Datasheet RH3845MK (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Radiation Hardened High Voltage Synchronous Step-Down Controller |
| Pages / Page | 8 / 1 — DESCRIPTION. ABSOLUTE MAXIMUM RATINGS. (Note 1, 4). PACKAGE INFORMATION. … |
| File Format / Size | PDF / 263 Kb |
| Document Language | English |
DESCRIPTION. ABSOLUTE MAXIMUM RATINGS. (Note 1, 4). PACKAGE INFORMATION. TYPICAL APPLICATION. Order Part Number
Model Line for this Datasheet
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RH3845MW Radiation Hardened High Voltage Synchronous Step-Down Controller
DESCRIPTION ABSOLUTE MAXIMUM RATINGS (Note 1, 4)
The RH3845MW is a high voltage, synchronous, current mode controller for medium to high power, high efficiency VIN ..65V supplies. It offers a wide 4V to 60V input range (7.5V BOOST ..80V minimum start-up voltage). An onboard regulator sim- BOOST to SW..24V plifies the biasing requirements by providing IC power VCC ..24V directly from V SENSE+, SENSE– ...40V IN. SENSE+ to SENSE– .. ±1V Additional features include an adjustable fixed operating SYNC, V frequency synchronizable to an external clock for noise FB and CSS ...5V SHDN Pin Current ..1mA sensitive applications, gate drivers capable of driving large Junction Temperature ... 150°C N-channel MOSFETs, a precision undervoltage lockout, Storage Temperature Range ..–65°C to 150°C low shutdown current, short-circuit protection and a pro- grammable soft-start, and overtemperature protection. All registered trademarks and trademarks are the property of their respective owners. Note that Burst Mode® operation, available in the LT®3845, is not available in the RH3845 version.
PACKAGE INFORMATION
RH3845MW-1 operates in pulse skip mode where reverse inductor current is disallowed. Regulation is achieved at TOP VIEW light loads by skipping cycles. Operation in pulse skip VIN 1 16 BOOST mode yields higher light load efficiency, but higher output SHDN 2 15 TG voltage ripple. CSS 3 14 SW VFB 4 13 VCC RH3845MW-2 operates in forced continuous mode where VC 5 12 BG reverse inductor current is allowed. This mode of opera- SYNC 6 11 PGND tion maintains a constant frequency over all loads mak- fSET 7 10 SENSE+ ing it suitable for noise sensitive applications. However, SGND 8 9 SENSE– forced continuous mode is less efficient at light loads. W PACKAGE 16-LEAD CERPAC
TYPICAL APPLICATION
VIN 20V TO 55V 0.1µF 2.2µF
Order Part Number
100V 1M VIN BOOST RH3845MW-1 47µF 63V SHDN TG Si7370DP RH3845MW-2 1500pF RH3845MW 0.01Ω VOUT 82.5k CSS SW 12V BAS521 15µH 75W BURST_EN VCC B160 33µF Si7370DP VFB BG ×3 20k VC PGND 16.2k 100pF SYNC SENSE+ 2200pF fSET SENSE– 1µF 143k 49.9k SGND 1N4148 RH3845MW TA01a Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Description Typical Application Absolute Maximum Ratings Package Information Table 1: Electrical characteristics Table 2: Electrical characteristics Electrical Characteristics: Burn-In Delta Parameters Electrical Test Requirements Total Dose Bias Circuit — Run Mode Total Dose Bias Circuit — Shutdown Mode Burn-In Circuit—Run Mode Package Description Typical Performance Characteristics
DESCRIPTION ABSOLUTE MAXIMUM RATINGS (Note 1, 4)
The RH3845MW is a high voltage, synchronous, current mode controller for medium to high power, high efficiency VIN ..65V supplies. It offers a wide 4V to 60V input range (7.5V BOOST ..80V minimum start-up voltage). An onboard regulator sim- BOOST to SW..24V plifies the biasing requirements by providing IC power VCC ..24V directly from V SENSE+, SENSE– ...40V IN. SENSE+ to SENSE– .. ±1V Additional features include an adjustable fixed operating SYNC, V frequency synchronizable to an external clock for noise FB and CSS ...5V SHDN Pin Current ..1mA sensitive applications, gate drivers capable of driving large Junction Temperature ... 150°C N-channel MOSFETs, a precision undervoltage lockout, Storage Temperature Range ..–65°C to 150°C low shutdown current, short-circuit protection and a pro- grammable soft-start, and overtemperature protection. All registered trademarks and trademarks are the property of their respective owners. Note that Burst Mode® operation, available in the LT®3845, is not available in the RH3845 version.
PACKAGE INFORMATION
RH3845MW-1 operates in pulse skip mode where reverse inductor current is disallowed. Regulation is achieved at TOP VIEW light loads by skipping cycles. Operation in pulse skip VIN 1 16 BOOST mode yields higher light load efficiency, but higher output SHDN 2 15 TG voltage ripple. CSS 3 14 SW VFB 4 13 VCC RH3845MW-2 operates in forced continuous mode where VC 5 12 BG reverse inductor current is allowed. This mode of opera- SYNC 6 11 PGND tion maintains a constant frequency over all loads mak- fSET 7 10 SENSE+ ing it suitable for noise sensitive applications. However, SGND 8 9 SENSE– forced continuous mode is less efficient at light loads. W PACKAGE 16-LEAD CERPAC
TYPICAL APPLICATION
VIN 20V TO 55V 0.1µF 2.2µF
Order Part Number
100V 1M VIN BOOST RH3845MW-1 47µF 63V SHDN TG Si7370DP RH3845MW-2 1500pF RH3845MW 0.01Ω VOUT 82.5k CSS SW 12V BAS521 15µH 75W BURST_EN VCC B160 33µF Si7370DP VFB BG ×3 20k VC PGND 16.2k 100pF SYNC SENSE+ 2200pF fSET SENSE– 1µF 143k 49.9k SGND 1N4148 RH3845MW TA01a Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Description Typical Application Absolute Maximum Ratings Package Information Table 1: Electrical characteristics Table 2: Electrical characteristics Electrical Characteristics: Burn-In Delta Parameters Electrical Test Requirements Total Dose Bias Circuit — Run Mode Total Dose Bias Circuit — Shutdown Mode Burn-In Circuit—Run Mode Package Description Typical Performance Characteristics
