Rainbow Electronics 71M6542G - Manual (Page 139)

v1.1 © 2008–2011 Teridian Semiconductor Corporation 139
6.2 Recommended External Components
Table 94: Recommended External Components
Name From To Function Value Unit
C1 V3P3A GNDA Bypass capacitor for 3.3 V supply
≥0.1 ±20% µF
C2 V3P3D GNDD Bypass capacitor for 3.3 V output 0.1
±20% µF
CSYS V3P3SYS GNDD Bypass capacitor for V3P3SYS ≥1.0 ±30% µF
CVDD VDD GNDD Bypass capacitor for VDD 0.1
±20% µF
CVLCD VLCD GNDD
Bypass capacitor for VLCD pin (when
charge pump is used)
≥0.1 ±20% µF
XTAL XIN XOUT
32.768 kHz crystal – electrically similar to
ECS .327-12.5-17X, Vishay XT26T or
Suntsu
SCP6–32.768kHz TR (load
capacitance 12.5 pF).
32.768 kHz
CXS XIN GNDA
Load capacitor values for crystal depend on
crystal specifications and board parasitics.
Nominal values are based on 4 pF board
capacitance and include an allowance for
chip capacitance.
15
±10%
pF
CXL XOUT GNDA 10
±10% pF
6.3 Recommended Operating Conditions
Unless otherwise specified, all parameters listed in 6.4 Performance Specifications and 6.5 Timing
Specifications are valid over the Recommended Operating Conditions provided in Table 95 below.
Table 95: Recommended Operating Conditions
Parameter Condition Min Typ Max Unit
V3P3SYS and V3P3A Supply Voltage for
precision metering operation (MSN mode).
Voltages at VBAT and VBAT_RTC need
not be present.
VBAT=0 V to 3.8 V
VBAT_RTC =0 V to
3.8 V
3.0 3.6 V
VBAT Voltage (BRN mode). V3P3SYS is
below the 2.8 V comparator threshold.
Either V3P3SYS or VBAT_RTC must be
high enough to power the RTC module. V3P3SYS < 2.8 V
and
Max (VBAT_RTC,
V3P3SYS) > 2.0 V
2.5 3.8 V
VBAT_RTC Voltage. VBAT_RTC is not
needed to support the RTC and non-
volatile memory unless V3P3SYS < 2.0 V
V3P3SYS<2.0 V 2.0 3.8 V
Operating Temperature -40 +85 ºC
Notes:
1. GNDA and GNDD must be connected together.
2. V3P3SYS and V3P3A must be connected together.