STM1404 3 V FIPS-140 security supervisor with battery switchover Features STM1404 supports FIPS-140 security level 4 Four high-impedance physical tamper inputs Over/under operating voltage detector Security alarm (SAL) on tamper detection Over/under operating temperature detector Over/under temperature thresholds are QFN16, 3 mm x 3 mm (Q) customer-selectable and factory- programmed Supervisory functions Automatic battery switchover Optional V (1.237 V) REF RST output (open drain) (Available for STM1404A only) Manual (push-button) reset input (MR) Low battery supply current (5.3 A typ) Power-fail comparator (PFI/PFO) Secure low profile 16-pin, 3 x 3 mm, QFN Vccsw (V switch output) CC package Low when switched to V CC RoHS compliance High when switched to V (BATT ON BAT Lead-free components compliant with the indicator) RoHS directive Battery low voltage detector (power-up) Table 1. Device summary Standard Physical Over/under Over/under V REF V status, Vccsw status, OUT Device supervisory tamper voltage temperature (1.237 V) during alarm during alarm (1) functions inputs alarms alarms option (2) STM1404A ON Normal mode (3) (4) STM1404B Note High-Z High (4) STM1404C Note Ground High 1. Reset output, power-fail comparator, battery low detection (SAL, RST, PFO, and BLD are open drain). 2. Normal mode: low when V is internally switched to V and high when V is internally switched to battery. OUT CC OUT 3. Contact local ST sales office for availability. 4. Pin 9 is the V pin for STM1404A. It is the V pin for STM1404B/C. REF TPU August 2008 Rev 5 1/36 www.st.com 1Contents STM1404 Contents 1 Description . 6 1.1 V pin modes . 6 OUT 1.1.1 STM1404A 6 1.1.2 STM1404B 6 1.1.3 STM1404C 6 2 Pin descriptions . 12 2.1 SAL, security alarm output (open drain) 12 2.2 TP , TP 12 1 3 2.3 TP , TP 12 2 4 2.3.1 Vccsw, V switch output . 12 CC 2.4 BLD, V low voltage detect output (open drain) 13 BAT 2.5 Active-low RST output (open drain) . 13 2.6 MR, manual reset input 13 2.7 PFO, power-fail output (open drain) . 13 2.8 PFI, power-fail input . 13 2.9 V , reference voltage output (1.237, typ) . 14 REF 2.10 V . 14 OUT 2.11 V . 14 TPU 2.12 V 14 CC 2.13 V . 14 BAT 2.14 V 14 SS 3 Operation . 15 3.1 Reset input 15 3.2 Push-button reset input 15 3.3 Backup battery switchover 15 3.4 Applications information 16 3.5 Negative-going V transients and undershoot 17 CC 4 Tamper detection . 18 4.1 Physical 18 2/36