BU79100G-LATR

Datasheet A/D Converter Series Successive Approximation A/D Converter 12 bit, 0.5 MSPS to 1 MSPS, 2.7 V to 5.25 V, 1-channel, SPI Interface BU79100G-LA General Description Key Specifications This is the product guarantees long time support in industrial market. The BU79100G-LA is a general purpose, 12 bit 1-channel successive approximation AD converter. The sampling rate of BU79100G-LA ranges from 0.5 MSPS to 1 MSPS. ◼ Supply Voltage Range: ◼ Sampling Rate: ◼ Power Consumption: (In 1MSPS Operation) ◼ ◼ ◼ ◼ ◼ Features Long Time Support Product for Industrial Applications Maximum 1 MSPS Sampling Rate Low Power Consumption Small SSOP6 Package Compatible with SOT23-6 Serial Interface Compatible with SPI/QSPI/MICROWIRE ◼ Operational Supply Voltage Range: 2.7 V to 5.25 V ◼ Single-ended Input ◼ Output Code in Straight Binary Format ◼ ◼ ◼ ◼ ◼ 2.70 V to 5.25 V 0.5 MSPS to 1.0 MSPS 8 mW @VA = 5 V (Typ) 1.5 mW @VA = 3 V (Typ) INL: -1.1 LSB to +1.0 LSB DNL: -1.0 LSB to +1.0 LSB SNR: 71.5 dB @ VA = 3 V (Typ) SINAD: 71.0 dB @ VA = 3 V (Typ) Operating Temperature Range: -40 °C to +85 °C Package SSOP6 W (Typ) x D (Typ) x H (Max) 2.9 mm x 2.8 mm x 1.25 mm Applications ◼ ◼ ◼ ◼ Industrial Equipment Instrumentation and Control Systems Motor Control Systems Data Acquisition Systems Typical Application Circuit VOLTAGE REFERENCE VA 10µF 0.1µF CSB BU1S12S1BG-M BU79100G-LA ANALOG SIGNAL SOURCE 330Ω SCLK 330Ω VIN 22Ω 1000pF to 0.1µF 〇Product structure : Silicon integrated circuit www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 14 • 001 MICROPROCESSOR or DSP SDATA 100Ω GND 〇This product has no designed protection against radioactive rays. 1/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Contents General Description ........................................................................................................................................................................ 1 Features.......................................................................................................................................................................................... 1 Applications .................................................................................................................................................................................... 1 Key Specifications .......................................................................................................................................................................... 1 Package .......................................................................................................................................................................................... 1 Typical Application Circuit ............................................................................................................................................................... 1 Pin Configuration ............................................................................................................................................................................ 3 Pin Descriptions .............................................................................................................................................................................. 3 Block Diagram ................................................................................................................................................................................ 3 Absolute Maximum Ratings ............................................................................................................................................................ 4 Thermal Resistance ........................................................................................................................................................................ 4 Recommended Operating Conditions ............................................................................................................................................. 5 Electrical Characteristics................................................................................................................................................................. 6 Timing Specifications ...................................................................................................................................................................... 7 Term Definitions .............................................................................................................................................................................. 8 Typical Performance Curves ........................................................................................................................................................... 9 Description of Functions ............................................................................................................................................................... 12 Application Example ..................................................................................................................................................................... 15 I/O Equivalence Circuit ................................................................................................................................................................. 16 Operational Notes ......................................................................................................................................................................... 17 Ordering Information ..................................................................................................................................................................... 18 Marking Diagram .......................................................................................................................................................................... 18 Physical Dimension and Packing Information ............................................................................................................................... 19 Revision History ............................................................................................................................................................................ 20 www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 2/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Pin Configuration (TOP VIEW) VA 1 6 CSB GND 2 5 SDATA VIN 3 4 SCLK Pin Descriptions Pin No. Pin Name 1 VA Power supply pin. This voltage is the full scale of the analog input. Function 2 GND Ground pin. This voltage level is the zero scale of the analog input. 3 VIN Analog input pin. The voltage range must be between 0 V and VA. 4 SCLK Digital clock input pin. 5 SDATA Digital data output pin. 6 CSB Chip select pin. A/D conversion starts at the falling edge of this signal. Block Diagram www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 3/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Absolute Maximum Ratings (Ta = 25 °C) Parameter Symbol Rating Unit VA 5.7 V Analog Input Voltage VIN -0.3 to VA+0.3 V Digital Input Voltage VDIN -0.3 to +5.7 V Tjmax 125 °C Tstg -55 to +125 °C Supply Voltage Maximum Junction Temperature Storage Temperature Range Caution 1: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over the absolute maximum ratings. Caution 2: Should by any chance the maximum junction temperature rating be exceeded the rise in temperature of the chip may result in deterioration of the properties of the chip. In case of exceeding this absolute maximum rating, design a PCB with thermal resistance taken into consideration by increasing board size and copper area so as not to exceed the maximum junction temperature rating. Thermal Resistance (Note 1) Parameter Symbol Thermal Resistance (Typ) 1s(Note 3) 2s2p(Note 4) Unit SSOP6 Junction to Ambient θJA 376.5 185.4 °C/W Junction to Top Characterization Parameter(Note 2) ΨJT 40 30 °C/W (Note 1) Based on JESD51-2A (Still-Air). (Note 2) The thermal characterization parameter to report the difference between junction temperature and the temperature at the top center of the outside surface of the component package. (Note 3) Using a PCB board based on JESD51-3. (Note 4) Using a PCB board based on JESD51-7. Layer Number of Measurement Board Single Material Board Size FR-4 114.3 mm x 76.2 mm x 1.57 mmt Top Copper Pattern Thickness Footprints and Traces 70 μm Layer Number of Measurement Board 4 Layers Material Board Size FR-4 114.3 mm x 76.2 mm x 1.6 mmt Top 2 Internal Layers Bottom Copper Pattern Thickness Copper Pattern Thickness Copper Pattern Thickness Footprints and Traces 70 μm 74.2 mm x 74.2 mm 35 μm 74.2 mm x 74.2 mm 70 μm www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 4/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Recommended Operating Conditions Parameter Symbol Min Typ Max Unit VA 2.70 - 5.25 V Analog Input Voltage VIN 0 - VA V Digital Input Voltage VDIN 0 - 5.25 V Operating Temperature Topr -40 +25 +85 °C Clock Frequency fSCLK 10 - 20 MHz fS 0.5 - 1.0 MSPS Supply Voltage Sampling Rate www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 5/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Electrical Characteristics Unless otherwise specified, Ta = -40 °C to +85 °C (typical: Ta = 25 °C), VA = 2.7 V to 5.25 V, fSCLK = 20 MHz, fS = 1 MSPS Parameter Symbol Min Typ Max Unit Conditions Resolution with No missing codes RES - 12 - bit Integral Non-linearity INL -1.1 - +1.0 LSB VA = 2.7 V to 3.6 V, 25 °C Differential Non-linearity DNL -1.0 - +1.0 LSB VA = 2.7 V to 3.6 V, 25 °C Offset Error OE -1.2 ±0.2 +1.2 LSB VA = 2.7 V to 3.6 V, 25 °C Gain Error GE -1.2 ±0.3 +1.2 LSB VA = 2.7 V to 3.6 V, 25 °C 71 - dB VA = 2.7 V to 3.6 V, 25 °C Statistic Converter Characteristics VA = 2.7 V to 3.6 V Dynamic Converter Characteristics (fIN = 100 kHz, VIN = -0.02 dBFS) Signal to Noise and Distortion Ratio1 SINAD1 Signal to Noise and Distortion Ratio2 70 SINAD2 68 70 - dB VA = 4.75 V to 5.25 V, 25 °C Signal to Noise Ratio1 SNR1 70.8 71.5 - dB VA = 2.7 V to 3.6 V, 25 °C Signal to Noise Ratio2 SNR2 68.8 71.0 - dB VA = 4.75 V to 5.25 V, 25 °C Total Harmonic Distortion THD - -80 - dB VA = 2.7 V to 3.6 V Spurious-free Dynamic Range SFDR - 82 - dB VA = 2.7 V to 3.6 V Effective Number of Bits1 ENOB1 11.3 11.5 - bit VA = 2.7 V to 3.6 V, 25 °C Effective Number of Bits2 Inter-modulation Distortion1 (Second Order Term) Inter-modulation Distortion2 (Third Order term) Full Power Band Width1 ENOB2 11.0 11.3 - bit IMD1 - -78 - dB IMD2 - -76 - dB fPBW1 - 10.1 - MHz VA = 4.75 V to 5.25 V, 25 °C VA = 5.25 V, 103.5 kHz, 113.5 kHz VA = 5.25 V, 103.5 kHz, 113.5 kHz VA = 5 V Full Power Band Width2 fPBW2 - 7.2 - MHz VA = 3 V tAD - 4.3 - ns VA = 5 V VA = 5 V Aperture Delay Aperture Jitter Clock Frequency Sampling Rate Track/Hold Acquisition Time tAJ - 30 - ps fSCLK 10 - 20 MHz fS 500 k - 1M SPS tACQ - - 350 ns Analog Input Characteristics Input Voltage Range VIN 0 - VA V Input DC Leakage Current ILEAK -1.0 ±0.1 +1.0 µA VIN = 0 V or VA Input Capacitance1 CINA1 - 28 - pF track mode, VA = 5 V Input Capacitance2 CINA2 - 4 - pF hold mode, VA = 5 V High Input Voltage1 VIH1 2.4 - - V VA = 5.25 V High Input Voltage2 VIH2 2.1 - - V VA = 3.6 V Low Input Voltage1 VIL1 - - 0.8 V VA = 5 V Low Input Voltage2 VIL2 - - 0.4 V VA = 3 V Input Current IIND -1.0 ±0.1 +1.0 µA VIND = 0 V or VA Input Capacitance CIND - 2.5 - pF - V ISOURCE = 200 µA Digital Input Characteristics Digital Output Characteristics Output High Voltage1 VOH1 Output High Voltage2 VOH2 - VA-0.1 - V ISOURCE = 1 mA Output Low Voltage1 VOL1 - 0.02 0.40 V ISINK = 200 µA Output Low Voltage2 VOL2 - 0.1 - V ISINK = 1 mA IOZ -10.0 ±0.1 +10.0 µA VOZ = 0 V or VA COUT - 2 - pF Operational Current Consumption1 IA1 - 1.6 2.8 mA VA = 5.25 V, fS = 1 MSPS Operational Current Consumption2 IA2 - 0.5 1.2 mA VA = 3.6 V, fS = 1 MSPS High-Z Leakage Current High-Z Output Capacitance VA-0.20 VA-0.03 Current Consumption www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 6/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Timing Specifications Unless otherwise specified, Ta = -40 °C to +85 °C (Typical: Ta = 25 °C), VA = 2.7 V to 5.25 V, fSCLK = 10 M to 20 MHz, CL = 25 pF Parameter Symbol Min Typ Max Unit Conditions Conversion Time tCONV - 16 - SCLK CSB Pulse Width t1 10 - - ns CSB Setup Time t2 10 - - ns SDATA Enable Time t3 - - 20 ns SDATA Access Time1 t4 - - 40 ns VA = 2.7 V to 3.6 V SDATA Access Time2 t4 - - 20 ns VA = 4.75 V to 5.25 V SCLK Low Pulse Width t5 0.4xtSCLK - - ns SCLK High Pulse Width t6 0.4xtSCLK - - ns SDATA Hold Time1 t7 7 - - ns VA = 2.7 V to 3.6 V SDATA Hold Time2 t7 5 - - ns VA = 4.75 V to 5.25 V SDATA Disable Time1 t8 6 - 25 ns VA = 2.7 V to 3.6 V SDATA Disable Time2 t8 5 - 25 ns VA = 4.75 V to 5.25 V CSB Hold Time t9 10 - - ns t10 10 - - ns tQUIET 50 - - ns tPOWUP - 1 - µs tTHROUGHPUT 1 - 20 µs SCLK Setup Time Quiet Time Power-Up Time Throughput Period Hold mode Track mode t1 CSB tCONV t9 t2 1 2 3 t6 4 t10 5 13 15 14 16 SCLK t4 t3 t5 t7 t8 tQUIET SDATA ZERO ZERO ZERO ZERO DB11 DB10 DB2 DB1 DB0 High-Z High-Z 4 LEADING ZEROS tTHROUGHPUT (a) If SCLK is high at the falling edge of CSB Hold mode Track mode t1 CSB tCONV t9 t2 1 2 3 t6 4 t10 5 13 15 14 16 SCLK t4 t3 t5 t7 t8 tQUIET SDATA ZERO ZERO ZERO ZERO High-Z DB11 DB10 DB2 DB1 DB0 High-Z 4 LEADING ZEROS tTHROUGHPUT (b) If SCLK is low at the falling edge of CSB Figure 1. Serial Interface Timing Chart (Note 5) When the BU79100G-LA is used at the sampling frequency of 1 MSPS, it is recommended to hold SCLK high at the falling edge of CSB as shown in Figure 1(a). (See also “3. Serial Interface” on page 13.) www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 7/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Term Definitions ACQUISITION TIME: At the 13th rising edge of SCLK, the mode is changed from Hold mode to Track mode and the sampling capacitor starts to be charged. It is the time when the voltage of the sampling capacitor equals input voltage from the charge start. APERTURE DELAY: It is defined as the time when the input voltage is held since a sampling capacitor was separated with outside by a falling edge of CSB. APERTURE JITTER: The variation in the aperture delays in sampling operations. Aperture jitter gets to affect output noise. INTEGRAL NON-LINEARLITY (INL): It is a measure of the deviation of each individual code from a line drawn from zero scale (0.5 LSB below the first code transition) through full scale (0.5 LSB above the last code transition). The deviation of any given code from this straight line is measured from the center of that code value. DIFFERENTIAL NON-LINEARLITY (DNL): It is the measure of the maximum deviation from the ideal step size of 1 LSB. OFFSET ERROR (OE): It is the deviation of the first code transition “(000…000) to (000…001)” from the ideal of 0.5 LSB. FULL SCALE ERROR (FSE): It is the deviation of the last code transition “(111…110) to (111…111)” from the ideal of “VA–1.5 LSB”. GAIN ERROR (GE): It is defined as full scale error minus offset error. TOTAL HARMONIC DISTORTION (THD): It is the ratio, expressed in dB or dBc, of the RMS total of the first five harmonic components at the output to the RMS level of the input signal frequency as seen at the output. THD is calculated as where Af1 is the RMS power of the input frequency at the output and A f2 through Af6 are the RMS power in the first 5 harmonic frequencies. SIGNAL TO NOISE AND DISTORTION RATIO (SINAD): It is the ratio, expressed in dB, of the RMS value of the input signal to the RMS value of all other spectral components below half the sampling frequency, including harmonics but excluding DC component. EFFECTIVE NUMBER OF BITS (ENOB): It is another method of specifying Signal to Noise and Distortion Ratio. ENOB is defined as “(SINAD–1.76) / 6.02” and says that the converter is equivalent to a perfect A/D converter of this number of bits. SIGNAL TO NOISE RATIO (SNR): It is the ratio, expressed in dB, of the RMS value of the input signal to the RMS value of all other spectral components below half the sampling frequency, not including harmonics and DC component. SPURIOUS FREE DYNAMIC RANGE (SFDR): It is the difference, expressed in dB, between the RMS value of the input signal to the RMS value of the peak spurious spectral component, where a peak spurious spectral component is any spurious signal present in the output spectrum that is not present at the input. CONVERSION TIME: It is the required time for the A/D converter to convert the input signal to the digital code. THROUGHPUT PERIOD: It is the period that should be used as an interval time between any adjacent conversions. www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 8/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Typical Performance Curves 1.00 1.00 0.75 0.75 INL [LSB]INL [LSB] Integral Non-linearity: DNL [LSB]DNL [LSB] Differential Non-linearity: (Reference Data) Unless otherwise noted, Ta = 25 °C. 0.50 0.25 0.00 -0.25 -0.50 -0.75 0.50 0.25 0.00 -0.25 -0.50 -0.75 -1.00 -1.00 0 1024 2048 3072 0 4096 2048 3072 4096 OUTPUT CODE CODE OUTPUT OUTPUT CODE OUTPUT CODE Figure 3. Integral Non-linearity vs OUTPUT CODE (VA = 3 V, fSCLK = 10 MHz, fS = 500 kSPS) Figure 2. Differential Non-linearity vs OUTPUT CODE (VA = 3 V, fSCLK = 10 MHz, fS = 500 kSPS) 1.00 1.00 0.75 0.75 INL [LSB] Integral Non-linearity: INL [LSB] DNL [LSB] Differential Non-linearity: DNL [LSB] 1024 0.50 0.25 0.00 -0.25 -0.50 -0.75 -1.00 0.50 0.25 0.00 -0.25 -0.50 -0.75 -1.00 0 1024 2048 3072 4096 0 OUTPUT CODE OUTPUT CODE 2048 3072 4096 OUTPUT CODE CODE OUTPUT Figure 4. Differential Non-linearity vs OUTPUT CODE (VA = 3 V, fSCLK = 20 MHz, fS = 1 MSPS) www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 1024 Figure 5. Integral Non-linearity vs OUTPUT CODE (VA = 3 V, fSCLK = 20 MHz, fS = 1 MSPS) 9/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Typical Performance Curves – continued (Reference Data) Unless otherwise noted, Ta = 25 °C, fIN = 100 kHz. 1.5 1.0 INL [LSB]INL [LSB] Integral Non-linearity: DNL [LSB]DNL [LSB] Differential Non-linearity: 1.5 VA = 5 V 0.5 VA = 3 V 0.0 VA = 3 V -0.5 VA = 5 V -1.0 VA = 5 V 1.0 0.5 VA = 3 V 0.0 VA = 3 V -0.5 VA = 5 V -1.0 -1.5 -1.5 0 5 10 15 0 20 SINAD [dB] Signal to Noise and Distortion Ratio: SINAD1, SINAD2 [dB] SNRS[dB] Signal to Noise Ratio: NR1, SNR2 [dB] 80 75 VA = 5 V VA = 3 V 65 60 5 10 15 20 ClockFrequency: Frequency [MHz] Clock fSCLK [MHz] Figure 8. Signal to Noise Ratio vs Clock Frequency www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 15 20 Figure 7. Integral Non-linearity vs Clock Frequency Figure 6. Differential Non-linearity vs Clock Frequency 0 10 Clock Frequency: fSCLK[MHz] [MHz] Clock Frequency Clock Frequency: fSCLK[MHz] [MHz] Clock Frequency 70 5 75 VA = 3 V 70 VA = 5 V 65 60 55 0 5 10 15 20 Clock fSCLK [MHz] ClockFrequency: Frequency [MHz] Figure 9. Signal to Noise and Distortion Ratio vs Clock Frequency 10/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Typical Performance Curves – continued (Reference Data) Unless otherwise noted, Ta = 25 °C, fIN = 100 kHz. -70 THD [dB]THD [dB] Total Harmonic Distortion: SFDRRange: [dB] SFDR [dB] Spurious-free Dynamic 95 90 85 VA = 3 V 80 VA = 5 V 75 0 5 10 15 -75 -80 VA = 3 V -85 -90 -95 -100 20 0 Clock fSCLK [MHz] ClockFrequency: Frequency [MHz] -20 -20 Amplitude [dBFS] Amplitude [dBFS] Amplitude [dBFS] Amplitude [dBFS] 0 -40 -60 -80 -80 -120 -120 200 250 0 100 200 300 400 500 Frequency [kHz] Frequency [kHz] Frequency [kHz] Frequency [kHz] Figure 12. Amplitude vs Frequency (VA = 5 V, fSCLK = 10 MHz, fS = 500 kSPS) www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 20 -60 -100 150 15 -40 -100 100 10 Figure 11. Total Harmonic Distortion vs Clock Frequency 0 50 5 Clock Frequency: fSCLK[MHz] [MHz] Clock Frequency Figure 10. Spurious-free Dynamic Range vs Clock Frequency 0 VA = 5 V Figure 13. Amplitude vs Frequency (VA = 5 V, fSCLK = 20 MHz, fS = 1 MSPS) 11/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Description of Functions 1. Overview of A/D Conversion Process BU79100G-LA is a successive-approximation A/D converter designed with a charge-redistribution D/A converter. Simplified schematics of the A/D converter are shown in Figure 14 and Figure 15. Figure 14 shows the A/D converter in Track mode: the switch SW1 is in the position A, SW2 is closed and balances the comparator. Then, the sampling capacitor is charged with the analog input voltage VIN. Figure 15 shows the A/D converter in Hold mode. When a conversion starts, the A/D converter goes into Hold mode: SW2 becomes open, SW1 connects the sampling capacitor to ground through the pin B and the comparator loses its balance. The control logic controls the input voltage of the comparator via the sampling capacitors of the charge-redistribution D/A converter to get the comparator back into a balanced state. A/D conversion finishes when the comparator balances again. The control logic also generates the output code of the A/D converter. CHARGE REDISTRIBUTION DAC VIN A SAMPLING CAPACITOR VIN A SW1 SAMPLING CAPACITOR SW1 CONTROL LOGIC SW2 B GND CHARGE REDISTRIBUTION DAC GND VA 2 Figure 14. Track mode CONTROL LOGIC SW2 B VA 2 Figure 15. Hold mode 2. Ideal Transfer Characteristics Figure 16 shows the ideal transfer characteristics of BU79100G-LA. Code transitions occur midway between successive integer LSB values, such as 0.5 LSB, 1.5 LSB, and so on. The LSB size for the BU79100G-LA is VA / 4096. The output code format of the A/D converter is straight binary. 111...111 ・・・ ・・ ADC CODE 111...110 111...000 1LSB 1 LSB==VVAA/ /4096 4096 011...111 ・・・ 000...010 000...001 000...000 0.5LSB 0.5 LSB 00V V +V 1.5LSB LSB +V A A–-1.5 ANALOG INPUT Figure 16. Ideal Transfer Characteristics www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 12/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Description of Functions – continued 3. Serial Interface The serial interface timing is shown in Figure 17. When CSB goes low, both a conversion process and data transfer are started. At the falling edge of CSB, SDATA changes its state from High-Z to Low, the converter moves from Track mode to Hold mode. A tracked input signal is sampled and held for conversion at this point. The converter returns from Hold mode back to Track mode at the rising edge of SCLK subsequent to the 13th falling edge of it. SDATA goes back to High-Z at the 16th falling edge of SCLK or at the rising edge of CSB. After a conversion, the quiet time tQUIET must be satisfied before the next conversion triggered by the falling edge of CSB. Sixteen SCLK cycles are needed to read a complete data of the A/D conversion from BU79100G-LA. First, four leading zeros come out from SDATA. Then, the 12 bit data comes out bit by bit, starting from the MSB. The first zero is clocked out at the falling edge of CSB. The remaining leading 3 zeros and data bits are clocked out to SDATA at the falling edge of SCLK; the host IC, the receiver of the A/D conversion data, is intended to receive the data at the subsequent falling edge of SCLK. To perform A/D conversion properly, the BU79100G-LA needs at least 16 SCLK cycles while CSB is low. If an A/D conversion is interrupted in the middle of the conversion with CSB going to high before the 16 th SCLK falling edge, the following A/D conversion may not be performed normally. Therefore, it is necessary that equal to or more than 16 falling edges of SCLK exist while CSB is low. In addition, SCLK should be held either high or low at the falling edge of CSB. If SCLK is low at the falling edge of CSB, as shown in Figure 17(b), a Hold mode time length is about a half clock period longer than one if SCLK is high as shown in Figure 17(a). Therefore, when the BU79100G-LA is used at the sampling frequency of 1 MSPS, it is recommended to hold SCLK high at the falling edge of CSB, as shown in Figure 17(a), in order to ensure sufficient Track mode time for the maximum acquisition time. Hold mode Track mode CSB 1 2 3 4 5 6 7 8 9 DB11 DB10 DB9 DB8 DB7 10 11 12 13 14 15 16 SCLK SDATA High-Z ZERO ZERO ZERO ZERO DB6 DB5 DB4 DB3 DB2 DB1 DB0 High-Z 4 LEADING ZEROS (a) If SCLK is high at the falling edge of CSB Hold mode Track mode CSB 1 2 3 4 5 6 7 8 9 DB11 DB10 DB9 DB8 DB7 10 11 12 13 14 15 16 SCLK SDATA High-Z ZERO ZERO ZERO ZERO DB6 DB5 DB4 DB3 DB2 DB1 DB0 High-Z 4 LEADING ZEROS (b) If SCLK is low at the falling edge of CSB Figure 17. Serial Interface Timing www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 13/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Description of Functions – continued 4. Dummy Conversion Dummy conversions are necessary in the following cases. (1) A/D conversion after power-up The first A/D conversion data after applying power to the BU79100G-LA is invalid. Therefore, a dummy conversion is necessary after power-up. In addition, the power-up time is satisfied with a cycle of the dummy conversion. after power-up dummy conversion CSB 1 16 1 16 SCLK SDATA VALID DATA INVALID DATA Figure 18. A/D conversion after power-up (2) A/D conversion after a stop period more than the maximum throughput time The BU79100G-LA may stop performing A/D conversion between some A/D conversion cycles. If the maximum limit of the throughput period of 20 μs is violated, the first A/D conversion data after the resumption is not valid similar to the case after power-up. Therefore, a dummy conversion cycle is necessary. more than max throughput time dummy conversion CSB 1 16 1 16 1 16 SCLK SDATA INVALID DATA VALID DATA VALID DATA Figure 19. A/D conversion after a long suspension www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 14/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Application Example VOLTAGE REFERENCE 10 10µF µF VA 0.1 0.1µF µF CSB BU1S12S1BG-M BU79100G-LA ANALOG SIGNAL SOURCE 330 330 Ω Ω SCLK 330Ω Ω 330 VIN 22 22ΩΩ 1000 pF 1000pF toto0.1 0.1µF µF MICROPROCESSOR or DSP SDATA 100 100 Ω Ω GND Figure 20. Application Circuit As shown in Figure 20, a power supply pin connects voltage source and put two bypass capacitors for the high frequency and low frequency noise between VA and GND to make the maximum use of the A/D converter’s capability. Ceramic capacitors of 0.1 μF and 1 μF to 10 μF are to be used as bypass capacitor for BU79100G-LA. Especially, the capacitor of 0.1 μF should be placed as close to the VA pin of BU79100G-LA as possible. Because the voltages of VA and GND are used as the reference voltages for the A/D converter, the deviation of the supply voltage directly affects the full scale and has much influence on its characteristics. Therefore, the fully stable supply voltage should be connected to VA. The output impedance of the analog input signal source should be small enough. Charge in the sampling capacitor is swept out to the VIN pin at the transition from Hold mode to Track mode because of the difference of the voltage between the input signal voltage and the sampling capacitor voltage. This charge could cause undesirable voltage deviation. If influence of the deviation remains at the transition from Track mode to Hold mode, it could cause the conversion error. If a buffer amplifier is used to get low output impedance, high-speed response is required of the buffer amplifier. A decoupling capacitor and a resister on the VIN analog input could support the amplifier to reduce the influence of the charge. The voltage fluctuation on the supply and ground pins is caused by the charge and discharge of the digital input and output pins through the digital signals. This fluctuation can be reduced by inserting resisters serially to the digital input and output pins. The resistance values must be small enough not to cause critical delay errors. It is more effective to place these resisters as close to the digital pins as possible. www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 15/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA I/O Equivalence Circuit (1) Analog Input Pin The equivalent analog input circuit is shown in Figure 21. The diodes, D1 and D2, are placed for ESD protection. If the analog input voltage is more than “VA+0.3 V”, or less than “GND–0.3 V”, these diodes are turned on and forward current is generated. This current might cause malfunction or irreversible damage to BU79100G-LA. The capacitance value of the C1 in Figure 21 is typically 4 pF, derived from the package parasitic capacitance. The R1 is the resistance of the track/hold switch, typically 500 Ω. The C2 is the sampling capacitance of BU79100G-LA, and the capacitance value is typically 24 pF. VA DD1 1 RR1 1 VIN CC1 1 D2 D 2 SW1 OPEN : HOLD MODE CLOSE : TRACK MODE C2 C 2 Figure 21. Analog Input Equivalent Circuit (2) Digital Input and Output Pins The equivalent digital input circuit is shown in Figure 22. Digital input pins, CSB and SCLK, don’t have any diodes to VA. Thus, the maximum rating of “VA+0.3 V” is not applied to these digital input pins. Digital input voltage range is 5.25 V in ground reference regardless of the supply voltage VA. This enables BU79100G-LA to be interfaced with a wide range of logic levels, independent of the supply voltage. VA VA SCLK SDATA CSB Figure 22. Equivalent Digital Input Circuit www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 16/20 Figure 23. Equivalent Digital Output Circuit TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Operational Notes 1. Reverse Connection of Power Supply Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when connecting the power supply, such as mounting an external diode between the power supply and the IC’s power supply pins. 2. Power Supply Lines Design the PCB layout pattern to provide low impedance supply lines. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and aging on the capacitance value when using electrolytic capacitors. 3. Ground Voltage Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition. 4. Ground Wiring Pattern When using both small-signal and large-current ground traces, the two ground traces should be routed separately but connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal ground caused by large currents. Also ensure that the ground traces of external components do not cause variations on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance. 5. Recommended Operating Conditions The function and operation of the IC are guaranteed within the range specified by the recommended operating conditions. The characteristic values are guaranteed only under the conditions of each item specified by the electrical characteristics. 6. Inrush Current When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may flow instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power supply. Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring, and routing of connections. 7. Testing on Application Boards When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply should always be turned off completely before connecting or removing it from the test setup during the inspection process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during transport and storage. 8. Inter-pin Short and Mounting Errors Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin. Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and unintentional solder bridge deposited in between pins during assembly to name a few. 9. Unused Input Pins Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and cause unexpected operation of the IC. So unless otherwise specified, unused input pins should be connected to the power supply or ground line. 10. Regarding the Input Pin of the IC In the construction of this IC, P-N junctions are inevitably formed creating parasitic diodes or transistors. The operation of these parasitic elements can result in mutual interference among circuits, operational faults, or physical damage. Therefore, conditions which cause these parasitic elements to operate, such as applying a voltage to an input pin lower than the ground voltage should be avoided. Furthermore, do not apply a voltage to the input pins when no power supply voltage is applied to the IC. Even if the power supply voltage is applied, make sure that the input pins have voltages within the values specified in the electrical characteristics of this IC. 11. Ceramic Capacitor When using a ceramic capacitor, determine a capacitance value considering the change of capacitance with temperature and the decrease in nominal capacitance due to DC bias and others. www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 17/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Ordering Information B U 7 9 1 0 0 G Package G: SSOP6 LAT R - Product Class LA: for Industrial Applications Packaging and forming specification TR: Embossed tape and reel Marking Diagram Part Number Marking G R SSOP6 (TOP VIEW) Pin 1 Mark www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 LOT Number 18/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Physical Dimension and Packing Information Package Name www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 SSOP6 19/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 BU79100G-LA Revision History Date Revision 05.Feb.2021 001 Changes New Release www.rohm.com © 2021 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 20/20 TSZ02201-0M2M0G720020-1-2 05.Feb.2021 Rev.001 Notice Precaution on using ROHM Products 1. If you intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Note 1), aircraft/spacecraft, nuclear power controllers, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance. Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific Applications. (Note1) Medical Equipment Classification of the Specific Applications JAPAN USA EU CHINA CLASSⅢ CLASSⅡb CLASSⅢ CLASSⅢ CLASSⅣ CLASSⅢ 2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which a failure or malfunction of our Products may cause. The following are examples of safety measures: [a] Installation of protection circuits or other protective devices to improve system safety [b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure 3. Our Products are not designed under any special or extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any special or extraordinary environments or conditions. If you intend to use our Products under any special or extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of product performance, reliability, etc, prior to use, must be necessary: [a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents [b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust [c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves [e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items [f] Sealing or coating our Products with resin or other coating materials [g] Use of our Products without cleaning residue of flux (Exclude cases where no-clean type fluxes is used. However, recommend sufficiently about the residue.); or Washing our Products by using water or water-soluble cleaning agents for cleaning residue after soldering [h] Use of the Products in places subject to dew condensation 4. The Products are not subject to radiation-proof design. 5. Please verify and confirm characteristics of the final or mounted products in using the Products. 6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse, is applied, confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect product performance and reliability. 7. De-rate Power Dissipation depending on ambient temperature. When used in sealed area, confirm that it is the use in the range that does not exceed the maximum junction temperature. 8. Confirm that operation temperature is within the specified range described in the product specification. 9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in this document. Precaution for Mounting / Circuit board design 1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product performance and reliability. 2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products, please consult with the ROHM representative in advance. For details, please refer to ROHM Mounting specification Notice-PAA-E © 2015 ROHM Co., Ltd. All rights reserved. Rev.004 Precautions Regarding Application Examples and External Circuits 1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the characteristics of the Products and external components, including transient characteristics, as well as static characteristics. 2. You agree that application notes, reference designs, and associated data and information contained in this document are presented only as guidance for Products use. Therefore, in case you use such information, you are solely responsible for it and you must exercise your own independent verification and judgment in the use of such information contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of such information. Precaution for Electrostatic This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron, isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control). Precaution for Storage / Transportation 1. Product performance and soldered connections may deteriorate if the Products are stored in the places where: [a] the Products are exposed to sea winds or corrosive gases, including Cl 2, H2S, NH3, SO2, and NO2 [b] the temperature or humidity exceeds those recommended by ROHM [c] the Products are exposed to direct sunshine or condensation [d] the Products are exposed to high Electrostatic 2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is exceeding the recommended storage time period. 3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads may occur due to excessive stress applied when dropping of a carton. 4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of which storage time is exceeding the recommended storage time period. Precaution for Product Label A two-dimensional barcode printed on ROHM Products label is for ROHM’s internal use only. Precaution for Disposition When disposing Products please dispose them properly using an authorized industry waste company. Precaution for Foreign Exchange and Foreign Trade act Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign trade act, please consult with ROHM in case of export. Precaution Regarding Intellectual Property Rights 1. All information and data including but not limited to application example contained in this document is for reference only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any other rights of any third party regarding such information or data. 2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the Products with other articles such as components, circuits, systems or external equipment (including software). 3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to manufacture or sell products containing the Products, subject to the terms and conditions herein. Other Precaution 1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM. 2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written consent of ROHM. 3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the Products or this document for any military purposes, including but not limited to, the development of mass-destruction weapons. 4. The proper names of companies or products described in this document are trademarks or registered trademarks of ROHM, its affiliated companies or third parties. Notice-PAA-E © 2015 ROHM Co., Ltd. All rights reserved. Rev.004 Datasheet General Precaution 1. Before you use our Products, you are requested to carefully read this document and fully understand its contents. ROHM shall not be in any way responsible or liable for failure, malfunction or accident arising from the use of any ROHM’s Products against warning, caution or note contained in this document. 2. All information contained in this document is current as of the issuing date and subject to change without any prior notice. Before purchasing or using ROHM’s Products, please confirm the latest information with a ROHM sales representative. 3. The information contained in this document is provided on an “as is” basis and ROHM does not warrant that all information contained in this document is accurate and/or error-free. ROHM shall not be in any way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccuracy or errors of or concerning such information. Notice – WE © 2015 ROHM Co., Ltd. All rights reserved. Rev.001