Si9113 New Product Vishay Siliconix High-Voltage Current Mode PWM Controller for ISDN Power Supplies BiC/DMOS Technology Current Mode Control Max 50% Duty Cycle Operation 1.3-MHz Error Amp Up to 500-kHz Internal Oscillator Soft-Start 0.6-V Fast Over-Current Protection <5-A Supply Current for +VIN <18 V 23.5-V to 200-V Input Voltage Range Programmable Start/Stop Capability Internal Start-Up Circuit Power_Good Output Si9113 is a current mode PWM controller for ISDN power supplies. In a 14-pin SOIC package, it provides all necessary functions to implement a single-switch PWM with a minimum of external parts. To maximize the circuit integration, the Si9113 is designed with a 200-V depletion mode MOSFET capable of powering directly off the high input bus without an external start-up circuit. The Start and Stop input voltage thresholds can be programmed within the operating input voltage range by means of a resistor divider, provided +VIN (Start) > +VIN (Stop). The internal clock frequency is set with a single external resistor and is capable of capacitor-coupled external synchronization. In order to satisfy the stringent ambient temperature requirements, the Si9113 is rated to handle the industrial range of –40C to 85C. VIN (23.5 V to 200 V) VOUT Start-Up Drive Current Stop/Start Power_Good VREF = 1.3 V Comparator Fast Current Limit Comparator For Detailed Block Diagram See Page 7 Document Number: 71093 S-99453—Rev. A . 29-Nov-99 . www.siliconix.com FaxBack 408-970-5600 1 Si9113 New Product Vishay Siliconix VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 V Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150C VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 V Power Dissipation (Package)a 14-Pin SOIC (Y Suffix)b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 900 mW Logic Inputs (OSC IN, OSC OUT, PWR_GOOD) . . . –0.3 V to VCC + 0.3 V or 10 mA Linear Inputs (FB, VREF, SENSE, SS) . . . . . . . . . . . . –0.3 V to VCC + 0.3 V Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65 to 150C Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40 to 85C Thermal Impedance (QJA) 14-Pin SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140C/W Notes a. Device mounted with all leads soldered or welded to PC board. b. Derate 7.2 mW/C above 25C. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23.5 V to 200 V VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 V to 14 V Digital Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to VCC Linear Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to VCC – 3 V FOSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 kHz to 500 kHz SPECIFICATIONSa Limits Test Conditions Unless Otherwise Specified –40 to 85C Symbol VCC = 10 V, +VIN = 48 V, ROSC = 390 kW Tempb Minc Typd Maxc Unit Output Voltage VREF OSCIN = – VIN (OSC Disabled) RL = 10 MW Room Full 1.275 1.26 1.3 1.3 1.325 1.34 V Short Circuit Current ISREF VREF = –VIN Room –25 –10 mA IREF = 0 to –0.5 mA Full 10 40 VCC = 10 to 14 V Full 2 5 VUVSTART Turn-On Full 8.10 8.8 9.50 VUVSTOP Turn-Off Full 8.10 8.8 9.50 Parameter Reference Load Regulation Line Regulation DVREF mV UVLO Under Voltage Lockout Input Bias Current ISTART ISTOP VSTOP = 8 V, VSTART = 8 V Room 0.05 Room 0.05 Pre-Regulated VCC VREG Room 8.5 9.0 9.5 UVLO for VCC VCCUV Room 7.9 8.4 8.9 VREG – VCCUV VD Room 0.3 0.6 V mA V PWR_Good Comparator Rise Time trpg Fall Time tfpg Output Logic Low CPWR_Good PWR Good = 100 nF ISINK = 2.5 mA Room 35 Room 25 Room 0.4 mS mS 0.8 V Soft-Start SS Current ISS Room 11 mA Output Inhibit Voltage VSS Room 3.3 V Oscillator Maximum Frequencye Initial Accuracy fMAX fOSC Df/f Voltage Stability Temperature Coefficiente TOSC Maximum Duty Cycle DMAX www.siliconix.com FaxBack 408-970-5600 2 ROSC = 0 Room ROSC = 390 k (Note f) Room 500 80 100 120 ROSC = 180 k (Note f ) Room 160 200 240 Df/f = (f [14 V] – f [10 V]) / f [10 V] Room 10 15 % Full 450 650 ppm/C fOSC = 100 kHz Room 50 kHz kH % Document Number: 71093 S-99453—Rev. A . 29-Nov-99 Si9113 New Product Vishay Siliconix SPECIFICATIONSa Limits Test Conditions Unless Otherwise Specified –40 to 85C Symbol VCC = 10 V, +VIN = 48 V, ROSC = 390 kW Tempb Minc Typd Open Loop Voltage Gaine AVOL OSC IN = – VIN Room 50 60 Input BIAS Current IBIAS VFB = 1.3 V Room –1 1 mA Feedback Input Voltage VFB FB Tied to COMP, OSC IN = – VIN Full 1.28 1.32 V Parameter Maxc Unit Error Amplifier Dynamic Output Impedancee ZOUT Room Unity Gain Bandwidthe BW Room Output Current IOUT Power Supply Rejectione 1 1 dB 2 1.3 –5 kW MHz Source VFB = 0.8 V Room –1 Sink VFB = 1.8 V Room 0.12 0.15 Room 50 70 0.5 0.6 0.7 V 100 150 ns mA PSRR dB Current Limit Comparator Threshold Voltage VSOURCE VFB = 0 V Full td VSENSE = 0.85 V, See Figure 1 Full Output High Voltage VOH IOUT = –10 mA Room Full Output Low Voltage VOL IOUT = 10 mA Room Full Rise Time tr Fall Time tf CL = 500 p pF (10% to t 90%) Delay to Outpute Output Drive 9.7 9.5 0.3 0.5 Room 40 75 Room 40 75 V ns Supply ICC VCC = 10 V, ROSC = 390 kW VUVUP vVIN v 200 V Full 1 1.4 IVIN Excluding I From Resistive Divider of Stop and Start Pins Room 75 100 IVIN +VIN v 18 V, VSTART (Pin 14) < 8.8 V Room 2 5 Supply Current Supply Current UVLO Mode mA m mA Notes a. Refer to PROCESS OPTION FLOWCHART for additional information. b. Room = 25C, Full = –40 to 85C. c. The algebraic convention whereby the most negative value is a minimum and the most positive a maximum. d. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing. e. Guaranteed by design, not subject to production test. f. CSTRAY Pin 8 = v 5 pF. SENSE 0.85 V – 50% tr v 10 ns 0 td VCC 90% OUTPUT 0 – FIGURE 1. Delay Time for Current Sense Document Number: 71093 S-99453—Rev. A . 29-Nov-99 www.siliconix.com FaxBack 408-970-5600 3 Si9113 New Product Vishay Siliconix VREF vs. Temperature (VIN = 48 V) 1.306 VUVSTART/VUVSTOP vs. Temperature 9.1 9.0 VCC = 14 V VUVSTART /VUVSTOP (v) VREF – (V) 1.304 1.302 VCC = 12 V VCC = 10 V 1.300 8.9 8.8 8.7 8.6 8.5 1.298 –50 –25 0 25 50 75 8.4 –50 100 –25 0 50 75 100 Temperature (C) Temperature (C) Output Frequency vs. Oscillator Resistance Supply Current vs. Output Frequency 2.0 300 1.6 VCC = 10 V VCC = 14 V I CC (mA) FOUT (kHz) 25 100 1.2 VCC = 10 V VCC = 12 V 0.8 0.4 0 10 10 100 1000 0 2000 50 100 FOSC (kW) Output Frequency vs. Supply Voltage 200 250 300 Soft-Start Current vs. Temperature 24 13 ROSC = 1 MW 12 22 85C VCC = 10 V 11 25C 20 I SS ( m A) FOUT (kHz) 150 FOUT (kHz) –40C 18 10 9 16 8 14 9 10 11 12 VCC (V) www.siliconix.com FaxBack 408-970-5600 4 13 14 15 7 –40 –20 0 20 40 60 80 100 Temperature (C) Document Number: 71093 S-99453—Rev. A . 29-Nov-99 Si9113 New Product Vishay Siliconix UVLO Supply Current vs. VIN Output Rise Time vs. Load 80 10 VCC = 10 V Rise/Fall Time (nS) 60 I IN ( (mA) 85C 1 25C 40 20 –40C 0 0.1 11 13 15 17 19 21 0 200 VIN (V) 400 600 800 COUT (pF) Efficiency vs. Output Power 90 VIN = 28 V 80 Efficiency (%) 70 VIN = 48 V 60 VIN = 99 V 50 40 30 20 10 0 200 400 600 800 1000 WO (mW) Document Number: 71093 S-99453—Rev. A . 29-Nov-99 www.siliconix.com FaxBack 408-970-5600 5 Si9113 New Product Vishay Siliconix SOIC-14 STOP 1 14 START VIN 2 13 COMP SENSE 3 12 FB Si9113 PWR_GOOD 4 –VIN 5 10 SS DRIVER 6 9 OSCOUT VCC 7 8 OSCIN Part Number 11 VREF Si9113DY Package Bulk –40 to 85C Si9113DY-T1 Eval Kit Top View Temperature Range Tape and Reel Temperature Range Board Type –10 to 70C Surface Mount and Th H l Thru-Hole Si9113D1 Si9113D2 Pin Number Name 1 STOP 2 +VIN 3 SENSE 4 PWR_GOOD 5 –VIN 6 DRIVER 7 VCC 8 OSCIN 9 OSCOUT 10 SS 11 VREF 12 FB Set up the stop threshold of +VIN for VCC via resistive dividers Input voltage to UVLO and Start-Up circuitry Current sense amplifier input for current mode control and OCP. Logic high PWR_Good signal indicates FB voltage is within regulation. Ground pin MOSFET gate drive signal. Supply voltage to internal circuitry and MOSFET gate drive. ROSC terminal ROSC terminal, square waveform output Soft-Start, time programmed by capacitor value. 1.3-V reference. Decoupled with 0.1-F capacitor. Inverting input of an error amplifier. 13 COMP Error amplifier output for external compensation network. 14 START Set up the start threshold of +VIN for VCC via resistive dividers www.siliconix.com FaxBack 408-970-5600 6 Function Document Number: 71093 S-99453—Rev. A . 29-Nov-99 Si9113 New Product Vishay Siliconix 8 COMP 13 9 VCC OSCIN OSCOUT OSC PWR_GOOD FB VREF Clock (1/2 fOSC) 4 Error Amplifier 12 – 11 3.6 V + – + – PWM Comparator R + Q MOS Driver S SS 6 + Ref Gen – 10 DRIVER C/L Comparator 5 0.6 V 3 VCC VIN STOP START –VIN SENSE 7 2 1 14 Enable Programmable Start/Stop Circuit Start-Up Pre-Regulator Start-Up The Si9113 start-up circuit prevents the internal circuits from turning on until the voltage on the +VIN pin, via the resistor divider R3, R4, R5, is sufficiently positive such that the voltage across R3 (VSTART) is >8.8 V (typical value for the internal reference VUVSTART [see Figure 2]). When this occurs, the internal 1.3-V reference, soft-start and oscillator circuits are enabled. A constant current source provides the current to the external soft-start capacitor, which allows the output voltage to rise gradually without overshoot. The output drive circuit is disabled until the soft-start voltage reaches 3.3 V. The controller is continuously powered in the state until the VIN voltage falls and VSTOP drops below 8.8 V (the typical value for Document Number: 71093 S-99453—Rev. A . 29-Nov-99 the internal reference VUVSTOP). The user can program the +VIN START and +VIN STOP voltage with the external resistor divider R3–R5 (see Figure 2) as follows: V IN(START) + V IN(STOP) + ǒ ǒ R3 ) R4 ) R5 R5 R3 ) R5 R5 Ǔ Ǔ V UVSTART V UVSTOP (1) (2) Since VUVSTART = VUVSTOP = 8.8 V (typical) the hysteresis voltage can be expressed as: www.siliconix.com FaxBack 408-970-5600 7 Si9113 Vishay Siliconix DV IN + ǒ Ǔ R4 R5 V UVSTART New Product (3) VCC Circuit The depletion MOSFET process allows the Si9113 controller to power directly from the high input bus voltage. Once VUVSTART is met, the pre-regulator start-up circuit generates the 9.0-V VCC voltage. The VCC voltage is used internally to power the IC as well as providing the drive current for the external MOSFET. An internal VCC circuit is disabled once a higher external voltage (X10 V) is applied to this pin. If VCC is below VCCUV, the Si9113 will inhibit the driver output switching. period eliminating any chance of undesirable noise frequency. When the output load current decreases to 0 A, the controller is forced to enter the pulse skipping mode. This is a natural phenomenal for all controllers since the duty cycle cannot decrease linearly to 0%. Error Amplifier The reference voltage of Si9113 is set at 1.3 V. The reference voltage is internally connected to the non-inverting input of error amplifier. The reference is decoupled with 0.1-mF capacitor. The error amplifier gain-bandwidth product and slew rate are critical parameters which determine the transient response of converter. The transient response is the function of both small and large signal responses. The small signal response is determined by the converter closed loop bandwidth and phase margin while the large signal is determined by the error amplifier dv/dt and the inductor di/dt slew rate. Besides the inductance value, the error amplifier determines the converter response time. In order to minimize the response time, the Si9113 is designed with 1.3-MHz error amplifier gain-bandwidth product to generate the widest converter bandwidth. Soft-Start Current Limit The soft-start circuit provides a constant 10-mA current to external capacitor attached to SS pin. A constant soft-start current forces a gradual increase in duty cycle which in turn ensures gradual output voltage rise without overshooting. The soft-start time is programmed by the capacitance value. Over current protection circuit is provided by monitoring the voltage on the Sense pin. Once the current sense voltage reaches 0.6V peak, the output drive stage is disabled for the remainder of the clock cycle. REF Power_Good Comparator Oscillator The oscillator consists of a ring of CMOS inverters, capacitors, and a capacitor discharge switch. An external resistor, ROSC, between the OSCIN and OSCOUT pins sets the frequency. The maximum frequency is obtained when ROSC = 0 W. A frequency divider in the logic section limits the switch duty cycle to 50% by locking the switching frequency to one-half of the oscillator frequency. The PWR_Good signal indicates the status of output voltage. If the output voltage and VCC are within regulation, the PWR_Good signal generates a logic high output by monitoring the voltage on COMP and VCC pins. If either one is out of regulation, a logic low PWR_Good signal is generated. The capacitor at the PWR_Good pin determines the rise time of the power good signal, once all the conditions are met for power good. The PWR_Good signal is an open collector output capable of sinking 2.5 mA. PWM Mode MOSFET Gate Drive As the load and line voltage vary, the switching frequency remains constant. The switching frequency is programmed by the ROSC value as shown by the oscillator curve. In the PWM mode, a duty cycle pulse is generated for each switching www.siliconix.com FaxBack 408-970-5600 8 The DRIVER pin is designed to drive the low-side n-channel MOSFET. Typically, the driver stage is sized to sink and source 200-mA of peak current when VCC = 12 V. Document Number: 71093 S-99453—Rev. A . 29-Nov-99 Si9113 New Product Vishay Siliconix 28 – 99 V +VIN 4 3 –VIN T1 XFMR_EPC17 1 BR1 AC + AC – + C1 22 mF 160 V 2 ESIG DF02S C4 1 mF R13 D1 2.7 W ESIG R9 20 kW 7 D3 C12 0.1 mF C10 220 mF 10 V C10 NS2 2.2 mF 50 V 3 6 3 + D4* BZX84C43 1 COM2 NS3 3.3 V C5 0.1 mF 9 NP 5 B130LB 8 COM1 R1 R10 13 kW 40 V D2 1 1 MW C7 8 7 6 OSCOUT 0.1 mF 12 4 GND 4 PWR_G VREF 3 FB ICS COMP VIN START STOP 13 14 R2 C8 300 kW 0.01 mF R1 1 1 kW 2 C9 220 pF 1 Si9113 C3 100 pF Q01 Si3420DV 5 SS 11 3 DR 10 0.001 mF C6 1, 2, 5, 6 VCC OSCIN 9 R2 2W 1/ W 2 R3 5.1 MW R4 1 MW R5 3.96 MW *Optional FIGURE 2. Dual Output Flyback Converter with 2% Regulation for 3.3 V ( As used on Demo Board—DB1) Document Number: 71093 S-99453—Rev. A . 29-Nov-99 www.siliconix.com FaxBack 408-970-5600 9 Si9113 New Product Vishay Siliconix 28 – 99 V +VIN 4 3 –VIN T1 XFMR_EPC17 4 BR1 AC + AC – 40 V D2 1 + C1 22 mF 160 V 2 ESIG DF02S R13 2.7 W D1 C10 NS2 2.2 mF 50 V 3 5 C4 1 mF 3.3 V B130LB 9 NS3 D3 2 NS1 R10 1 6 C11 220 mF 10 V R1 1 MW C7 7 VCC OSCIN 9 OSCOUT 11 0.1 mF 12 3 Q01 Si3420DV 5 4 GND 4 PWR_G VREF FB ICS COMP VIN START STOP 13 14 R2 C8 300 kW 0.01 mF C12 0.1 mF 1, 2, 5, 6 DR SS 0.001 mF C6 C5 0.1 mF 6 10 + COM1 12.7 kW 8 D4* BZX84C43 COM2 1 ESIG 8 NP R9 89 kW 3 + 3 R11 2 1 kW C9 470 pF 1 Si9113 R2 2W 1/ W 2 R3 5.1 MW C3 100 pF R4 1 MW R5 3.96 MW *Optional FIGURE 3. Dual Output Flyback Converter with Moderately Regulated Outputs (As used on Demo Board DB-2) www.siliconix.com FaxBack 408-970-5600 10 Document Number: 71093 S-99453—Rev. A . 29-Nov-99