characteristics Error Amp. gain, Phase vs. Frequency characteristics –10 –20 –30 – 100 K Frequency 1. 130 k CC 1.32 1.30 1.28 1.26 1.24 –40.0 –20.0 0.0 20.0 40.0 60.0 Temperature +25 C 180 135 ...
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... Triangular wave oscillator frequency vs. Temperature characteristics 220 210 200 190 180 –40.0 –20.0 Triangular wave oscillator frequency vs. Timing resistance characteristics 1000 100 10 10 Timing resistance ( 130 k CC 0.0 20.0 40.0 60.0 80.0 100.0 Temperature MB3828 100 1000 13 ...
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... MB3828 FUNCTION DESCRIPTION 1. Switching Regulator Function (1) Reference voltage circuit (Ref) The reference voltage circuit uses the voltage supply from the V compensated reference voltage ( 3.5 V) for use as the reference voltage for the internal circuits of the IC chip also possible to supply a reference voltage output external circuits through the VREF pin (pin 24) ...
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... CC Power surges at power-on, or momentary under-voltage situations can cause abnormal operation in the MB3828, which may lead to damage or deterioration in systems. This circuit prevents abnormal operation during times of low voltage by using the supply voltage to detect the level of the internal reference voltage, and fixes output pins OUT1 (pin 8) and OUT2 (pin 11) to “L” level. Once the supply voltage recovers to a level above the threshold voltage of the under voltage lockout circuit, operation is restored ...
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... DC/DC converter. The resulting voltage instability may cause an “L” level from the PWRGOOD block, activating the OVP protection and shutting off the output from the DC/DC converter. To switch VD4 to VD0 pin settings, first input an “L” level control signal to the CTL pin to place the MB3828 in standby status. ...
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... PWRGOOD COMPARATOR CIRCUIT, OVP CIRCUIT OPERATION TIMING CHART CTL signal VD DC/DC VD 0.9 output voltage PWRGOOD signal OUT1 signal OUT2 signal VD 1.175 DC/DC VD 1.1 output voltage VD 0.9 PWRGOOD OUT2 VD 1.175 1.1 Hysteresis voltage 30 mV Hysteresis voltage 30 mV Hysteresis voltage 30 mV MB3828 VD 0.9 Operation when ENB signal is “High”. 17 ...
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... MB3828 CTL LOGIC CIRCUIT OPERATION TIMING CHART CTL signal ENB signal V output voltage REF CS pin voltage DC/DC output voltage DC/DC CONVERTER INPUT VOLTAGE (Vin) AND VB VOLTAGE SETTING The voltage at the CB pin is bootstrapped from the VS pin voltage by an amount equivalent to the VB pin voltage result of the bootstrap capacitance (C ...
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... OUT2 expansion OUT2 OUT2 5 V 100 ns 0 0.2 0.6 0.8 1 Synchronous rectifier length: 200 ns (typ) OUT1 tr: 130 ns (typ) OUT2 tf: 100 ns (typ) MB3828 VD4–VD0 = 00101 (1.8 V) load fosc = 200 kHz setting 500 mV VS OUT1 100 ns 0.4 0.6 0.8 1 ...
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... MB3828 APPLICATION EXAMPLE 20 signals setting voltage Output ...
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... Conversion efficiency vs. Load current characteristics 100 0.01 (Output voltage = 1 Vin = 15 V Vin = 11 V Vin = 22 V Vin = 7 V 0.10 1.00 Load current (A) (Output voltage = 3 Vin = 15 V Vin = 22 V Vin = 11 V Vin = 7 V 0.10 1.00 Load current (A) MB3828 10.00 10.00 (Continued) 21 ...
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... MB3828 V ( CTL ( ( CTL ( Transient response for CTL ON/OFF < Output = 1.8 V, nonload > Transient response for CTL ON/OFF < Output = 3.3 V, nonload > 4700 pF ...
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... 100 Transient response for CTL ON/OFF (Output = 1 200 400 600 Transient response for load abrupt change (Output = 3 200 400 600 0 MB3828 100 s 800 1000 t s 100 s 800 1000 ...
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... Working surfaces, tools and instruments should be properly grounded. • Workers should be grounded by a ground line with 250 resistance in series between the worker and ground. ORDERING INFORMATION Part number MB3828 PFV-G-BND 24 Package 24-pin Plastic SSOP (FPT-24P-M03) Remarks ...
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... NOM "A" +0.10 +0.05 0.22 0.15 –0.05 –0.02 +.004 +.002 .009 .006 –.002 –.001 MB3828 Details of "A" part 0.10±0.10(.004±.004) (STAND OFF) 0 10° 0.50±0.20 (.020±.008) Dimensions in mm (inches) 25 ...
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... MB3828 FUJITSU LIMITED For further information please contact: Japan FUJITSU LIMITED Corporate Global Business Support Division Electronic Devices KAWASAKI PLANT, 4-1-1, Kamikodanaka Nakahara-ku, Kawasaki-shi Kanagawa 211-8588, Japan Tel: 81(44) 754-3763 Fax: 81(44) 754-3329 http://www.fujitsu.co.jp/ North and South America FUJITSU MICROELECTRONICS, INC. Semiconductor Division ...