ISL72991RH (R) Data Sheet June 2004 Radiation Hardened Negative Low Dropout Adjustable Voltage Regulator FN9054.1 Features * Electrically Screened to DSCC SMD # 5962-02503 The radiation hardened ISL72991RH is a low dropout adjustable negative regulator with an output voltage range of -2.25V to -26V. The device features a 1A output current capability, an adjustable current limit pin (ILIM) and a shutdown pin (SD) for easy on/off control. * QML Qualified per MIL-PRF-38535 Requirements * Radiation Environment - Total Dose (Max) . . . . . . . . . . . . . . . . . . . . 300krad(SI) - Latch-Up Immune The device incorporates unique circuitry that enables precision performance over the -55C to +125C temperature range and post-irradiation. Specifications include a reference voltage of -1.25V +40mV/-50mV (max), line regulation of 25mV (max), and load regulation of 15mV (max). * Line Regulation . . . . . . . . . . . . . . . . . . . . . . 25mV (max) Constructed with the Intersil dielectrically isolated Rad Hard Silicon Gate (RSG) BiCMOS process, these devices are immune to Single Event Latch-up and have been specifically designed to provide highly reliable performance in harsh radiation environments. * Dropout Voltage (1A) . . . . . . . . . . . . . . . . . . . . . .1V (max) Specifications for Rad Hard QML devices are controlled by the Defense Supply Center in Columbus (DSCC). The SMD numbers listed here must be used when ordering. Detailed Electrical Specifications for these devices are contained in SMD 5962-02503. A `hotlink' is provided on the Intersil website for downloading. Pinout * Load Regulation . . . . . . . . . . . . 12mV (typ); 15mV (max) * Output Voltage Range . . . . . . . . . . . . . . . . -2.25V to -26V * Dropout Voltage (100mA). . . . . . . . 0.2V (typ); 0.3V (max) * Minimum Load Current. . . . . . . . . . . . . . . . . . . . . . .3.0mA * TTL Input-Level Shutdown (SD); Low = On Applications * Switching Power Supplies * DC/DC Converters * Motor Controllers Ordering Information ORDERING NUMBER ISL72991RHF (FLATPACK CDFP3-F28) TOP VIEW INTERNAL MKT. NUMBER TEMP. RANGE (C) 5962F0250301VXC ISL72991RHVF -55 to 125 5962F0250301QXC ISL72991RHQF -55 to 125 VIN 1 28 VIN 5962F0250301V9A ISL72991RHVX -55 to 125 VIN 2 27 VIN NC 3 26 NC ISL72991RHF/Proto ISL72991RHF/Proto -55 to 125 NC 4 25 NC NC 5 24 NC NC 6 23 NC NC 7 22 NC NC 8 21 NC NC 9 20 NC NC 10 19 NC GND 11 18 ADJ ILIM 12 17 SD VOUT 13 16 VOUT VOUT 14 15 VOUT 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright (c) Intersil Americas Inc. 2002, 2004. All Rights Reserved. All other trademarks mentioned are the property of their respective owners. ISL72991RH Application Information Typical User Application: VIN VOUT VOUT ISL72991RH ADJ CC R1 COUT RCL CIN R2 VIN ILIM SD GND Capacitor Selection FIGURE 1. TYPICAL APPLICATION SCHEMATIC Output Voltage Programming The output voltage of the regulator can be programmed with two external resistors and is described by the following equation: VOUT = VREF x (1+R2/R1) - (IADJ x R2). Output Current Limit Programming IOUT_LIM (A) The output current limit threshold of the regulator can be programmed with a single external resistor connected from ILIM to ground. The current flowing into the ILIM pin is described by the following equation: ILIM = 1V/(RCL + 2400). The graph below shows the relationship between ILIM and the output current limit threshold, IOUT_LIM. ILIM (A) FIGURE 2. IOUT_LIM vs ILIM 2 An input capacitor is required if the regulator is located more than 6 inches from power supply filter capacitors. A 10F solid tantalum capacitor is recommended. An output capacitor of at least 10F must be used to insure stability of the regulator. Additional capacitance may be added as required to improve the dynamic response of the regulator. Solid tantalum and/or ceramic capacitors are recommended. Loop Compensation The output capacitor and ESR comprise a zero in the loop transfer function that must be compensated with a pole to insure loop stability in accordance with the following equation: CC x R2 = COUT x ESR. The compensating capacitor should be a low ESR ceramic type. Layout Guidelines The stability of the regulator is sensitive to layout. It is strongly recommended that a continuous copper ground plane (1 ounce or greater) be used. In addition, component lead lengths and interconnects should be minimized, but should not exceed 1/2 inch. Finally, the return lead of the compensation capacitor (CC) should be connected as close as possible to the GND pin of the IC. ISL72991RH Die Characteristics DIE DIMENSIONS: Backside Finish: 5870m x 5210m (231.1mils x 205.1mils) Thickness: 483m 25.4m (19mils 1mil) INTERFACE MATERIALS: Silicon ASSEMBLY RELATED INFORMATION: Substrate Potential: Glassivation: Unbiased (DI) Type: PSG (Phosphorous Silicon Glass) Thickness: 8.0kA 1.0kA ADDITIONAL INFORMATION: Worst Case Current Density: Top Metallization: <2.0 x 105 A/cm2 Type: AlSiCu Thickness: 16.0kA 2kA Transistor Count: Substrate: Radiation Hardened Silicon Gate, Dielectric Isolation Metallization Mask Layout ISL72991RH All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation's quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 3