PAH8011ES Product Datasheet
Low Power Heart Rate Monitor Optical Chip
PixArt Imaging Inc.
4.4 Design Guidelines
4.4.1 Schematic Design
1. VDDM & VDDIO & VDDLED: 3.3V, VDD18V: 1.8V (for 3.3V System)
2. VDDM & VDDLED: 3.3V~3.6V, VDDIO: 1.8V, VDD18V: 1.8V (for 1.8V System)
3. VDDM & VDDLED: 3.3V~3.6V, VDD18V: 1.8V, VDDIO: 2.8V (for 2.8V System)
4. It is recommended to separate the power system of VDDM/VDDLED and wireless system to avoid power interference.
5. The maximum load current of LDO (supplying power to VDDM/VDD18V/VDDLED/VDDIO) need to be larger than
250mA. For maximum current of each power rail, refer to IDDM_MAX, IDDLED_MAX, IDDD_MAX, IDDA_MAX,
IDDIO_MAX and IDDAY_MAX parameters in Table 5. DC Electrical Specifications
6. I2C_SDA and I2C_SCL must pull high to VDDIO with resistor.
7. VDDM, VDDD, VDDA, VDDAY must have 0.1µF capacitor connecting to GND and place closely to 8011.
8. The AGND, DGND and LEDGND must be separated and connected to PCB main GND.
9. INT1 pin is recommended to be connected to MCU HW INT as data ready INT for power saving.
10. INT2 pin is recommended to be connected to MCU HW INT for touch function.
11. Ensure that the VDDM, VDDLED, VDD18V’s power noise should be under 100mV. (with 0.1µF and 10µF capacitor)
12. At power on, VDDIO must be powered on equal to or first than VDD18V.
Note: When VDDIO must be powered on first before VDDM, host should prevent using the I2C interface (connected
with chip) to switch the LDO providing VDDM voltage.
13. At power off for 1.8V IO system, VDDM must be powered off first than VDD18V/VDDIO.
14. At power off for 2.8V/3.3V IO system, VDDIO and VDDM must be powered off first than VDD18V.
15. When PAH8011ES is not in used, put the chip into Power Down Mode.
4.4.2 Recommend Layout PCB
4.4.2.1 Pad Dimension on PCB/FPC
1. Pad size design:
. If use solder mask defined (SMD), pad size is referred as solder mask opening size.
. If use non-solder mask defined (non-SMD), pad size is referred as copper metal size.
2. Recommended dimension of pad is shown in Figure 8. The actual pad size design will need to consider components
aside. (All dimensions are in mm)
Figure 8. Recommend Layout PCB
Version 1.1 | 20 Oct 2017 | 31008AEN
PixArt Imaging Inc. http://www.pixart.com
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PIXART [ PIXART IMAGING INC. ]
