TY - GEN
T1 - 8.11 A 48V-to-5V Buck Converter with Triple EMI Suppression Circuit Meeting CISPR 25 Automotive Standards
AU - Kao, Yi Hsiang
AU - Hung, Chieh Sheng
AU - Chang, Hui Hsuan
AU - Huang, Wei Cheng
AU - Guo, Rong Bin
AU - Tsai, Hsing Yen
AU - Chen, Ke Horng
AU - Zeng, Kuo Lin
AU - Lin, Ying Hsi
AU - Lin, Shian Ru
AU - Tsai, Tsung Yen
N1 - Publisher Copyright:
© 2024 IEEE.
PY - 2024
Y1 - 2024
N2 - In automotive-used switching regulator applications, the characteristic of extreme conversion ratio (48V to 5V) and high switching frequency (fSW) will give rise to considerable electromagnetic interference (EMI) issues, which is a tremendous obstacle to meeting CISPR 25 automotive standards. As shown in Fig. 8.11.1 (top), if VBattery and VSW nodes are considered, the EMI problem can be divided into two areas. Region I is caused by fSW harmonic tones (<50 MHz) and Region II is caused by VSW spurious ringing and high dv/dt of VSW (>50 MHz). Prior techniques utilize spread-spectrum modulation (SSM) to reduce noise at VSW by increasing fSW spread spectrum (ΔfSW) or decreasing modulation frequency (fM) in Region I [1-3, 6]. Moreover, EMI filters can be used to mitigate EMI problems in Region II [4, 5]. However, fSW harmonic overlap issues are more common in Region II, making EMI suppression less effective in conventional SSM techniques. Spurious Noise Compression (SNC) scheme in [1] modulates fSW with noise (Vn) from Zener diode to largely flatten EMI spikes. Besides, with the aid of Tri-Slope Gate Driving (TSGD), dv/dt and di/dt at VSW during rising edge can be finely tuned to further lower the noise level. Unfortunately, [1] cannot alleviate EMI at VBattery and TSGD cannot control the falling edge of VSW. The multi-rate SSM (MR-SSM) technique in [2] solves the EMI power aliasing spikes by modulating fSW with predefined multi-rate ontime pattern and adaptively synchronizing off-time; however, it fails to optimize the EMI performance as Random SSM does since the fM of MR-SSM will lie in a predefined value. The condition-adaptive Δf3-EMI control in [3] takes input voltage (VIN), load current (ILOAD), and spectrum overlapping issues into consideration to adjust ΔfSW and fM to optimize the EMI reduction. However, it lacks slew rate control when turning on and off the power switches, which induces unsatisfactory EMI reduction in Region II.
AB - In automotive-used switching regulator applications, the characteristic of extreme conversion ratio (48V to 5V) and high switching frequency (fSW) will give rise to considerable electromagnetic interference (EMI) issues, which is a tremendous obstacle to meeting CISPR 25 automotive standards. As shown in Fig. 8.11.1 (top), if VBattery and VSW nodes are considered, the EMI problem can be divided into two areas. Region I is caused by fSW harmonic tones (<50 MHz) and Region II is caused by VSW spurious ringing and high dv/dt of VSW (>50 MHz). Prior techniques utilize spread-spectrum modulation (SSM) to reduce noise at VSW by increasing fSW spread spectrum (ΔfSW) or decreasing modulation frequency (fM) in Region I [1-3, 6]. Moreover, EMI filters can be used to mitigate EMI problems in Region II [4, 5]. However, fSW harmonic overlap issues are more common in Region II, making EMI suppression less effective in conventional SSM techniques. Spurious Noise Compression (SNC) scheme in [1] modulates fSW with noise (Vn) from Zener diode to largely flatten EMI spikes. Besides, with the aid of Tri-Slope Gate Driving (TSGD), dv/dt and di/dt at VSW during rising edge can be finely tuned to further lower the noise level. Unfortunately, [1] cannot alleviate EMI at VBattery and TSGD cannot control the falling edge of VSW. The multi-rate SSM (MR-SSM) technique in [2] solves the EMI power aliasing spikes by modulating fSW with predefined multi-rate ontime pattern and adaptively synchronizing off-time; however, it fails to optimize the EMI performance as Random SSM does since the fM of MR-SSM will lie in a predefined value. The condition-adaptive Δf3-EMI control in [3] takes input voltage (VIN), load current (ILOAD), and spectrum overlapping issues into consideration to adjust ΔfSW and fM to optimize the EMI reduction. However, it lacks slew rate control when turning on and off the power switches, which induces unsatisfactory EMI reduction in Region II.
UR - http://www.scopus.com/inward/record.url?scp=85188109088&partnerID=8YFLogxK
U2 - 10.1109/ISSCC49657.2024.10454539
DO - 10.1109/ISSCC49657.2024.10454539
M3 - Conference contribution
AN - SCOPUS:85188109088
T3 - Digest of Technical Papers - IEEE International Solid-State Circuits Conference
SP - 164
EP - 166
BT - 2024 IEEE International Solid-State Circuits Conference, ISSCC 2024
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2024 IEEE International Solid-State Circuits Conference, ISSCC 2024
Y2 - 18 February 2024 through 22 February 2024
ER -