KA7500C. SMPS Controller. Features. Description. Internal Block Diagram.

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Rev. 1.0.1

Features

• Internal Regulator Provides a Stable 5V Reference Supply Trimmed to ±1% Accuracy.

• Uncommitted Output TR for 200mA Sink or Source Current

• Output Control for Push-Pull or Single-Ended Operation • Variable Duty Cycle by Dead Time Control (Pin 4)

Complete PWM Control Circuit

• On-Chip Oscillator With Master or Slave Operation • Internal Circuit Prohibits Double Pulse at Either Output

Description

The KA7500C is used for the control circuit of the pulse width modulation switching regulator. The KA7500C consists of 5V reference voltage circuit, two error amplifiers, flip flop, an output control circuit, a PWM comparator, a dead time comparator and an oscillator. This device can be operated in the switching frequency of 1kHz to 300kHz. The precision of voltage reference (Vref) is improved up to ±1% with trimming. This provides a better output voltage regulation. The operating temperature range is -25°C ~ +85°C.

16-DIP

16-SOP 1

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Internal Block Diagram

OSCILLATOR 6 5 4 1 2 16 15 3 7 14 12 10 11 9 8 13 BAND GAP REFERENCE 1 2 + _ + _ 0.7MA D CK Q Q C1 E1 C2 E2 VCC VREF GND COMP INPUT OUTPUT CONTROL 5V RT CT DEAD TIME CONTROL EA(+) EA(-) EA(+) EA(-) 1.2V PWM COMP

KA7500C

SMPS Controller

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Absolute Maximum Ratings

Recommended Operating Conditions

Parameter Symbol Value Unit

Supply Voltage VCC 42 V

Collector Supply Voltage VC 42 V

Output Current IO 250 mA

Amplifier Input Voltage VIN VCC +0.3 V

Power Dissipation (TA = 25°C) PD _{0.9 (KA7500CD)}1 (KA7500C) W

Operating Temperature Range TOPR -25 ~ +85 °C

Storage Temperature Range TSTG -65 ~ +150 °C

Junction Temperature Tj 125 °C

Parameter Symbol Min. Typ. Max. Unit

Power Supply Voltage VCC 7.0 15 40 V

Collector Output Voltage VC1,VC2 - 30 40 V

Collector Output Current (Each Transistor) IC1,IC2 - - 200 mA

Amplifier Input Voltage VIN 0.3 - VCC-2.0 V

Current Into Feedback Terminal Ifb - - 0.3 mA

Reference Output Current Iref - - 10 mA

Timing Resistor RT 1.8 30 500 ΚΩ

Timing Capacitor CT 0.0047 0.001 10 uF

Oscillator Frequency fosc 1.0 40 200 kHz

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Electrical Characteristics

(VCC = 20V, f = 10kHz, TA = -25°C to +85°C, unless otherwise specified)

Parameter Symbol Conditions Min. Typ. Max. Unit

REFERENCE SECTION

Reference Output Voltage VREF

IREF = 1mA, TA=25°C(Note1) 4.95 5.0 5.05

V

IREF = 1mA 4.9 5.0 5.1

Line Regulation RLine VCC = 7V to 40V - 2.0 25 mV

Load Regulation RLOAD IREF = 1mA to 10mA - 1.0 15 mV Short Circuit Output Current ISC VREF = 0V 10 35 50 mA

OSCILLATOR SECTION

Oscillation Frequency fosc

CT = 0.001µF, RT = 30KΩ - 40

-kHz CT = 0.001µF, RT = 12KΩ,TA=25°C 9.2 10 10.8

CT = 0.001µF, RT = 30KΩ,

TA=Tlow to Thigh 9.0 - 12

Frequency Change with

Temperature ∆f/∆T CT = 0.01µF, RT = 12KΩ - - 2 %

DEAD TIME CONTROL SECTION

Input Bias Current IBIAS VCC = 15V, 0V ≤ V4 ≤ 5.25V - -2.0 -10 µA Maximum Duty Cycle D(MAX) V_{O.C Pin = V}CC = 15V, V4 = 0V

REF 45 - - %

Input Threshold Voltage VITH

Zero Duty Cycle - 3.0 3.3

V

Max. Duty Cycle 0 -

-ERROR AMP SECTION

Input Offset Voltage VIO V3 = 2.5V - 2.0 10 mV

Input Offset Current IIO V3 = 2.5V - 25 250 mA

Input Bias Current IBIAS V3 = 2.5V - 0.2 1.0 µA

Common Mode Input Voltage VCM 7V ≤ VCC ≤ 40V -0.3 - VCC V Open-Loop Voltage Gain GVO 0.5V ≤ V3 ≤ 3 .5V 70 95 - dB

Unit-Gain Bandwidth BW - - 650 - kHz

PWM COMPARATOR SECTION

Input Threshold Voltage VITH Zero Duty Cycle - 4 4.5 V

Input Sink Current ISINK V3 = 0.7V -0.3 -0.7 - mA

OUTPUT SECTION

Output Saturation Voltage

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Electrical Characteristics

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(VCC = 20V, f = 10kHz, TA = -25°C to +85°C, unless otherwise specified)

Note :

1. This is guaranteed where the marking code of the package surface is over 027

Parameter Symbol Conditions Min. Typ. Max. Unit

Emitter-Follower VCC(SAT) VC = 15V, IE = -200mA - 1.5 2.5 V Collector Off-State Current IC(OFF) VCC = 40V, VCE = 40V - 2 100 µA

Emitter Off-State Current IE(OFF) VCC = VC = 40V, VE = 0V - - -100 -TOTAL DEVICE

Supply Current ICC Pin 6 = VREF, VCC = 15V - 6 10 mA

OUTPUT SWITCHING CHARACTERISTIC

Rise Time

tR - - 100 200 ns

Common Emitter, Common Collector Fall Time

tF - - 25 100 ns

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5

Typical Application

Pulse Width Modulated Step-down Converter

KA7500C

12 VCC 11 C2 8 C1 3 COMP INPUT - 2 VREF 14 - 15 + 1 + 16 CT 5 RT 6 D.T 4 GND 7 E1 9 E2 10 O.C 13 KSA1010 VI =10V to 40V 1mH, 2A VO=5V IO=1A GND 47Ω 150Ω 1MΩ 5.1KΩ 5.1KΩ 5.1KΩ 150Ω 47KΩ 0.001uF + 50uF 50V + 0.1 + 50uF 10V 0.1uF + 500uF 10V

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Mechanical Dimensions

Package Dimensions in millimeters #1 #8 #9 #16 9.90 ± 0.20 0.39 ± 0.008 1.27 _0.050 5.72 0.225 1.55 ±0.10 0.061 ±0.004 0.05 0.002 6.00 ±0.30 0.236 ±0.012 3.95 ±0.20 0.156 ±0.008 10.30 0.405 MAX 0~8 ° 0.51 _0.020 () 1.80 0.071 MAX0.10 _MAX0.004 MAX MIN + 0.10 -0.05 0.20 + 0.004 -0.002 0.008 + 0.10 -0.05 0.406 + 0.004 -0.002 0.016

16-SOP

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Mechanical Dimensions

(Continued)

Package Dimensions in millimeters #1 #8 #9 #16 6.40 ±0.20 7.62 0.300 2.54 _0.100 0.252 ±0.008 0~15° 0.25+0.10–0.05 0.010+0.004–0.002 3.30 ±0.30 0.130 ±0.012 3.25 ±0.20 0.128 ±0.008 19.40 ± 0.20 0.764 ± 0.008 19.80 0.780 MAX 5.08 0.200 0.38 0.014 MAX MIN 0.81 _0.032 () 0.46 ± 0.10 0.018 ± 0.004 0.059 ± 0.004 1.50 ± 0.10

16-DIP

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DISCLAIMER

FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.

Ordering Information

Product Number Package Operating Temperature

KA7500C 16-DIP

-25 ~ +85°C