Youngkyun Jeong

A 1.1e- temporal noise 1/3.2-inch 8Mpixel CMOS image sensor using pseudo-multiple sampling

The noise performance of CMOS image sensors has improved significantly. The most popular way to reduce readout circuit noise is amplifying pixel output using a preamplifier at the foremost stage of readout chain to suppress the noise of following readout chains in high analog gain [1–3]. Another approach is multiple sampling which can reduce temporal noise of pixel and readout circuit by sampling the same pixel repeatedly and processing (generally averaging) the sampled data [4, 5]. However, both approaches require additional circuitry in the column readout chain which requires extra silicon area and power consumption. Furthermore, it is hard to implement a decent per-column amplifier in a small pixel pitch sensor, such as 1.4µm pixel, because of narrow layout space. In addition, the second approach requires longer readout time proportional to the number of samples. This paper presents a cost-effective low noise CMOS image sensor readout chain using pseudo-multiple sampling technique.

A 5.2-Gb/s Low-Swing Voltage-Mode Transmitter With an AC-/DC-Coupled Equalizer and a Voltage Offset Generator

This paper describes a voltage-mode transmitter with an AC-/DC-coupled equalizer. A dual-loop regulator controls the tap-weight coefficient for the DC-coupled equalizer while maintaining the output matching condition. An AC-coupling technique is employed to enhance the edge rate and reduce the burden of the DC-coupled equalizer. The transmitter also supports the ability to add a DC differential voltage offset into the output signal so that the voltage margin of the link can be measured. The transmitter was fabricated using a 0.13-um CMOS technology. When 240- mVPP, 5.2-Gb/s data are sent over 20-inch FR4 channels, the eye of the received data has a voltage margin of 60 mV and a peak-to-peak jitter of 40 ps. The proposed transmitter consumes 5.86 mW from a 1.2-V supply while operating at 5.2 Gb/s.

A 12-Gb/s Stacked Dual-Channel Interface for CMOS Image Sensor Systems

We propose a dual-channel interface architecture that allocates high and low transition-density bit streams to two separate channels. The transmitter utilizes the stacked drivers with charge-recycling to reduce the power consumption. The direct current (DC)-coupled receiver front-end circuits manage the common-mode level variations and compensate for the channel loss. The tracked oversampling clock and data recovery (CDR), which realizes fast lock acquisition below 1 baud period and low logic latency, is shared by the two channels. Fabricated in a 65-nm low-power complementary metal-oxide semiconductor (CMOS) technology, the dual-channel transceiver achieves 12-Gb/s data rate while the transmitter consumes 20.43 mW from a 1.2-V power supply.

A 12-Gb/s dual-channel transceiver for CMOS image sensor systems

We propose a dual-channel interface architecture that allocates high and low transition-density bit streams to two separate channels. The transmitter utilizes the stacked drivers with charge-recycling to reduce the power consumption. The DC-coupled receiver front-end circuits deal with the common-mode level variations and compensate for the channel loss. The tracked oversampling CDR which realizes fast lock acquisition below 1 baud period and low logic latency is shared by the two channels. Fabricated in a 65-nm low-power CMOS technology, the dual-channel transceiver achieves 12-Gb/s data rate while the transmitter consumes 20.43mW from a 1.2V power supply.

An Inductive-coupling Link with a Complementary Switching Transmitter and an Integrating Receiver

A transceiver for a high-speed inductivecoupling link is proposed. The bi-phase modulation (BPM) signaling scheme is used due to its good noise immunity. The transmitter utilizes a complementary switching method to remove glitches in transmitted data. To increase the timing margin on the receiver side, an integrating receiver with a pre-charging equalizer is employed. The proposed transceiver was implemented via a 130-nm CMOS process. The measured timing window for a 10 -12 bit error rate (BER) at 1.8 Gb/s was 0.33 UI.