RF Exposure Info

FCC ID: BCGA1876

RF Exposure Info

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FCCID_4045740

FCC Test Results FCC ID: BCGA1876 Date: September 12-14, 2018 Test Method: Per FCC KDB Inquiry iPad EUT S/N: DLXWX007KNPN Pencil S/N GQXXC1W2JKM9 RF Exposure Measurements of Wireless Charging Transmitter Per FCC KDB Inquiry Purpose: The purpose of this test report is to determine the worst-case H-Field and E-Field levels emitted by the wireless charging transmitter of the EUT Host to the pencil per FCC KDB Inquiry to determine qualification for SAR test exclusion. Wireless Charging Maximum Output Power from Host: 7.44 W Wireless Charging Operating Frequency: 127.7 kHz Test results reported herein relate only to the item(s) tested. Note: This revised Test Report (S/N: 1C1806050010-12-R2.BCG) supersedes and replaces the previously issued test report on the same subject device for the same type of testing as indicated. Please discard or destroy the previously issued test report(s) and dispose of it accordingly. © 2018 PCTEST LAB Page 1 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results Test Equipment Manufacturer Model Description Cal. Date Cal. Due Date Serial Number Narda ELT-400 Exposure Level Tester 5/30/2017 5/30/2019 N-0727 Narda 2300-90.20 B-Field Probe 12/14/2017 12/14/2019 C-0271 Narda ELT-400 Exposure Level Tester 2/27/2017 2/27/2019 N-0701 Narda 2300-90.20 B-Field Probe 3/21/2017 3/21/2019 C-0232 Narda EHP-200A E and H Field Probe 6/22/2017 6/22/2019 170WX70613 Analyzer Definitions • Optimal Placement (Max Coupling) = Optimal pencil location as positioned by the magnets that hold the pencil in place. • Min Coupling = Misalignment as described in the KDB inquiry. • Charging Profiles: Charge Rate Battery State of Charge Charge Duration in Min 10.0 C 0 - 4% 0m 12s 3.0 C 4 - 12% 2m 0s 2.5 C 12 - 85% 22m 0s 1 C (Trickle) 85 - 100% 20m 0s X, Y, Z Axis Description Figure 1 Pencil Alignment X, Y, Z Axis • For the X axis, the positive direction is towards the tail of the pencil, and the negative direction is towards the writing tip of the pencil. • For the Y axis, the negative direction is increasing air gap • For the Z axis, the positive direction is towards the front screen of device, and the negative direction is towards the back shell of the device. © 2018 PCTEST LAB Page 2 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results Verification of H-Field Control (HFC) Algorithm • Tx coil current (ITX) and Rx current (IRECT) and efficiency are used to define the hard thresholds used in H-Field control algorithm. H-field control algorithm will always limit the Max H-fields below worst-case value. • Measurement procedure was performed per FCC KDB Inquiry. • Data in the following table were recorded from real time streaming command prompt output that monitors the current and efficiency of the EUT Host’s wireless charging function with pencil. Charging Measurement Cases Pencil alignment ITx (A) IRECT (A) condition 0 10C 0.91 0.22 0 3C 0.52 0.11 Optimal Alignment (Max Coupling) 0 2.5C 0.51 0.09 0 1C 0.46 0.06 Min Coupling, ∆z = -2.8 mm 10C 1.54 0.22 shifting pencil towards back ∆z = -3.0 mm 3C 0.93 0.11 (-Z) until charging throttles, then ∆z = -3.2 mm 2.5C 1.00 0.09 move back by 0.2 mm ∆z = -3.2 mm 1C 0.88 0.06 ∆z = +4 mm 10C 1.54 0.22 Min Coupling, shifting pencil towards Display ∆z = +4.4 mm 3C 0.93 0.11 (+Z) until charging throttles, then ∆z = +4.6 mm 2.5C 1.01 0.09 move back by 0.2 mm ∆z = +4.8 mm 1C 0.88 0.06 ∆y = -1.5 mm 10C 1.54 0.22 Min Coupling, shifting pencil away from ∆y = -1.7 mm 3C 0.96 0.11 iPad(-Y) until charging throttles, ∆y = -1.7 mm 2.5C 0.96 0.09 then move back by 0.2 mm ∆y = -2.1 mm 1C 0.91 0.06 © 2018 PCTEST LAB Page 3 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results ∆x = +3.4 mm 10C 1.45 0.22 Min Coupling, shifting pencil upward in lateral ∆x = +3.8 mm 3C 0.95 0.11 plane(+X) until charging throttles, ∆x = +4 mm 2.5C 0.99 0.09 then move back by 0.2 mm ∆x = +4.2mm 1C 0.85 0.06 Min Coupling, ∆x = -3.4 mm 10C 1.47 0.22 shifting pencil downward in ∆x = -3.8. mm 3C 0.95 0.11 lateral plane(-X) until charging throttles, then ∆x = -4 mm 2.5C 1.00 0.09 move back by 0.2 mm ∆x = -4.2 mm 1C 0.87 0.06 © 2018 PCTEST LAB Page 4 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results H-Field and E-Field Measurements • Measurement procedure was performed per FCC KDB Inquiry. • H-Field testing was performed with calibrated field probes (ELT-400). • E-Field testing was performed with calibrated field probe (EHP-200A). • Measurements were performed on the front screen (Top), back shell (Bottom), and side of the EUT where the pencil is charging (Side). Probe Distance Measured Measured Measurement Pencil Charge from the Probe plane H-Field E-Field Cases alignment Profile DUT (A/m) (V/m) (mm) 0 0 Top 45.5 5.4 Optimal Placement 0 0 Bottom 10C 29.8 5.0 (Max Coupling) 0 0 Side 16.7 2.6 0 ∆z = -2.8 mm Top 61.6 5.7 Min coupling, shifting pencil towards back (-Z) until charging 0 ∆z = -2.8 mm Bottom 10C 39.3 7.8 throttles, then move back in by 0.2 mm 0 ∆z = -2.8 mm Side 22.5 3.0 0 ∆z = +4 mm Top 53.9 6.0 Min coupling, shifting pencil towards Display (+Z) until charging 0 ∆z = +4 mm Bottom 10C 35.7 5.3 throttles, then move back in by 0.2 mm 0 ∆z = +4 mm Side 21.7 4.7 © 2018 PCTEST LAB Page 5 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results Min coupling, shifting pencil towards back (-Z) until charging 0 ∆z = -3.0 mm Top 3C 40.7 5.7 throttles, then move back in by 0.2 mm Min coupling, shifting pencil towards back (-Z) until charging 0 ∆z = -3.2 mm Top 2.5C 48.5 4.9 throttles, then move back in by 0.2 mm Min coupling, shifting pencil towards back (-Z) until charging 0 ∆z = -3.2. mm Top 1C 38.5 5.0 throttles, then move back in by 0.2 mm Digital Ping No Pencil Side (right in 0 front of the N.A. 69.4 4.6 (No RX) (No RX) TX window) © 2018 PCTEST LAB Page 6 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results Conclusion The worst-case H-Field and E-Field measurements have been determined to be 69.4 A/m and 7.8 V/m respectively. Correlation between Measured and Simulated H-Field Numerical analysis for WPT was carried out to establish correlation between measured and simulated H-field. Following Table shows that correlation information. The Measured H-field shows good agreement with Numerical analysis. H-field Measurements BCGA1876 H-field Simulations (A/m) (A/m) Probe Optimal Optimal Distance Worst Case Worst Case Charge Probe alignment alignment from the (Min (Min Profile Position (Max (Max DUT Coupling) Coupling) (mm) coupling) coupling) 0mm 45.5 61.6 47 72 10C Top 5mm 26.3 34.3 23 36 10mm 14.7 19.6 13 21 Standalone SAR Test Exclusion Numerical analysis for WPT operation in different orientations for Max and Min coupling configurations yields SAR values which are < 0.001 mW/g @ Max charge profile of 10C. These values are well below ambient noise levels measurable in commercially available SAR systems. There is no intentional transmission taking place in object detection mode. Additionally, the overall duty cycle of ping mechanism is less than 0.1% hence this mode is not included in analysis. Based on above, per FCC Guidance, the Apple pencil charging function qualifies for standalone SAR test exclusion. © 2018 PCTEST LAB Page 7 of 8 Test Report S/N: 1C1806050010-12-R2.BCG

FCC Test Results Simultaneous SAR Test Exclusion A comprehensive numerical SAR analysis is carried out for WPT operation in conjunction with SAR hotspot analysis for WLAN/BT antennas to address compliance in simultaneous transmit conditions. The Tx coil is very small (~8.3mm) and its at least ~43mm away from the closest radiating element on its either side. The SAR gradient for the nearest radiating elements to the WPT Tx Coil is very localized and falls off substantially at the location of the WPT Tx coil (see Figure 2). SAR hotspot gradient shown in Figure 2 is without the Apple pencil attached to the iPad. With Apple pencil attached to the iPad, SAR will be lower. Even in the case of dual band operation (5GHz +BT) from a single antenna, the SAR is highly localized. Based on above, per FCC Guidance, the Apple pencil charging function qualifies for simultaneous SAR test exclusion. Figure 2 Right Edge Overlay Showing Localization of Simultaneous Peaks © 2018 PCTEST LAB Page 8 of 8 Test Report S/N: 1C1806050010-12-R2.BCG


Document Created: 2019-03-24 13:41:20
Document Modified: 2019-03-24 13:41:20
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