SI8251-IM Silicon Laboratories Inc, SI8251-IM Datasheet
SI8251-IM
Specifications of SI8251-IM
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SI8251-IM Summary of contents
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Features Single-chip, Flash-based digital power controller Supports isolated and non-isolated applications Enables new system capabilities such as: - Adaptive dead-time control for higher efficiency - Nonlinear control for faster ...
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Si8250/1/2 2 Rev. 1.0 ...
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Section 1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . ...
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Si8250/1/2 1. Electrical Specifications Table 1. Absolute Maximum Ratings* Parameter Ambient temperature under bias Storage temperature Voltage on any Port0 Pin with respect to GND Voltage on all other pins with respect to GND Voltage on V with respect to ...
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Table 3. Reference DAC Electrical Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter Resolution LSB size Integral nonlinearity (INL) Differential nonlinearity (DNL) Settling ...
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Si8250/1/2 Table 4. ADC0 (12-Bit ADC) Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter DC Accuracy Resolution Integral nonlinearity Differential nonlinearity Offset error ...
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Table 5. ADC1 Specifications TA = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified. DD Parameter Sampling frequency Resolution LSB size Differential input voltage range Common-mode input voltage range ...
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Si8250/1/2 Table 7. Peak Current Limit Detector Electrical Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter IPK input to DPWM output latency Threshold ...
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Table 8. DPWM Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter Clock frequency Resolution Time resolution SYNC signal minimum LOW time SYNC pulse ...
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Si8250/1/2 Table 10. Comparator0 Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter V IN Low-speed supply current Full-speed supply current Hysteresis Low power ...
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... The last 512 bytes of memory are reserved. Conditions Min I = 8 RST = 0.0 Time from last system clock rising edge to start of reset tion at location 0x0000 100 Conditions Min Si8250 32768 Si8251, Si8252 16384 Rev. 1.0 Si8250/1/2 Typ Max Units — — 0.7 — — DD — ...
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Si8250/1/2 Table 13. Port I/O DC Electrical Characteristics T = –40 to +125 °C, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified. A Parameters Port0 input voltage tolerance Port1 input voltage tolerance Output high voltage Output low ...
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Table 15. 25MHz Oscillator Specifications T = –40 to +125 ° 2.5 V, SYSCLK = 25 MHz, PLLCLK = 200 MHz unless otherwise specified Parameter Frequency Start-up time Power supply sensitivity Temperature coefficient Supply current Shutdown ...
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Si8250/1/2 2. Benefits of Digital Power Control Digitally-controlled power systems have the following key advantages over analog implementations: In-system programmability: Virtually all aspects of digital controller behavior can be changed in software locally or remotely and without hardware modification. This ...
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Product Description System Management Processor VDD 2% 25 Mhz OSC, SYSCLKIN and LFO RESET CONTROL HARDWARE DEBUG DEBUG PORT INTERRUPT CONTROL VSENSE VSENSE VREF REFDAC VREF IPK Control Processor System Management Processor VDD 50MIPS 8051 CPU SYSCLKIN and Memory ...
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Si8250/1/2 3.1. System Operation Figure 2 shows the Si8250/1/2 controlling a non- isolated dc/dc converter operating in digital voltage mode control. The output voltage signal connects to the V input through a resistive divider, limiting the SENSE common-mode voltage range ...
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The first filter stage is a PID filter providing one pole and two zeros. The second stage is selectable: a two-pole, low-pass filter (LPF) for the fastest possible response SINC (multiple zero) decimation filter for quieter ...
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Si8250/1/2 4. Design Tools The Si8250DK development kit (Figure 3) contains everything required to develop applications with the Si825x family of digital power controllers. This kit supports all phases of power supply development from controller design through real-time system debugging. ...
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Example Applications The Si825x is the ideal choice for digitally-controlled switched mode power supplies. This section provides a quick overview of the Si825x in an isolated half-bridge dc/dc converter and a single-phase point-of-load converter. Reference designs are available for ...
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Si8250/1/2 5.2. Single-Phase Point of Load (POL) Converter 400 KHz Si8252 based single phase POL converter block diagram is shown in Figure 8. DPWM outputs PH1 and PH2 control the gates of the buck and synchronous switching ...
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Layout Considerations The mixed-signal nature of the Si8250/1/2 mandates clean bias supplies and ground returns best to provide separate ground planes for analog, digital, and power switch returns. These planes should tie together at only one point ...
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Si8250/1/2 In both cases, the bias supplies must be filtered using low ESR/ESL capacitors placed close to the IC pins. Thick copper traces should be connected to the bias pins ( and the ground pins (GND, GNDA) ...
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Pin Descriptions: Si8250/1/2 32-pin LQFP RST/C2CK 1 IPK 2 VSENSE 3 Si8250/1/2 GNDA 4 Top View VDDA 5 6 VREF 7 P1.0/VIN/AIN0 8 P1.1/AIN1 Figure 13. Example Pin Configurations Name QFN-28 LQFP-32 Pin # Pin# RST/C2CK 1 IPK 2 ...
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Si8250/1/2 Table 17. Pin Descriptions (Continued) Name QFN-28 LQFP-32 Pin # Pin# P0.5 17 P0.4 18 P0.3/XCLK 19 P0.2 20 P0.1 21 P0.0 22 PH6 23 PH5 24 PH4 25 V — DD GND — PH3 26 PH2 27 PH1 ...
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... Ordering Guide Ordering Number Flash Memory Si8250-IQ Si8250-IM Si8251-IQ Si8251-IM Si8252-IQ Si8252- PWM Outputs Rev. 1.0 Si8250/1/2 UART Package Yes LQFP-32 Yes QFN-28 Yes LQFP-32 Yes QFN-28 No LQFP-32 No QFN-28 25 ...
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Si8250/1/2 9. Package Outline: 32LQFP Figure 14 illustrates the package details for the 32-pin LQFP version of the Si8250/1/2. Table 18 lists the values for the dimensions shown in the illustration. Figure 14. 32-pin LQFP Package Diagram 26 Rev. 1.0 ...
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Table 18. LQFP-32 Package Dimensions Dimension Min A — A1 0.05 A2 1.35 b 0. 0.45 aaa bbb ccc ddd Θ 0° Notes: All dimensions shown are in millimeters (mm) unless otherwise ...
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Si8250/1/2 10. Package Outline: 28QFN Figure 15 illustrates the package details for the 28-lead QFN version of the Si8250/1/2. Table 19 lists the values for the dimensions shown in the illustration. Figure 15. 28-lead Quad Flat No-lead (QFN) Package Diagram ...
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Table 19. QFN-28 Package Dimensions Dimension Min A 0. 2.90 L 0.45 aaa bbb ddd eee Z Y Notes: 1. All dimensions shown are in millimeters (mm) unless otherwise ...
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Si8250/1 OCUMENT HANGE IST Revision 0.7 to Revision 0.8 Updated DPWM phase output drive-high and drive- low resistance in Table 8, “DPWM Specifications,” on page 9. Revision 0.8 to Revision 0.9 Updated Table 5, “ADC1 Specifications,” on ...
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N : OTES Rev. 1.0 Si8250/1/2 31 ...
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