Cinterion
®
ELS81-US Hardware Interface Description
2.1 Application Interface
53
els81-us_hid_v01.004
2017-09-27
Confidential / Preliminary
Page 17 of 107
2.1.2
Signal Properties
Table 2:
Signal properties
Function
Signal name
IO
Signal form and level
Comment
Power
supply
BATT+
BB
BATT+
RF
I
WCDMA activated:
V
I
max = 4.5V
V
I
norm = 3.8V
V
I
min = 3.0V during Transmit active.
Imax = 900mA during Tx
LTE activated:
V
I
max = 4.5V
V
I
norm = 3.8V
V
I
min = 3.0V during Transmit active.
Lines of BATT+ and GND
must be connected in
parallel for supply pur-
poses because higher
peak currents may occur.
Minimum voltage must
not fall below 3.0V includ-
ing drop, ripple, spikes
and not rise above 4.5V.
BATT+
BB
and BATT+
RF
require an ultra low ESR
capacitor:
BATT+
BB
--> 150µF
BATT+
RF
--> 150µF
If using Multilayer
Ceramic Chip Capacitors
(MLCC) please take DC-
bias into account.
Note that minimum ESR
value is advised at
<70m
Ω
.
Power
supply
GND
Ground
Application Ground
External
supply
voltage
V180
O
Normal operation:
V
O
norm = 1.80V ±3%
I
O
max = -10mA
SLEEP mode Operation:
V
O
Sleep = 1.80V ±5%
I
O
max = -10mA
CLmax = 100µF
V180 should be used to
supply level shifters at
the interfaces or to supply
external application cir-
cuits.
VCORE and V180 may
be used for the power
indication circuit.
Vcore and V180 are
sensitive against back-
powering by other sig-
nals. While switched off
these voltage domains
must have <0.2V.
If unused keep lines
open.
VCORE
O
V
O
norm = 1.2V ±2.5%
I
O
max = -10mA
CLmax = 100nF
SLEEP mode Operation:
V
O
Sleep = 0.90V...1.2V ±4%
I
O
max = -10mA
Ignition
ON
1
I
V
IH
max = 5V tolerant
V
IH
min = 1.3V
V
IL
max = 0.5V
Slew rate < 1ms
ON ___|~~~~
This signal switches the
module on, and is rising
edge sensitive triggered.
Internal pull down value
for this signal is 100k
Ω
.